论文部分内容阅读
利用热膨胀仪、同步辐射高能X射线衍射、XRD和TEM等对经淬火+两相区处理+不同温度回火处理的9Ni钢中逆变奥氏体含量、逆变奥氏体在室温单轴拉伸过程的形变诱导相变及其对强度的影响规律进行了研究.结果表明,经780℃淬火和680℃两相区处理后,实验钢中不含逆变奥氏体,而在随后的回火过程中产生一定量的逆变奥氏体.逆变奥氏体含量随回火温度的上升先升高而后降低,600℃回火时逆变奥氏体含量最高.在室温拉伸过程中,逆变奥氏体的形变诱导相变开始于宏观屈服之后,在颈缩前基本全部转变成马氏体,从而屈服强度随回火温度的升高先减小后增大,600℃回火时屈服强度最小;抗拉强度随回火温度的升高而增大,640℃回火时抗拉强度最大.
Using the dilatometer, synchrotron radiation high-energy X-ray diffraction, XRD and TEM on the quenched + two-phase zone treatment + tempering at different temperatures 9Ni steel austenite content, reverse austenite at room temperature uniaxial pull Deformation induced phase transformation and its influence on strength were studied.The results show that after the 780 ℃ quenching and 680 ℃ two-phase treatment, the experimental steel does not contain inverted austenite, but in the subsequent back In the course of the fire, a certain amount of transformed austenite is produced.The content of the transformed austenite first increases and then decreases with the increase of the tempering temperature, and the content of the transformed austenite is the highest when tempered at 600 ° C. During the stretching process at room temperature , The deformation-induced transformation of transformed austenite begins after macroscopic yielding and almost all changes to martensite before constriction, so the yield strength first decreases and then increases with the increase of tempering temperature, tempering at 600 ℃ When the minimum yield strength; Tensile strength increases with the tempering temperature increases, the maximum tensile strength at 640 ℃ tempering.