Werkstoffe und Korrosion 37, (1986) Abstr. 2170-2175 R 171

International Corrosion Abstracts mit den Untergruppen

Korrosions- und Werkstoff- prufung

Arbeiten uber mehrere Werk- stoff gruppen

Eisenmetalle

Nichteisenmetalle

Corrosion and materials testing Nichtmetallische anorganische Non-metallic inorganic Werkstoffe materials Kunststoffe und andere

Metallische Uberzuge Metal coatings

Plastics and other Comprehensive papers covering organische Werkstoffe organic materials several materials groups

Ferrous metals

Non-ferrous metals

Nichtmetallische anorganische Non-metallic inorganic Uberzuge coatings Organische Uberzuge Organic coatings

Diese Rubrik enthalt Referate ausgewahlter Fortschrittsberichte und Ubersichtsartikel, die in enger Zusarnrnenarbeit unserer Redaktion rnit Metals Abstracts (The American Society for Metals and The Metals Society, London) entstehen. Leser, die die hier referierten Arbeiten in vollern Wortlaut zu erhalten wunschen werden gebeten, sich an the Institute of Metals, 1 Carlton House Terrace, London SWlY 508, England, oder an The American Society for Metals, Metals Park, OH 44073, U.S.A. (nicht jedoch an die VCH Verlagsgesellschaft mbH!) zu wenden. Die Kosten fur Fotokopien betragen $8.00 fur jeweils 10 Seiten und $3.00 furzusatzliche 10 Seiten (US-Office) oder f 5.00 fur 10 Seiten (UK-Office). Einen Schlussel zu den abgekurzten Quellenangaben bietet der ,,International Serials Catalogue, Part I: Catalogue“, der vorn International Council of Scientific Unions Abstracting Board (ICSU AB), 51, Bbd. de Montmorency, F-75016 Paris, bezogen werden kann.

This column contains abstracts of selected progress reports and review articles which arise out of our close collaboration with Metals Abstracts. Readers wishing to obtain the complete text of articles abstracted in this section are requested to approach the Institute of Metals, 1 Carlton House Terrace, London SWlY 5DB, England, or the American Society for Metals, Metals Park, OH 44073, USA. (not, however, VCH Verlagsgesellschaft rnbh!). The photocopying charges are $8.00 per ten pages and $ 3.00 per additional ten pages (U.S. office) or f 5.00 per ten (U.K. office). A key to abbreviated source lists is provided in the “International Serials Catalogue, Part I: Catalogue”, published by International Council of Scientific Unions Abstracting Board (ICSU AB), 51, Blvd. de Montmorency, F-75016 Paris.

Corrosion and materials testing/ Korrosions- und Werkstoffprufung

86-2170 Alternat ing Current Corrosion. A four year, field-oriented. AC cor- rosion investigation was conducted to verify previous conclusions indicating min. influence of 60 Hz AC on cathodically protected pipelines. The effects of AC on galvanic anodes and on metals associated with electric systems are also docu- mented and conclusions and suggestions for optimum corrosion control of under- ground facilities under AC influence are offered. 11 ref.-AA A.W. Hamlin Mafer. Perform., Jan. 1986, 25, ( l ) , 55-58. [in English]. ISSN 0094- 1492.

86-2171 Stress Corrosion C r a c k i n g and C r x k T i p Adsorp t ion : Considerat ion Regarding the Role of Alloy Dissolut ion Products. Evidence linking two crack tip processes, anodic dissolution and chemisorption. to stress corrosion cracking (SCC) is presented. The absorption mechanism as proposed by several investigators is discussed. For the SCC of Cu-Zn alloys the cracking appears incompatible with the adsorption of a specific environmental species. The cathodic discharge of dissolution products at the crack tip under electrochemical conditions is considered. The discussion indicates that the mechanism is applica- ble to a pure element. There are observations that suggest the crack tip reactions may not be deducible from the surface polarization. Hydrogen evolution at the crack tip of some Al alloys may be increased by anodic polarization. The similarity between SCC and liquid metal embrittlement (LME) in 7075 Al is discussed. A model proposed for SCC mechanism is applicable to materials which fail in a brit- tle manner and may be applicable l o hydrogen and liquid metal embrittlement. It is concluded that SCC mechanism establishes a link between SCC and LME. 50 ref -H B.C. M.B. Hintz. Scr. Metall.. Dec. 1985, 19, (12), 1445.1450, [in English]. ISSN 0036- 9748.

86-2172 Onset of Oxidat ion of Al(111) at L o w Temperatures: a Study b y E lec t ron-Energy-Loss S p e c t r o s c o p y a n d , A u g e r E l e c t r o n Spectroscopy. The early stages of oxygen adsorption and oxide formation on Al(111) have been studied at 135K using a combination of electron-energy-loss spectroscopy and Auger electron spectroscopy. Both surface and subsurface binding sites are occupied at 135K, even at an 0 exposure as low as 1.8 x I O l 5 moleculesicrn2. Further 0 exposure preferentially increases the population of subsurface sites. When a sufficient number of 0 atoms occupy surface and subsur-

face sites in close proximity, clustering occurs, resulting in AI,O, formation. Alumi- num oxide is characterized by a three-peak vibrational spectrum with a characteristic loss feature at 325-425 cm-’ and a distinct Auger transition at 54 eV. Surface spectroscopic studies of Al(111) oxidation are facilitated at low temp. where kinetic retardation permits separation of the processes of chemisorp- tion, penetration. and oxide formation. 11 ref.-AA J G . Chen. J.E. Crowell. J.T. Yates, Jr. Phys. Rev. 8, Condens. Matter. 15 Jan. 1966, 33, (2). 1436-1439, [in English]. ISSN 0163-1629.

