论文部分内容阅读
采用宽光束ＣＯ２ 激光，对灰铸铁进行相变硬化和熔凝强化处理，分析了两种工艺条件下铸铁组织强韧化机理．结果表明，相变硬化马氏体形态主要为针状，组织内存在微细孪晶结构；熔凝形成的莱氏体组织内弥散分布着未熔Ｆｅ３Ｃ及新生相Ｆｅ７Ｃ３ ．声发射试验表明，灰铸铁经相变硬化处理，其强韧性稍优于熔凝处理的结果．结合激光形成的温度场特点，对试验结果进行了讨论．研究方法包括透射电子显微镜、Ｘ射线衍射、声发射试验等．
The wide-beam CO 2 laser was used to deal with the phase transformation hardening and melting strengthening of the gray cast iron. The strengthening and toughening mechanism of the cast iron under the two conditions was analyzed. The results show that martensite phase transformation is mainly acicular, with fine twins structure in the microstructure. Unmelted Fe3C and newborn phase Fe7C3 are dispersed in ledeburite formed by fusion. Acoustic emission tests showed that the toughness of gray cast iron was slightly better than that of fusion treatment by phase transformation hardening. Combined with the characteristics of the temperature field formed by laser, the experimental results are discussed. Research methods include transmission electron microscopy, X-ray diffraction, acoustic emission testing and others.