The effect of NaCl-induced corrosion on Ti60′s hot salt stress corrosion cracking

The hot salt stress corrosion cracking (HSSCC) behaviour of Ti60 alloy at 600 °C in moist air has been studied, focusing on NaCl-induced corrosion as an embrittlement mechanism. NaCl-induced active corrosion was proven to happen at the crack front. This corrosion process promoted the loss of metal and the ingress of O, leading to quick O embrittlement of the alloy. In the alloy, the β phase can somewhat inhibit HSSCC due to its less sensitivity to corrosion-promoted O ingress. Phase boundaries have strong corrosion sensitivity to NaCl-induced corrosion. Thus, phase boundaries are prone to cracking.