槽钢轧辊孔槽表面激光熔凝强化处理工艺研究

Study on Laser Remelted-Strengthening Process on the Aperture Surface of Grooved Roll

利用5 kW横流CO_2激光器开展槽钢轧辊孔槽表面激光熔凝强化处理工艺研究,结果表明经过激光熔凝处理,大型槽钢轧辊孔槽表层材料变得强韧化了,从硬度较低、耐磨性较差的珠光体+共晶碳化物+极少量莱氏体+球状石墨组织,转变为硬度较高、耐磨性较好的马氏体+下贝氏体+残余奥氏体+球状石墨组织,而且表层奥氏体晶粒度由粗大转变为细小,激光处理完全改变了大型槽钢轧辊原来的组织状态和性能,获得了预期的效果;上机使用后,轧辊使用寿命提高50%以上,同时提高了槽钢产品的产量和质量。

Laser remelted-strengthening process on the aperture surface of grooved roll was performed with a 5 kW continuous wave CO2 laser. The results showed that after the laser remelted-strengthening, the aperture surface layer material microstructure of large-scale grooved roll from a low hardness and bad wear resistant pearlite ＋ eutectic carbide ＋ extremely few ledeburite ＋ spheroid graphite, changed to a high hardness and good wear resistant martensite ＋ lower bainite ＋ residual austenite ＋ spheroid graphite; Moreover the surface layer austenite crystal grain size by transform from thick to tiny. So the laser processing obtained anticipated effect. The roll service life enhances above 50% by putting them into use, simultaneously raised the channel steel product output and the quality.