86-2173 Corrosion of a Rotat ing Iron Disk in Laminar, Transition, and Ful ly Developed Turbulent Flow. Electrochemical corrosion generally involves the interaction of numerous phenomena. A model is presented which accounts for the different hydrodynamic regimes across the surface, ohmic potential variations, and the simultaneous occurrence of oxygen reduction and oxidation of Fe. The active-passive transition for Fe is presumed to occur at a specific value of the electrode potential. Results illustrate the importance of disk size, 0 concentration, and solution conductivity upon the corrosion rate distribution. The calculations also compare well with the experimental results of LaQue. 13 ref.-AA C G Law, Jr , J Newman J Electrochem SOC, glish] ISSN 0013-4651

Jan. 1986, 133, (11, 37-42, [in En-

86-2174 Basic Ox ida t ion Principles: G r o w t h of Continuous Scales. Protective scales separate the metal and the reacting gas. and growth rates are determined by diffusion of the reactants or by transport of electrons through the scales. This diffusional transport takes place by lattice diffusion and diffusion along high diffusivity paths (grain boundaries, dislocations). The relative impor- tance of these diffusional transport mechanisms depends upon the properties of the scales and temp. These different aspects of scale growth on Ni and Cr are dis- cussed. Different types of reaction behaviour are primarily illustrated by metal- oxygen reactions. 44 ref.-AA P. Kofstad. Surface Engineering: Surface Modification of Materials [Proc. Conf.], Les Arcs, France, 3-15 July 1983, Martinus Nijhoff Publishers, P.O. Box 163, 3300 AZ Dordrecht. The Netherlands. 1984. (MetA.. 8604-72-0128) 370-389. [in En- glish].

86-2175 The Role of Complexants in the Mechanism of Inhibition of the Local ised Corrosion of Metals b y Aromat ic Compounds. Abstracted from Ref. Zh Korroz., 1985, (81, K242 The anti-corrosion properties towards a number of metals of a series of anthranilic acid derivatives were compared using increases In pitting potentials and the ability of the metals to form complexes with these compounds as the criteria. The corrosion inhiblting action resulted from the formation of surface complexes in conditions of competition between the organic b a n d and chloride- or other aggressive anions. The anti-corrosion actlon of the li. gands depended on the electron density at the reaction centre. which was re- flected in the dependence of the potential shift on the thermodynamic stability of

R 172 Abstr. 2176-2189 Werkstoffe und Korrosion 37, (1986)

the metal-Iigand complexes. the degree of covalency of the metal-ligand bond and the hydrophobicity of the ligand Thus, the greater inhibiting effect was achieved for metals with a large electronegativity. e.g.. Cu and Fe, since these were capable of forming supplementary covalent bonds with the inhibitor.-A.D.M E.E Kriss ef a/ Koordinats Khim., 1985. 11, (4), 482-466, [in Russian].

86-2176 Corrosion of Underground Insulated Pipelines. The capabilities of insulating systems are said to be vastly different from those of normal under. ground pipe coatings. The insulation systems must be designed not only to con- serve energy but also to protect the pipe from aggravated corrosion that may be much more severe than experienced by non-insulated underground steel pipe. Problems associated with insulated equipment, corrosion encountered on insu- lated underground pipelines, coating systems now in use, and, finally. recommen- dations for future insulated underground pipeline applications are discussed. 23 ref.-AA J.F. Delahunt J. Prot. Coatings Linings. Jan. 1986, 3. ( 1 ) . 36-43. [in English]. ISSN 8755-1985

86-2177 Wear of Materials During Fretting Corrosion Due to Vibrational Contact Interaction. A newly developed test stand IS described which makes it possible to conduct fretting-corrosion tests under controlled vi- brational and contact loading conditions. Test results are presented for normalized steel 45 and M3 Cu. and three distinct regions of vibrational contact interaction are identified in the range 20-95 Hz (below, at, and above the resonance frequen- cy). It is shown that the wear and damage of the friction surfaces is lowest under resonance loading conditions. 8 ref.-V.L. N.L. Golego. M.N. Rozhkov, V.P. Onoprineko, A.S. Nakvakin, N.V. Kozii. Fiz. Khfm. Mekh. Mater., 1985, (3), 71-75. [ in Russian]. ISSN 04306252.

86-2178 Fractography in Fatigue at High Temperature in Pure Water Environment. Fractography is a very useful method to examine the fracture his- tory of a failed element But in many cases the fracture surface has been scaled or corroded in the working environment before analysis. Therefore, the fracture surface must often be cleaned before observation. A fracture surface which had been scaled during low cycle fatigue testing at 288°C in pure water was examined. In order to strip off the surface scales, the following five methods were employed: (1) ultrasonic vibration in 3% HCI solution; (2) ultrasonic vibration in 5% diam- monium hydrogen citrate solution; (3) ultrasonic vibration in 5% NaOH solution, (4) ion sputtering; and (5) the blank replica method. There was no trace of scale strip- ping by the NaOH solution, ion sputtering or the blank replica method, but scale was stripped off by HCI solution and diammonium hydrogen citrate solution. The vi- bration in 3% HCI solution seemed to restore the original fracture surface. The cor- rosion fatigue fracture usually started at the surface pitting corrosion. Therefore, it was very important to investigate the growth behavior of pitting corrosion for the study of the corrosion fatigue mechanism. So. the feature, size and number of cor- rosion pits on the surface of fatigue specimens at high temperature in pure water were investigated. The total number of corrosion pits examined were about 1000 It was observed that the pitting figure was complicated at the initial stage, but it changed to circular as it grew. The pitting size distribution at the occurrence Of fracture was expressible by an exponent function It was concluded that the proba- bility density function of pitting size distribution was strongly affected by the test- ing strain rate 9 ref -AA Y. Ino, Y. Arihara. J. SOC. Mater. Sci., Jpn., Sept. 1985, 34, (384). 1012-1018,'[in Japanese]. ISSN 0514-5163.

