A Test Procedure to Evaluate the Relative Susceptibility of Materials to Stress Corrosion Cracking

摘要

A stress corrosion test procedure that employs electrochemical potentiostatic polarization techniques has been presented. A potentiostatic stress corrosion life curve (PSCLC) was developed for various materials. The PSCLC can be used to show the effect of galvanic coupling on stress corrosion cracking. The best material for resistance to stress corrosion cracking can be determined by superimposing the PSCLC for each specific material and then partitioning the specific potential range. Also, the orders of magnitude scatter band that are observed in time-to-failure data are explained by this test procedure. The time to failure has been shown to be dependent on the electrochemical potential that exists between the environment and the material. This potential dependency on SCC has not been accounted for in stress corrosion testing. (Author)