热变形双相不锈钢的微区取向及组织分析

 在变形温度为1000和1100℃，应变速率为01s-1的条件下，利用MMS-200热模拟试验机，对S32750超级双相不锈钢进行了高温压缩试验。利用电子背散射衍射(EBSD)分析了其晶体取向和微观组织。研究结果表明，铁素体在两种试验条件下均可形成<001>和<111>∥压缩轴织构，在变形温度为1100℃时，<001>织构要强一些；奥氏体在两种变形温度下均形成了<001>织构，强度很弱。在变形温度为1100℃条件下，奥氏体中存在的以Σ3为主的CSL特殊晶界数量更多。两种试验条件下，S32750超级双相不锈钢中铁素体和奥氏体均发生了动态再结晶，降低变形温度有利于细化晶粒。在铁素体向奥氏体转变过程中，奥氏体可以在铁素体晶界处生成，也可以在铁素体晶粒内部形成。

Local Orientation and Microstructures Analysis of Hot Deformed Duplex Stainless Steel

The hot compression test of S32750 super duplex stainless steels were investigated through MMS-200 thermal-mechanical simulator with the temperature of 1 000 and 1 100 ℃ and the strain rate of 0.1 s-1,and electron backscattered diffraction(EBSD) techniques were applied to reveal grain orientation and microstructures.The results show that ferrite orientations exhibit <001> and <111> texture at two different conditions,and texture intensity is larger at the deformation temperature of 1 100 ℃.Austenite orientations exhibit <001> texture at two different conditions,but both texture intensities are weak.More Σ3 coincidence site lattice(CSL) special grain boundaries are obtained at the temperature of 1 100 ℃.Dynamic recrystallization of ferrite grains and austenite grains are detected in the tested steels at two different test conditions,and finer grains are obtained at lower deformation temperature.Austenite formation is observed at ferrite grain boundaries and grains interior.