86-2179 Fatigue and Corrosion Behavior of Structures. Factors that af- fect fatigue and corrosion behavior of welded structures and describe the applica- tion of fuzzy sets to the treatment of uncertainties associated with such behaviors are discussed. Weldment factors such as joint details and residual stresses are reviewed and environmental factors, including the randomness of the loading se- quence and loading rate are considered. Design rules which incorporate the ef- fects of weldment and environmental factors are noted, and uncertainties which must be considered relative to the fatigue phenomenon are highlighted. These in- clude quality control, load history, and effects of residual stresses. Corrosion fac- tors, all of which are a function of time, are explored, and the interaction of corrosion and fatigue are analyzed. Finally, the fuzzy set theory is discussed as a way of systematically considering uncertainties of the fatigue strength of a welded steel in a corrosive environment.-NTIS A.J. Hinkle, J.T.P Yao, Purdue University. PB85-234987/WMS. 1984, Pp 29, [in English]

86-2180 The Evaluation of Wire Ropes by Acoustic Emission Techniques. The main findings of this investigation reveal tha it is possible to de- tect and discriminate the failure of constituent. wires from background noise sources under both rising load and fatigue conditions. Near one-to-one correla- tions exist between wire breaks and events occupying given amplitude ranges. Linear source location techniques have allowed wire breakage to be located with a good degree of accuracy over a distance of 1.1 m under rising load conditions. Experiments to determine the attenuation of the signals resulting from wire break.' age under rising load conditions have resulted in the detection of wire over a dis- tance of 29.5 m. The amplitude of wire breaks at given distances along a rope can be calculated once the attenuation contrast for a given rope has been determined by experiment, 2 ref.-AA N F. Casey, J.L. Taylor. Er. J. Non-Destr Test.. Nov. 1985. 27, (6), 351-356. [in En- glish] ISSN 0007-1 137.

86-2181 The Embedded Disk Pressure Test (DPT): a Sensitive Technique to Investigate Materials Embrittlement. A disk clamped at the edges can be ruptured by gas pressure. The test is sensitive to plastification and embrittlement by interstitials e.g. hydrogen. By composing test results with service Performance a quality criterion has been established.-D P. R . Arnould-Laurent, J.P. Fidelle. Bull. Cercle Etud. Mgtaux, Mar. 1981, 14, (13). 8 1-8.9, [in English and French]. ISSN 0366-4104

86-2182 Electrical Potential Difference Method in Studies of the Kinetics of Crack Growth. Calibration curves were obtained correlating electri- cal potential difference ratios uI2/u3., as a function f(1) of growing fatigue-crack length for different positions of placement of electrical potential contacts on flat 50 x 8 mm steel 15Kh2NMFA specimens, each having a lateral notch. The curves are useful for kinetics studies where test specimen geometry and the p o w

tioning of the condenser energy-storage welded potential contact 1 and screw- clamped potential contacts 2, 3, and 4 are similar to those employed in producing the curves and regression equations. 3 ref -L.S D. V M Timonin, M V Yaroshenko, 0 A Chernyavskii Zavod Lab, 1985, (10). 70 72 [in Russian] ISSN 032 t 4265

86-2183 Non-Destructive Control of Corrosion in Aluminum Alloy Assemblies. Corrosion is a frequent occurrence in damage in Al assemblies, so that it is necessary t o have a non-destructive control method to detect it before its' effects become too severe (repair costs). as might be the case if one is limited to visual inspections. Different control methods were evaluated to detect the first stages of corrosion (intergranular corrosion): ultrasound, radiography. neutrono- graphy, Foucault currents, FBT and UFD-S. Interesting results have been obtained by two methods, neutronography and ultrasound, using signal treatment techniques.-NTIS D. Lecuru. Societe Nationale lndustrielle Aerospatiale. PB85-204923/ WMS. 2 1 Jan. 1985. Pp 65, [in French]

86-2184 Erosion by Solid-Particle Impacts: a Testing Update. A work- shop on erosion by solid particles focused attention on the status of applicable testing technologies ASTM Standard G 76-83, in which erodent particles are en- trained in gas jets, was reviewed, and procedural variations based on i t were de- scribed and discussed. Among the factors considered were cratering. particle fluxes, particle feeding, and the characteristics of nozzles, specimen surfaces. and erodent particles. Many effects of the foregoing factors are not yet fully under- stood Jet-type erosion tests such as ASTM G 76 cannot simulate all practicai cir- cumstances in which erosion by solid particles occurs. Therefore the development of additional standardized testing procedures is needed Two alternatives, slinger- type testing and wind-tunnel testing, with potential for further development were described. 7 ref -AA F W. Wood ASTMJ. Test. €Val, Jan 1986, 14, ( l ) , 23-27, [in English]. ISSN 0090- 3973

86-2185 lntergranular Corrosion Testing of Nickel-Ease Alloys. An electrochemical test method based on the electrochemical potentiokinetic reacti- vation (EPR) test has been employed to quantify the degree of sensitization in sev- eral austenitic Ni-base alloys (Inconel 600, Sanicro 31H. Inconel X-750). In addition to the electrochemical test several standardized test methods have been used and the results of the tests are compared. The results indicate that the elec- trochemical reactivation test is a useful tool for comparing the degree of sensitiza- tion between various sensitized conditions. However, the determination of an exact quantitative value is difficult because of many variables affecting the numeri- cal result of the EPR test. 26 ref.-AA T Kekkonen. P. Aaltonen. H Hanninen. Scand J. Metal l , 1985. 14, (5), 243-251, [in English] ISSN 0371-0459

