回火温度对2Cr13不锈钢应力腐蚀开裂和力学滞后的影响

Effect of tempering temperature on stress-corrosion cracking and mechanical hysteresis of 2Cr13 stainless steel

采用慢应变试验法（SSRT）测试了2Cr13不锈钢在1020℃淬火及不同回火温度条件下的应力腐蚀开裂（SCC）特性,并利用电阻应变计传感器设计原理,测试了回火温度对2Cr13钢力学滞后的影响。结果表明,在270～420℃回火区间,随着回火温度升高,2Cr13钢强度略有增加,滞后略微减小,而应力腐蚀抗力则显著降低。分析认为,在试验温度区间,随温度升高,回火温度接近2Cr13钢敏化和第一类回火脆性温度,加之二次硬化效应,使得该材料应力腐蚀抗力随回火温度升高而显著降低;2Cr13钢力学滞后和其强度及亚结构有关,滞后误差随着材料强度增加而减少。

The stress-corrosion cracking （SCC） characteristics of 2Cr13 stainless steel quenched from 1020℃ and tempered at different temperatures were tested by slow strain rate test （SSRT） method. Meanwhile, the strain gage based load cell technique was employed to investigate the mechanical hysteresis of 2Cr13 stainless steel after tempering. The result shows that from 270 to 420℃, with increasing tempering temperature, the strength and mechanical hysteresis of 2Cr13 stainless steel slightly increases and reduces, respectively, along with a substantial increase of the susceptibility of SCC. It indicates that in the range of 270 to 420℃, with increasing tempering temperature, which is closer to the sensitization and tempering embrittleness temperature of 2Cr13 stainless steels, added to secondary hardening effect, by which the resistance of SCC of 2Cr13 stainless steel considerably decreases with increasing tempering temperature. Mechanical hysteresis of 2Cr13 stainless steel is related to the microstructure and strength, hysteresis error decreases with increasing materials strength.