E. T. McDevitt, Allegheny Technologies Incorporated (ATI), Monroe, NC; W. D. Cao, ATI Allvac, Monroe, NC
There is increasing interest in the use of precipitation hardened high strength stainless steels in aerospace structural applications in order to reduce corrosion related repair costs. However, the corrosion behavior of many of these steels has not been well characterized. This presentation compares the corrosion behavior of Allvac S240, Allvac 13-8 SuperTough, 15-5 PH, and Custom 465 in accelerated tests. The alloys were evaluated for free corrosion (ASTM G31) and crevice corrosion (ASTM G78) resistance in a simulated sea water environment. Electrochemical tests (ASTM G59 and ASTM G5) were conducted to compare the free corrosion potential, the passive film breakdown potential, and corrosion rate of the four alloys. The important corrosion mechanisms for each alloy will be discussed. In addition, stress corrosion cracking behavior of 13-8 SuperTough and S240 is reported.
Summary: This presentation compares the corrosion behavior of Allvac S240, Allvac 13-8 SuperTough, 15-5 PH, and Custom 465 in accelerated tests. In addition, stress corrosion cracking behavior of 13-8 SuperTough and S240 is reported.