86-2186 Radiographic In-Service Inspection of Cast Austenitic Nuclear Plant COmpOnentS. The sensitivity of in-service radiography for the detection of circumferential fatigue cracks in large cast austenitic stainless steel piping such as that used in pressurized-water reactor nuclear generating units is defined. It is suggested that thermal fatigue cracks > 20-25% through-wall dimension can be detected using equipment now in use for related inspections in nuclear plants. The experimental and analytical bases for this determination are provided, as are brief descriptions of Minac technology. crack morphology, and related subjects It should be noted that few, if any. service-related flawshave ever been found in cast austenitics in light-water reactor service Hence, inspection of any form must be viewed in the context of appropriate flaw evaluation procedures rather than in iso- lation. The appropriate evaluation background, including assessment of allowable flaw dimensions, influence of fabrication practice, and other considerations IS illus- trated. Finally, an assessment of "filmless" radiography as a means ot reducing in- spection costs is noted. 8 ref.-AA M.E. Lapides Mater. Eva/., Jan. 1986, 44, (1). 108-1 13, [in English]. ISSN 0025- 5327.

86-2187 Corrosion Tests. If manufacturers are to guarantee corrosion resis- tance, as is increasingly being demanded, they are required to undertake acceler- ated life tests to check their designs. German standards already exist for such tests, the most important being DIN 50 021, 50 907 for salt spray testing and DIN 50017 218 for humidity testing A changing combination of both types of tests Often produces the best results Such tests can be carried out with a variable cor- rosion test chamber (KWT) which can automatically regulate the desired test pattern.-T.S.H. B:J. Schniewind. Oberflache JOT, Dec. 1985, 25. (12). 28-30. [in German]. ISSN

86-2188 Service Properties of Complex Esters Used as Additives to a Mineral Oil. Abstracted from Ref. Zh. Korroz.. 1985, (10). K311 Physico- chemical and electrochemical methods were used to study the service properties in relation to the behaviour of metals of complex esters based on saturated and unsaturated dicarboxylic acids added to mineral oils. These additives. at e.g.. the 5% level in the [USSR] oil M-6. had advantages over dioctylsebacate and penta- erythritol esters of C5-Cg acids in terms of lubrication. corrosion protection and prevention of fretting corrosion.-A.D.M. I.Yu. Rebrov. S.B. Borshchevskii, M.V. Kuznetsov, N.P. Glukhoedov Khim Tekh- no/ Top/. Masal, 1985, 13). 22-24, [in Russian].

86-2189 Hydrogen Permeation in Optical-Fiber Submarine Cable Systems. Currently, there are seven international submarine coaxial cable sys- tems in Japan The capacity will have to b e increased substantially to meet the fu- ture needs. Because of the various disadvantages of the coaxial cable system, the optical-fiber system is considered an ideal substitute for it. Fundamental com- ponents of the optical-fiber cable systems, and the structu;es and the materials of the cable and connectors are summerized. The recent finding of increase in trans- mission loss in optical-fibers due to hydrogen generated by reactions between metals and sea water permeated in optical-fiber submarine cables was confirmed by a simulated experiment. In addition. the amount of H generated by electrochem- ical reaction between metals and sea water was measured. Aluminum, Cu and Fe were put into glass containers filled with sea water under four conditions-single metal, two separated metals, two attached metals. and two attached metals with electric current. The gases generated were analyzed. It was concluded that the

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Werkstoffe und Korrosion 37, (1986) Abstr. 2190-2207 R 173

amount of H generated depends on the conditions of metallic materials and the ex- istence of e!ectric current. Possible causes for H permeation into the cables are given. The use of metallic materials, which generate little H when reacted with sea water, was suggested. 7 ref -S.C M. Kuwazuru. Bosei Kanri (Rust Prev. Control), July 1985. 29, (7). 203-209. [in Jap- anese] ISSN 0520-6340.

86-2190 The Effects of Applying Electrolytic Protection on Sedimentation Tanks of Waste Water Treatment. The corrosion in sedimen- tation tanks and the effectiveness of electrolytic protection were studied. Three sedimentation tanks actually used in Japan were investigated. The descriptions of these tanks, the corrosion conditions before applying electrolytic protections, and the causes of corrosions are given. Several materials, which can be used for an- odic protection, were applied to the tanks and the effect was examined. It is con- cluded that anodic protection is an effective method for corrosion control in all cases. 4 ref.-S.C. M. Abe. K. Abe. Bosei Kanri (Rust Prev. Control), July 1985. 29, (7). 210-218. [in Japanese] ISSN 0520-6340.

86-2191 The Kinetics of Equilibrium Oxidation of the Surface of Metals and Non-Stoichiometric Oxides with Continuous Laser Heating. Abstracted from Re/. Zh. Korroz., 1985. (8), K32. Studies were made of the kinet- ics of oxidation of metal surfaces with a temp. gradient in the oxide film produced by laser irradiation and of the distribution of defects through the oxide thickness. In isothermal oxidation if the defects existed in certain charge conditions then the distribution was non-linear. In the presence of a temp. gradient the rate of oxida- tion was, depending on the conditions. greater or less than the isothermal fate with the oxidation law departing from parabolic.-A.D.M. D.T. Alimov. Yu.1. Mitin, V.K. Tyugai, P.K. Khabibullaev. Poverkhn.. Fiz., Khim., Mekh , 1985. (4). 126-133. [in Russian].

86-2192 The Selection of Inhibitors of Hydrogen Sulphide Corrosion. Abstracted from Ref. Zh. Korroz., 1985. (€31, K259 Tests were conducted to select corrosion inhibitors for use in benzole plants with a view to replacing the imported [into Russia] NALKO 165-AS. The USSR inhibitors VNKh-101 and VNKh-207 [anal- ysis not known] gave 98.99% protection at a concentration of 100 m g / l in cooling and condensing components in benzene production.-A.D.M. M.A. Geidarov. A.G. Guseinov, T.P. Kuznetsova. Azerb. Khim. Zh., 1984, (5). 107- 109, [in Russianl.

