焊接热循环对X-60管线钢中第二相粒子的影响

Effect of Weld Thermal Cycles on Second Phase Particles in X-60 Pipe line Steel

利用萃取复型技术,对Ti-V-Nb微合金钢母材及模拟焊接粗晶热影响区中第二相粒子进行了研究。结果表明,母材中的粒子为含有Ti、Nb、V的碳氮化合物复合粒子,其尺寸均在100nm以下;粒子的形状不规则,不同粒子具有不同的成分。焊接热循环后,焊接粗晶区中仍保留了较多的粒子,但粒子尺寸显著增大,粒子的形状由母材中的不规则状变为方形,粒子的含Ti显著提高。

By using carbon extraction replica technology and welding therma l simulation, the second phase particles in parent metal,weld metal and simulate d CGHAZ of Ti-Nb-V microalloyed steel were investigated. Experiment results and analysis show that the particles in the steel are less than 100 nm, irregular in shape , and have a slight size-dependence in that the relative content of Ti in crease with the increase of particle size. A large quantity of carbonnitride par ticles are still in CGHAZ after welding cycle , the shape of remaining particles change from irregular shape to cubicle one, all the particle in CGHAZ was rich in Ti.