Iron-base alloys corrosion

M. Janik-Czachor, AES Investigations of Passive Films on Iron and Iron Base Alloys, Corrosion, Vol 35, 1979, p 360-366... 

With cobalt historically being approximately twice the cost of nickel, cobalt-base alloys for both high temperature and corrosion service tend to be much more expensive than competitive alloys. In some cases of severe service their performance iacrease is, however, commensurate with the cost iacrease and they are a cost-effective choice. For hardfaciag or wear apphcations, cobalt alloys typically compete with iron-base alloys and are at a significant cost disadvantage. 

The resistance of a metal to erosion-corrosion is based principally on the tenacity of the coating of corrosion products it forms in the environment to which it is exposed. Zinc (brasses), aluminum (aluminum brass), and nickel (cupronickel) alloyed with copper increase the coating s tenacity. An addition of V2 to 1)4% iron to cupronickel can greatly increase its erosion-corrosion resistance for the same reason. Similarly, chromium added to iron-base alloys and molybdenum added to austenitic stainless steels will increase resistance to erosion-corrosion. 

Stress Corrosion Cracking and Hydrogen Embrittlement of Iron Base Alloys, NACE, Houston, Texas, (1975)... 

Table 7.33 Corrosion rack tests of nickel- versus iron-base alloys used in waste incineration...

Parkins, R. N., from Stress Corrosion Cracking and Hydrogen Embrittlement of Iron Base Alloys, Edited by R. W. Staehle, J. Hochmann, R. D. McCright and J. E. Slater, NACE, Houston, p601, (1977)... 

Speidel, M. O., Corrosion fatigue in Fe-Cr-Ni alloys , Proc. Int. Conf. on Stress Corrosion and Hydrogen Embrittlement of Iron Base Alloys , Unieux-Firminy. France, 12-16 June 1973. NACE-5, pp. 1071-91 (1976)... 

Preece, C. M., Proc. Ini. Conf. on Stress Corrosion Cracking and Hydrogen Embrillle-menl of iron Base Alloys, Unieux-Firminy, France, June 12-16 1973, NACE, Houston, 625 (1977)... 

Sato, 1976] N. Sato, Passivity and Its Breakdown on Iron and Iron Base Alloys, (Edited by R. W. Staehle and H. Okada), p. 1, National Association of Corrosion Engineers, Houston, (1976). 

Researchers have tried to fabricate plates using many different metals— mainly, stainless steel, aluminum alloys, titanium alloys, nickel alloys, copper alloys, intermetallic alloys, and metal-based composites such as carbon fiber-reinforced aluminum alloys, carbon fiber reinforced copper alloys, etc. [26]. Although Ta, Hf, Nb, Zr, and Ti metals show good corrosion resistance and chemical stability [6], the cost of fhese metals is too high for them to be used as materials in metal plates. That is why relatively cheaper iron-based alloys, particularly stainless steel, have been popularly studied as plate material. In the following secfions, we will infroduce sfainless sfeel (SS) and SS plates, which have been extensively investigated and show promise for the final applications [6,11]. 

At present the iron-based alloys diffusion saturation by nitrogen is widely used in industry for the increase of strength, hardness, corrosion resistance of metal production. Inexhaustible and unrealized potentialities of nitriding are opened when applying it in combination with cold working [1-3], It is connected with one of important factors, which affects diffusion processes and phase formation and determines surface layer structure, mechanical and corrosion properties, like crystal defects and stresses [4, 5], The topical question in this direction is clarification of mechanisms of interstitial atoms diffusion and phase formation in cold worked iron and iron-based alloys under nitriding. 

Corrosion resistance of structural iron-base alloys in high-temperature environments is typically achieved by formation of a continuous... 

Nelson, H.G. and Williams, D.P., Quantitative observations of hydrogen-induced, slow crack growth in a low alloy steel, in Stress Corrosion Cracking and Hydrogen Embrittlement of Iron Base Alloys, Staehle, R.W., Hochmann, J., McCright, R.D., and Slater, J.E., Eds., NACE, Houston, TX, 1977, pp. 390-404. 

Low-alloy steels are iron-based alloys containing less than a total of 12 wt% intentional alloying elements. They are all killed. Alloying enhances mechanical properties and/or improves corrosion resistance. 

C.S. Carter and M.V. Hyatt, Review of Stress Corrosion Cracking in Low Alloy Steels with Yield Strength below 150 KSI, Stress Corrosion Cracking and Hydrogen Embrittlement of Iron Base Alloys NACE 5, R.W. Staehle, J.H. Hochman, R.D. McCright, and J.E. Slater, Ed., National Association of Corrosion Engineers, 1973, p 524-600... 

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