86-2193 Apparatus for Studying Corrosion Processes in the Use of Carbon Dioxide for Enhanced Oil Recovery. Abstracted from Ref. Zh. Korroz., 1985, (9). K666. Equipment was developed in which conditions could sim- ulate the C02 corrosion of structural steels as in secondary recovery processes. Electrochemical and gravimetric methods could be used for studying the effects of inhibitors and protective coatings in C02-saturated media.-.A.D.M. A.R. Marin. A.F. Nizamova. A.V. Gil'mutdinov. Sb. Nauchn. Tr. Bashk. Nauchno- lssled. Proekt. lnst. Neft. Prom-sf., 1984. (68). 67-70. [in Russian].

86-2194 Cathodic Protection Using Sacrificial Anodes of Deep Submersible Pumps. Abstracted from Ref. Zh. Korroz., 1985. (9). K292. Studies were made of the protection of steel. and in particular submersible pumps, in the corrosive waters of artesian wells. Use was made of anodes of the Mg alloy Mg- 95pch to establish a potential of -1600 mV (Cu/CuSO,). To provide uniformly distributed protection three anodes were mounted along the length of the pump by means of insulated bolts.-A.D.M. V.S Smirnov. Neft. Gaz. Prom-st. (Kiev), 1965. (2). 46-47, [in Russian].

86-2195 Choosing an Accelerated Corrosion Test. Numerous acceler- ated corrosion tests are available to match various "real life" conditions. Corro- sion mechanisms are explained, outlining four types. Eleven tests are described and applications tabled for 30 coating/substrate combinations.-J.V.R. F. Altmayer. Met. Finish., Oct. 1985. 83. (10). 57-60, [in English]. ISSN 0026-0576

86-2196 Cathodic Protection of Interconnected Pipe Systems in the Town Area. Experiences acquired by a number of large gas distribution organisa- tions with cathodic protection of interconnected pipe systems in urban areas are described. The types and location of failures are discussed, with examples and costs of cathodic protection installations on new and old distribution systems. Ca- thodic protection can be successfully applied to welded, bitumen-coated pipe grids in large cities 7 ref -H.S. P Pickelmann. 3Rlnt.. Aug. 1985. 24, (8). 424.428, [in German]. ISSN 0340-3386.

86-2197 Cathodic Protection of Pipelines and Tanks at an Aircraft Refuelling Station. A cathodic protection system with three separate protective ranges installed on a 31 km long refuelling pipeline at Frankfurt Airport is de- scribed, Explosion prevention requirements had to be met. Measurements showed that cathodic protective potentials were available at all points, without adversely affecting adjoinrng plant. No corrosion damage has occurred after three years Of operation.-H S. K..D. Appel. N. Liedtke. 3R hf. , Aug. 1985, 24. (8). 431-433, [in German]. ISSN 0340-3386

86-2198 Extracts from Coal as Inhibitors of Corrosion [of Metals] in Acid Media. Abstracted from Ref Zh. Korroz.. 1985. (9). K238. The mass-loss method was used to study the protective properties of extracts from brown coal and gas coal as corrosion inhibitors for addition l o inhibitors of the [USSR] ChM class. Using gas coal it was possible to improve protection in 10% HCI at 25°C from - 65 l o - 87% and at 70 and 90°C from - 52 and 44 to - 96 and - 89%. resp. Protection was also improved in 10% H2S04 particularly at elevated temp. The amount of hydrogen uptake was also reduced compared with that obtained with the ChM class. The chemical nature of the constituents responsible for the im- provements is described.-A.D.M. G.V. Samoilenko eta/. Khim. Tekhnol (Kiev), 1985. (2), 6-8, [in Russian].

86-2199 Corrosion Protection of Equipment and Pipework of Catalytic Reformers. Abstracted from Ref. Zh. Korroz.. 1985, (8). K260. Corrosion inhibi- tors were studied for the protection of catalytic reformers from low temp. acid con- densate corrosion. Treatment with 0.1% aqueous solution of the inhibitor KLOE-I5

[analysis not known] with 2% of a base such as NaOH or monoethanolamine was developed. The inhibitor was used in a preliminary washing stage and then during the regeneration process.-A.D.M. G.A. Andreeva. V.V. Burlov. O.N. Prasolova. Khim Tekhnol. Top/ Masel, 1985, (4). 6-7, [in Russian].

86-2200 Method and Composition for Inhibiting Corrosion. Compositions useful as corrosion inhibitors for high density brines at high temper- atures comprise phosphonium salts, such as triphenyldocosyl phosphonium chlo- ride. M. Coffey. M Y Kelly, W.C. Kennedy, Dow Chemical. 2 May 1985, [in English] Pa- tent no EP0139567 (EUR). 21 Sept. 1984.

86-2201 Electrical Corrosion Protection for a Vehicle. An apparatus for cathodic corrosion protection in a vehicle is disclosed in which an insulated earth contact is attached to the vehicle and connected to the positive pole of a potential source; the negative pole is connected to the vehicle, a potential indicating device being sometimes provided. R. Padinger 5 June 1985. [in German]. Patent no. EP0143772 (EUR). 22 Oct. 1984

86-2202 Development of an Expert System for Design Consultation on Marine Corrosion. An account is given of the experience gained in collecting and structuring corrosion knowledge for a computer-based expert system able to give design consultation on the corrosion aspects of marine installations. As an aid to building the system, the character of corrosion knowledge and the behaviour of a human consultant were analyzed. The importance of providing a dialogue that is friendly to the user is emphasized. Systematic listings are given of the various fac- tors that need to be defined by the questions and responses of the dialogue, in order to specify a corrosion situation completely. The suitability of various types of literature source is considered: the means adopted for summarizing and storing the resulting knowledge, and for presenting it to the user, are described. Aspects of the system requiring further development are identified and possible solutions are outlined. 4 ref.-AA J.N. Wanklyn. N.J.M. Wilkins. Br. Corros. J., 1985, 20, (4). 161-166. [in English]. ISSN 0007-0599.

