【摘要】 本文利用Gleeble—1500型热/力模拟机研究了锅炉用ASTM A290钢形变奥氏体的动态再结晶规律及组织变化特点。提出了一种新的数学处理方法直接求解热变形方程中的激活能（Q）等常数,得出A299钢的Q值为369.3 KJ·mol^-1。在此基础上给出了A299钢的动态再结晶图。试验发现,该钢奥氏体完全动态再结晶后的晶粒尺寸(d_SS)与Zener-Hollomon参数间存在指数关系:d_SS=3.41×10³×Z^-0.165。A299钢奥氏体形变后立即淬火时,发生形变促发铁素体转变的临界条件为Z=4×10¹⁵S^-1。更多还原

【Abstract】 The dynamic recrystallization （DRX） and strain induced austenite （A）→ferrite （F） transformation of steel ASTM A299 have been investigated with Gleeble-1500 thermal mechanical simulator. A new mathematical method is used to calculate the activation energy Q (369.3 kJ·mol^-1) and other hot deformation parameters, and the DRX disgram of steel A299 is given. It is found that the relationship between stable state grain size of austenite d_ss and Zener-Hollomon parameter Z obeys the power law d_ss=3.41×10³×Z^-0.165 and the A→F transformation is induced by the deformation of austenite, the critical condition for strain induced A→F transformation is Z=4×10¹³ s^-1 when austenite is quenched immediately after deformation.更多还原