Stress corrosion cracking of vessels and pipes for alumina processing in aggressive caustic solutions

摘要

The paper presents results of the experimental investigation of the role of strain rate and temperature on stress corrosion cracking (SCC) of mild steel at elevated temperatures. For investigation of SCC-susceptibility, slow strain rate tests were earned out at various strain rates (in the range of 0.12 X 10~(-6)-0.55 X10~(-6) s~(-1)) in an industrial caustic solution and an inert environment (liquid paraffin) at 90 and 150 deg C. The mode of the SCC crack propagation and the fractographic details of the specimens tested in the two environments have been compared. The investigation suggests susceptibility of the mild steel to SCC in the given caustic solution at 150 deg C only when the tests were earned out at a strain rate <0.25 X 10~(-6)s~(-1), and no susceptibility at 90 deg C.