86-2203 Anticorrosion Protection in the Polish Chemical Industry. Based on an enquiry, the current state of corrosion and anticorrosion protection in the Polish chemical industry is presented. Anticorrosion services in these works, main technical problems solved or solved in co-operation with research develop- ment centres, recording of corrosion losses, usage of Polish and foreign anticorro- sion materials and some technical problems to be solved in the future. are all discussed.- AA E Smieszek. Ochr PrzedKoroz.. Feb 1985. 28. (2). 33-35. [in Polish]. ISSN 0473- 7733.

86-2204 Inhibitory Anticorrosion Protection in the Chemical Industry. Current State and Possibilities in Poland. The operation mechanism of inhibi- tors, taking into account their chemical composition and dividing them into oxidiz- ing. adsorptive and membrane inhibitors. is reviewed. Inhibitors used in the refinery and the petrochemical industry and those designed for industrial water systems are described in detail. Inhibitors produced in Poland and other COMECON coun- tries are also presented. with their application range and possible applications in the future. Usage of inhibitors ensures a relatively simple method of anticorrosion protection and each zloty, spent for this purpose, results in seven to ten zlots of economic effect.-AA J. Mieluch, A Szyprowski. J. Jurek. Ochr. PrzedKoroz., Feb. 1985, 28, (2). 35-41, [in Polish] ISSN 0473-7733.

86-2205 Corrosion Problems and Anticorrosion Protection in the Silesian Refinery Works. The basic causes of installation. equipment and me- tallic structure corrosion in a kerosene refinery are presented, classifying them in the following groups: atmospheric. water, under-insulation corrosion and corrosion under the influence of chemical substances. Many examples are given of a possi- bility to reduce considerably the costs of anticorrosion protection by using apF)ro- priate high quality anticorrosive materials Also discussed are difficulties arising in anticorrosion works when the refinery operates. which is a reason for taking greater care in primary protection and proper designing of the equipment (anticor. rosion allowance) which considerably increases the equipment life.-AA K. Profus, R. Myrczek. Ochr PrzedKoroz.. Feb. 1985, 28. (2). 41-43. [in Polish]. ISSN 0473-7733.

86-2206 Newer Coolants Developed for Modern Automobile Engines. A short history of the development of engine coolants by the BASF organization in FRG, which culminated in their patent for "Glysantin anti-corrosion" agent, is given. Anti-corrosive functions of modern engine coolants are examined. Six types of cor- rosion found in engines are listed. erosive corrosion. galvanic corrosion, pitting, cracking, cavitation and hot water corrosion Some new tests devised for coolant-antifreeze are mentioned, i e. knock chamber test, water pump test, hot surface corrosion test and hot finger test.-R.N.B. Tech. Uberwachung, Sept. 1985, (9), 316-318. [in German]. ISSN 0376-1 185.

86-2207 Corrosion Resistant Materials Handbook. Fourth Edition. (Book). The fourth edition of the Handbook has been completely revised and vastly expanded, based on the latest available technical data. This volume will provide use101 information which will enable the concerned engineer ot manager to cut losses due to corrosion by choosing suitable commercially available corrosion resistant materials for a particular application. The > 160 detailed tables in the book are arranged by types of corrosion resistant materials. The "Corrosive Mate- rial Index" is organized by corrosive chemicals and other corrosive substances. A separate "Trade Name Index" and a '"Company Name and Address Listing" are also included. The various sections in the book cover selected categories of cor- rosion resistant materials, such as synthetic resins and polymers: rubbers and elastomers; cements, mortars. and asphalt; ferrous alloys; nonferrous metals and alloys, and glass, ceramics. and carbon-graphite A separate section presents a group of 13 tables which compare the anticorrosive merits of a cross section of commercial engineering and construction materials essential to industry The ta- bles in the book represent selections taken directly from manufacturers' literature. - AA

R 174 Abstr. 2208-2222 Werkstoffe und Korrosion 37, (1986)

D J. De Renzo. Noyes Publications, Mill Rd. at Grand Ave.. Park Ridge, New Jersey 07656, USA, 1985. (h4et.A.. 6604-72-01 16) Pp 965. [in English].

86-2208 Surface Treatment for Corrosion Protection. The first part of this survey outlines the principles of aqueous corrosion, and mentions the most im- portant methods for studying these processes. In the second part, the procedures for corrosion protection are compared. The more "classical" techniques are de- scribed together with surface alloying by physical vapour deposition (PVD) and di- rected energy processes. Examples for the use of non-equilibrium surface alloying in corrosion studies and corrosion protection are presented. 26 ref.-AA G.K. Wolf. Surface Engineering: Surface Modification of Materials [Proc. Conf 1, Les Arcs, France, 3-15 July 1983, Martinus Nijhoff Publishers, P.O. Box 163, 3300 AZ Dordrecht, The Netherlands, 1984. (Met.A., 8604-72-0128) 628-655. [in En- glish]

