Fe16Mn0.6C高锰钢高温拉伸过程原位观察

In-situ Observation of High-temperature Tensile Process of Fe16Mn0.6C High Manganese Steel

利用装配拉伸台的共焦激光扫描显微镜研究一种高锰钢（Fe16Mn0．6C）高温拉伸性能，并原位观察了拉伸过程中表面组织的变化。结果表明，Fe16Mn0．6C高锰钢在300～1100℃热变形时，抗拉强度由950MPa降低至30MPa左右；延伸率起初逐渐降低，在700℃达到最低值30％，900℃时增加至65％，并在1100℃时降低至32％。原位观察发现随着温度升高，孪晶难以形成，导致材料在700℃时出现塑性低谷。计算了Fe16Mn0．6c高锰钢的堆垛层错能，并据此分析了温度和孪晶形成的关系。

The high-temperature tensile process and the surface structure evolution of Fe16Mn0.6C, a kind of high manganese steel, were observed in-situ by using a confocal scanning laser microscope （CSLM） equiped with a tensile furnace. The results show that the steel＇ s tensile strength decreases from 950 MPa to 30 MPa when the thermal deformation temperature increases from 300℃ to 1 100%. The ductility decreases and attains the valley value of 30% at 700℃, and then increases to 65% at 900℃, and then decreases to 32% at 1 100℃. In-situ observation shows that twins are difficult to appear as the temperature increases, which leads to low ductility at 700℃. Based on the cal- culation of the stacking fault energy of Fe16Mn0.6C, the relationship between temperature and twins formation is analyzed.