回火温度对28CrMo47V钢组织和性能的影响

Effects of Tempering Temperature on Microstructure and Mechanical Properties of 28CrMo47V Steel

利用显微组织观察及力学性能测试等实验方法,研究了回火温度(610～650℃)对28CrMo47V钢组织及性能的影响。研究表明:610℃回火时,28CrMo47V钢的回火组织中完全保留了马氏体针叶形态,随回火温度升高组织中马氏体针叶形态逐渐减少,并在650℃回火后完全消失,得到回火索氏体;回火温度的变化亦显著影响钢材的性能,随回火温度升高,钢材的屈服强度及抗拉强度呈明显下降趋势,而冲击韧度显著提高;630℃回火时因组织的弥散强化及细晶强化可使28CrMo47V钢达到一个优良的强韧化综合效果。

The effects of tempering temperature（610-650 ℃） on the microstructure and properties were studied by microstructure observing and mechanical property testing.The results show that the microstructure is completely needle-like martensite when tempered at 610 ℃.The number of needle-like forms in martensite reduces with tempering temperature increasing,and disappears totally at 650 ℃.Then the tempered sorbite structure is obtained.The mechanical properties are affected significantly by the change of tempering temperature.The yield strength and tensile strength decrease significantly with tempering temperature increasing,but the impact toughness increases.The strength and toughness of 28CrMo47V obtains a better comprehensive performance because of the dispersion strengthening and the fine grain strengthening when tempered at 630℃.