86-2209 Detection of Steam Generator Tube Leaks in Pressurizea Water Reactors. The early detection of small steam generator tube leaks in pressurized water reactors is discussed, including the third, and final, year's work on an NRC-funded project examining diagnostic instrumentation in water reactors. The first two years were broad in coverage, concentrating on anticipatory mea- surements for detection of potential problems in both pressurized- and boiling- water reactors, with recommendations for areas of further study. One of these areas, the early detection of small steam tube leaks in pressurized water reactors (PWRs). tormed the basis of study for the last year of the project. Four tasks are addressed in this study of the detection of steam tube leaks: determination of which physical parameters indicate the onset of steam generator tube leaks; es- tablishing performance goals for diagnostic instruments which could be used for early detection of steam generator tube leaks; defining the diagnostic instrumenta- tion and their location. and assessing the need for diagnostic data processing and display. Parameters are identified, performance goals established, and sensor types and locations are specified. 7 ref.-AA W.H. Roach. 12th Water Reactor Safety Research Information Meeting [Proc. C0nf.J. Gaithersburg. Maryland, USA. 22-26 Oct. 1984, Nucl. Eng. Des:. Nov. (1) 1985, 89, (1). 81-89, [in English]. ISSN 0029-5493

86-2210 Fracture Mechanics Evaluation of Irradiation Embrittlement in Reactor Vessel Steels Based on the Rate Process Concept. A new evalua- tion procedure for the critical fracture toughness (Kit, Kid) from Charpy-V impact absorbed energy is presented. The strain-ratel temp. effect on the cleavage- controlled fracture toughness transition is first explained by applying the concept of a stress-dependent rate process for fracture initiation. The expression de- scribed in terms of the Charpy-V energy ratio, Cv.uslCv, for fracture toughness under a constant strain rate is newly derived The feasibility of the new procedure for evaluating the irradiation embrittlement of reactor pressure vessel steel. such as SA533B-1, is here verified utilizing the data for both unirradiated and irradiated materials in the literature. Another method for the determination of coefficients in the new expression from the C;fitting curve is also presented. 31 ref.-AA F. Nogata, H. Takahashi ASTM J. Test. Eva/., Jan. 1986, 14. (1). 40-48, [in En- glish] ISSN 0090-3973

86-2211 Electrochemical Impedance Spectroscopy of Protective coatings. Electrochemical impedance spectroscopy (EIS) carried out over a wide frequency range ( l o5 to Hz) allows us to obtain mechanistic information concerning corrosion protection by coatings. Examples are given for polymer coat- ings on an Al alloy as a function of metals, information concerning the coating's properties and its changes with exposure time can be obtained from the high and medium frequency regions of the impedance spectrum. while the corrosion reac- tion at the metallcoating interface can be evaluated from the low frequency part. The pore resistance of the coating and its changes with exposure time have been used to rank different pretreatment procedures for a given metallcoating combina- tion. For Al alloys, pronounced differences in corrosion resistance between a con- version coating and an anodized layer under a polyurethane coating have been observed. The use of a segmented electrode allows measurements of the imped- ance acros's as well as under a coating. From these data, information concerning delamination can be obtained. An example is given for an epoxy coating on steel. The use of EIS as a quality control and corrosion test for anodized Al alloys is dis- cussed. The effects of the anodization procedure (sulfuric acid and chromic acid). sealing procedure (hot water and dichromate) and alloy chemistry (A1 2024, 6061 and 7075) have been studied during exposure to aerated 0.5N NaCI. Al l these pa- rameters play an important role in the corrosion resistance of the alloys. The seal- ing process can be evaluated from the high frequency pr r t of the spectrum. Pro- nounced differences in the spectra for the two sealing procedures are observed. The corrosion behavior is reflected in the low frequency part. which is essentially dominated by barrier layer properties. 23 ref.-AA F. Mansfeld. M.W. Kendig. Werkst. Korros.. NOV. 1985. 36, (1 1). 473-483, [in En- glish]. ISSN 0043-2822.

86-2212 Corrosion-Inhibition System Passes Severest Test at Chevron's Princess MEA Plant. Corrosion at Chevron's Princess plant was high. Many changes were implemented or contemplated to combat it but were ei- ther not successful or not economical. Application of Union Carbide's Amine Guard ST has successfully cut corrosion rates in both liquid and vapor spaces. 20 ref. -AA H.A. Wong, R Kohler, A.J. Kosseim, D.J. Kubek. J.G. McCullough. Oil Gas J., 11 Nov. 1985, 83, (45). 100-102. 104, 106-108. [in English]. ISSN 0030-1368.

86-2213 Corrosion Failure Analysis of a Urea-Synthesis Reactor. After five years running, a sudden failure happened to the French-made urea-synthesis reactor at Guangzhou Petrochemical Works, caused by a corrosion leak in the re- actor's lower end. Investigation shows it was due to manual unqualified welding of stainless steel overlays and the development of serious crevice corrosion.-AA C Yang. Huagong Jixie (Chem. Eng. Mach.). 1985. 12. (5). 36-41. [in Chinese].

86-2214 Corrosion Failure Analysis of High-pressure Ammonium Carbamate Condenser. A corroded sample of high pressure ammonium carba- mate condenser tubes in a urea plant is analysed by energy spectrum. scanning electron microscope and metallographic examination. The result shows that the corrosion failure resulted from poor quality in manufacture rather than from unrea- sonable process or structure of equipment. The mechanism of corrosion for this tube is described. and the corrosion form defined as intergranular general uniform

corrosion which occurs in the condition of urea production is also discussed. 10 ref. - AA T. Li, S. Xiao. Huagong Jixie (Chem. Eng. Mach.), 1985, 12. (5), 42-47, [in Chi- nese].

86-2215 The Inhibiting Action of Nitrogen-Containlng Corrosion Inhibitors in Greases. Abstracted from Ref. Zb. Korroz., 1985, (9). K277. Chronopotentiometry was used in a study of the protective properties and elec- trode potential of steel coated with inhibited greases. Benzotriazole derivatives retarded the anodic, and benzimidazole. benzoxazole and aniline derivatives the cathodic process.- A.D.M. V.G. Mel'nikov. L.B. Kapustina. L.A. Zinov'eva. Yu.V. Lun'kov. Sb. Naucbn. Tr. Vses. Nauchno-lssled. lnst. Peferab. Nefti, 1985, (461, 56-59, [in Russian].

