Ti811和TC4合金的热盐应力腐蚀行为研究

Hot-Salt Stress Corrosion of Titanum Alloys of Ti811 and TC4

研究了Ti811(Ti-8Al-1Mo-1V)和TC4(Ti-6Al-4V)两种钛合金对热盐应力腐蚀(HSSC)的敏感性.结果表明:Ti811合金对HSSC非常敏感,在相同条件下其热盐应力腐蚀临界应力(σHSSC)明显低于TC4合金,且低于同温度的蠕变强度,而TC4合金的σHSSC高于同温度的蠕变强度;两种合金在HSSC暴露过程中,明显遭受到盐腐蚀,腐蚀产生的氢扩散到基体中,致使合金发生脆化,从而降低合金的室温塑性.

The susceptibility to hot-salt stress corrosion（HSSC）of Ti811（Ti-8Al-1Mo-1V）and TC4（Ti-6Al-4V）alloys was investigated.The results showed that Ti811 alloy was susceptible to HSSC,and its critical stress of HSSC（σHSSC）was lower apparently than that of TC4 alloy.The σHSSC of Ti811 alloy was lower than its creep strength at the same temperature,but the σHSSC of TC4 alloy was higher than its creep strength at the same temperature.The two alloys suffered extensively from salt corrosion,while the formed hydrogen diffused into the titanium alloy matrix,resulting in embrittlement and thereby reduction of room temperature ductility of the alloys.