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 借助于X射线衍射，研究了C、Mn、Cr和Ni 含量对304奥氏体不锈钢拉伸力学性能和应变诱发 马氏体相变倾向的影响。结果表明：C、Mn、Cr和Ni在允许的成分范围内变化，应变诱发α′马氏体相变倾向差异很大，这导致屈服强度和抗拉强度复杂的变化，尽管应变诱发α′马氏体相变使加工硬化速率提高，相变可以诱发塑性，但相变速率较快，相变倾向较大的钢塑性反而下降，此外，由于室温变形还增大热诱发马氏体相变倾向，从而限制了C、Mn、Cr和Ni下限钢在高精度和低温环境下构件的应用。

Strain induced Martensite Transformation and Effects onMechanical Properties in 304 Stainless Steel

By means of X ray diffraction technique, the effects of C、Mn、Cr and Ni on the tensile properties and the tendency of strain induced martensite transformation in AISI 304 stainless steel have been investigated. The results have shown that, even though the variations of C、Mn、Cr and Ni were restricted to the standard specification, there existed significant difference with respect to the stability of austenite，leading to the complex variation in yield strength and tensile strength. Despite increase in the rate of work hardening due to strain induced martensite transformation and transformation induced plasticity, the inferior ductility was caused by high rate of formation martensite in the steel with low C、Mn、Cr and Ni contents. Moreiover, the deformation at room temperature increased the tendency of thermally induced martensite transformation in steel with low C、Mn、Cr and Ni contents , which give rise to low precision of components and brittlement in the steels used in low temperature.