Three different types of tensile strength (TS) 980 MPa grade advanced high-strength steels used in automotive applications, namely, 980MS ( martensite steel ), 980DP ( dual phase ) and 980QP ( quenching and par...Three different types of tensile strength (TS) 980 MPa grade advanced high-strength steels used in automotive applications, namely, 980MS ( martensite steel ), 980DP ( dual phase ) and 980QP ( quenching and partitioning) steels were examined. The delayed fracture resistance of the steels was evaluated using a U-bend test, slow strain rate test(SSRT) and a constant load tensile test. The results indicated that all the steels could pass the 300 h HC1 solution immersion test and none of the U-bend specimens was fractured in the test. However,the steels exhibited different susceptibilities to delayed fracture under SSRT and the constant load tensile tests. 980DP exhibited the highest resistance to delayed fracture among all the samples, while 980MS was found to be the most susceptible to delayed fracture.展开更多
文摘Three different types of tensile strength (TS) 980 MPa grade advanced high-strength steels used in automotive applications, namely, 980MS ( martensite steel ), 980DP ( dual phase ) and 980QP ( quenching and partitioning) steels were examined. The delayed fracture resistance of the steels was evaluated using a U-bend test, slow strain rate test(SSRT) and a constant load tensile test. The results indicated that all the steels could pass the 300 h HC1 solution immersion test and none of the U-bend specimens was fractured in the test. However,the steels exhibited different susceptibilities to delayed fracture under SSRT and the constant load tensile tests. 980DP exhibited the highest resistance to delayed fracture among all the samples, while 980MS was found to be the most susceptible to delayed fracture.