The corrosive wear performance of 304 stainless steel in sulfuric acid was determined in 1N H_2SO_4 at different polarization potentials by means of a pin-disc device. The linear relationship, with different slopes between corrosive wear and loads was confirmed. It is suggested that the removal of material in cathodic polarization region only results from mechanical wear, therefore linear relationship exists with a small sloper the synergy of corrosion and wear accelerates the removal of material in over-passive region, in which high linear slope appears; in passive region the breakdown of passive film results from shear stress, the higher of load and the more positive of potential, the more removal of material will be. So anodic protection is not suitable for corrosive wear of alloys.

The reactions of two typical commercial phosphoric acid series rust control coatings with both α-Fe and rust (α-,γ-,δ-,am-FeOOH; α-, γ-Fe_2O_3 and Fe_3O_4)have been studied by Mossbauer spectroscopy. Since the active ingredient of the coatings is phosphoric acid, a 20％ H_3PO_3 alcoholic solution is adopted in place of the real rust control coatings. It is shown that, with the exception of the product for Fe_3O_4 being Fe(Ⅲ) amorphous phosphate, those for α-Fe and almost for all of the rest iron oxides and iron oxyhydroxides are iron acid phosphate FeH_3(PO_4)_2·2 1/2 H_2O. In addition to Fe (Ⅲ) products, various highspin Fe(Ⅱ) products have also been found in the products for α-Fe and Fe_3O_4. The process and the structure of the reaction products have been influenced by salt,water etc. from the environment. For the transfortion of Fe(Ⅱ) phosphate to Fe(Ⅲ) phosphate, sufficient O_2 is required. The results obtained is explained by two different precipitation mechanisms, namely, nucleating growth and high polymers aggregation.

The anodic polarization behaviour of FeNiCrPB amorphous alloy in acidic Cl~- containing solutions is studied, The results show that the alloy is insusceptible to pitting and its protection potentials are very noble. These properties are attributed to the anodic passive film which has a multilayer structure. It is shown by XPS analysis that a considetable amount of oxygen is adsorbed on the outer surface of the passive film and its inside layer consists of phosphate, hydroxides and oxides of chromium and iron.

A simple preoxidizing treatment added between two processes of coat treatment and diffusion treatment increased considerably hot corrosion resistance of a series of ASL-3 type Al-Si coatings, but did not damage any mechanical properties of coating/substrate system. The analyses results indicated that the preoxidizing treatment led to the formation of a dense and thin Al-and Si-rieh oxide film on the surface of the coating. The presence of SiO_2 within the film accounted for the superior hot corrosion resistance of the coating.

An investigation of the boride phase in high boron stainless steel has been carried out in an attempt to account for its corrosion behaviour in sulphuric acid. The anodic disolution process of the high-boron stainless steel has been revealed by electrochemical and surface analytical techniques. The corrosion model of high-boron 18CrSNi type alloys in sulphuric acid has been proposed in this article.

The change of corrosion fatigue(CF) fractography with stress ratio (R) and frequency (f) were studied in distilled water and 3.5％ NaCl aqueous solution. It is shown that the variations of CF fractography with increase in R or decrease in f are similar, i. e., the tendency of stress corrosion cracking (SCC)fractography increased with increase in R or decrease in f on CF fractography. A mechanism schetch map of crack propagation which indicated the influence of R and f on CF cracking mechanism was presented.

An investigation on SCC behavior of 1Cr18Ni9Ti austenitic stainless steel and its ion-nitrided samples has been carried out by constant loading tensile test, electrochemical method and acoustic emission technique. The result shows that the ion-nitriding process is an effective measure for improving the SCC resistance in chloride medium. Local nitriding on stainless steel can also postpone the initiation of SCC. A new explanation on mechanism of improving SCC resistance of stainless steel by nitriding is described in this paper. It is suggested that the main cause for improved SCC resistance stainless steel is the shift of corrosion potential below the critical cracking potential (just after the establishment of galvanic couple) rather than the compressive stress induced on the surface layer by nitriding.

Under conditions of simulating dip-soldering and wave-soldering, the oxidizability and solderability of molten NG solder developed recently by the authors were investigated and compared with those of HLSnPb39 and H63A solders made in Japan. The drossing weight of NG solder was about onefourth of that of HLSnPb 39 or H63A solder, which showed that NG solder was better than the other two solders in anti-oxidation. Experiments also showed that the wettability of NG solder was 40％ larger than that of HLSnPb39 solder. Results examined by SEM and AES show that the additional element Ga is highly enriched on the surface of NG solder. A dense and very thin film exists on the surface.

The effects of non-aggressive anions Mp (NO_3~(2-), CrO_4~(2-), SO_4~(2-))in sodium chloride solution on the critical pitting potential E_c of a thin aluminum film in integrated circuit were studied. It was found that these ions shifted E_c to more noble values and, up to a given concentration of chloride, E_C and [Mp], followed the relation: E_c=a+blog[Mp]. From the preceding relations for several concentration of chlorides, an equation log[Cl~-]=Alog [Mp] +B was obtained. The efficiency of inhibition decreased in the order: NO_3~->CrO_4~(2-)》SO_4~(2-). It was supposed that the cause of inhibition was the reversible competitive adsorption of non-aggressive anions with chloride ion, and the difference of inhibition efficiency depended mostly on the oxidation ability of these anions.

Diffusion of the medium in the polymer plate material of the lining with variable thermo-diffusivity was discussed in-the paper. By means of weighted residuals, a general approach for the N-th approximation was achieved. The second approximation of the concentration was achieved, and the relation between the temperature and the plate life time was established on the basis of specific examples.

The inhibitive action of K_2CrO_4 as an inhibtor for aluminium in H_3PO_4(1.0～5.0M) has been investigated between 30℃-50℃ by means of weight loss method. Curves drawn for reaction rates led to a kinetic expression for which the various parameters (K, A, B, E) were calculated. The inlaibitive characteristic of K_2CrO_4 on aluminium in H_3PO_4 was discussed.

The wear resistance of Co-26Cr-3Mo-2.5C alloy is shown to be related to the presence of precipitated particles. The long time oxidation dynamics at different temperatures was studied. Results indicate that there is a linear relationship at 700,800 and 900℃ either between weight gain in oxidation and time or detween the amount of the exfoliated oxides and time. When oxidized for 500 hours at 700℃, the oxides are mainly Co_3O_4 and Cr_2O_3 (also CoCr_2O_4 in minor amounts). Above 800℃, CoCr_2O_4 becomes the main oxide.

It is generally thought that in electrodeposition,the primary distribution of current in an electrolyte is determined by Ohm's law, The author points out in this paper that primary distribution of current is not only determined by Ohm's Law, but also by the law of current refraction, In the light of this idea, the author has derived a formula for the throwing power,and has pointed out some conditions which must be tak.en into consideration when using the formula.