86-2216 Functional Properties of Some Molybdenum-Containing Dithiophosphates. Abstracted from Ref. Zh. Korroz.. 1985. (9). K275. A number of oil-soluble Mo-containing derivatives of dithiophosphoric acids were prepared and examined as corrosion inhibitors. These were based on di(2- ethylhexy1)dithiophosphoric and diaryldithiophosphoric acids. All the derivatives had similar corrosion effects in relation to Pb and acted as high temp. antioxi- dants. With the disryl compounds there was an improvement in antiwear properties compared with derivatives of aliphatic alcohols. The wear of Cu in presence of these oils was however greater than with derivatives synthesised from alkylp- henols. Mo-containing derivatives are recommended for use in oils with those based on industrial alkylphenols having C,-C, alkyl radicals being the most effective.-A.D.M. E.A. Ivanova, M.F. Brailovskii. G.F. Bogdanova, G.A. Trofimov. Nefteperersb. Ne- ftekbim. (Moskov). 1984, (1 I ) , 11-13. [in Russian].

86-2217 Certain Methodological Aspects of Determining the Resistance of Structural Materials to Static Stress Corrosion Cracking. Studies of subcritical crack growth in structural materials subjected to static load- ing in a corrosive medium often rely on diagrams of static stress corrosion crack growth relating the crack growth rate to the stress intensity factor. Here, the 101- lowing two methodological problems associated with this approach are examined: consideration of electrochemical conditions at the tip of a propagating crack dur- ing testing and determination of the stress intensity factor with allowance for the actual geometry of the stress corrosion crack. Analytical expressions are ob- tained which provide an adequate description of experimental data obtained for 40KhN steel. 45 ref.-V.L. V.V Panasyuk, I.N. Dmytrakh, R.S Grabovskii. FIZ. Khfm Mekh Maler , 1985, (3). 21.28, [in Russian]. ISSN 0430-6252.

86-2218 Novel Corrosion Inhibitors. The composite zinc-containing pig- ment composed of an electrically conducting nucleus of di-iron phosphide, inter- mediate Zn-diffusion interface coating and fine particles of zinc metal surrounding the nucleus is described. Some corrosion performances as well as the zinc con- sumption in accelerated tests as the function of total initial zinc amount are given. 7 ref.-AA Z. Kalewicz. J. Oil Colour Cbem. Assoc.. Dec 1985, 68. (12). 299, 300, 303-305. [in English]. ISSN 0030-1337.

86-2219 Electrochemical Accelerated Testing of the Pitting Corrosion Resistance of High Alloyed Steel. To test the pitting resistance of high-alloy steels, a galvanostatic and a potentiodynamic test method as well as two test so- lutions of different aggressivity are described on which a future CMEA recommen- dation shall be based. Their applicability to steel grades having a higher resistance than X7Cr13 and the influence of indivtdual test parameters are dis- cussed. The advantages of the galvanostatic over the potentiodynamic method are pointed out. 7 ref.-AA I. Garz, J. Galher. E. Boese, G Riedel. Korrosion. 1985. 16. (6). 283-294. [in Ger- man]. ISSN 0023-4133.

86-2220 The Design of an Experiment to Test the Corrosion Behaviour of FeNi Alloys Under Attack From Sulfuric Acid in the Presence of H2S. For the corrosion behaviour of FeNi alloys in H2S04 solutions containing H2S, mathematical models of the relation iCD,, = f(cNI. pH. cHZs) are developed for spe- cific concentration ranges. The agreement of the calculated with the experimental data is checked. The comparison of the regression coefficients obtained for the models (quantity. amount) reveals that ieorr rises with cHZs (for all Ni contents) and decreases with cN, (up to 50%) and with rising pH value. 3 ref.-AA M. Aroyo. S. Arpadjan. R. Raicheff. Korrosion, 1965, 16, (6). 295.301. [in German]. ISSN 0023-4133

86-2221 Anticorrosion Protection in the Chemical Industry. Authors. representing Polish specialist enterprises for anticorrosion protection and thermal insulation. have discussed problems connected with the workmanship of anticorro- sion plant for the chemical industry. These problems were analysed taking into ac- count quality and supply of anticorrosion materials and equipment for surface cleaning, workmanship conditions in operating chemical works and Polish rules concerning economic calculations of work carried out. Conclusions, concerning the production of appropriate materiais and equipment and changes in the calcula- tion in order to improve the quality of protective coatings, are presented --AA A. Grzelak, Z. Szymkowiak. M. Zagrodzinski. Ochr. Przed Koroz., Feb. 1985, (21, 53-54. [in Polish]. ISSN 0473-7733.

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86-2222 Corrosion Properties of Welded CuNiFe/Steel Compounds. 1. Short Time and ASTM-Seawater Loop Tests. Short time corrosion tests and ASTM-seawater loop tests at 90°C were performed on CuNilOFe roll-clad steel compound joint weldings and on surface, spot and repair weldings in order to ex- amine the effect of iron pickup from the base metal (C-steel) or from base layers. In comparison CuNi 10-sheets with different Fe-contents and TIG-weldings on these sheets were tested. In ASTM-seawater, the corrosion resistance of weld- ings is not altered for iron dilutions with integral values between 1.5 and 5% Iron concentrations lower than 1.5% result in a reduction of the corrosion resistance. Selective corrosion at the heat affected zone was not observed. The second part of this investigation deals with the corrosion properties in seawater. 16 ref.-AA M.6. Rockel, G. Rudolph. Werkst. Korros.. Aug. 1985. 36, (8). 348.357, [in Ger- man]. ISSN 0043-2622.