为提高45钢表面硬度,采用CO2激光器在45钢表面进行激光硼合金化处理,通过正交试验方法优化激光硼合金化工艺,研究合金层的组织和性能。结果表明:45钢激光硼合金化的最佳工艺参数为激光功率4 k W,扫描速度8 mm/s,KBF4的质量分数3%;经该...为提高45钢表面硬度,采用CO2激光器在45钢表面进行激光硼合金化处理,通过正交试验方法优化激光硼合金化工艺,研究合金层的组织和性能。结果表明:45钢激光硼合金化的最佳工艺参数为激光功率4 k W,扫描速度8 mm/s,KBF4的质量分数3%;经该工艺处理后的合金化层分为合金层、过渡区;合金层厚度约为860μm,组织为Fe2B及少量α-Fe,表层组织形态呈胞状,次表层呈树枝状,平均硬度为1 350HV0.1;过渡区厚度约为100μm,硬度从1 350HV0.1到230HV0.1呈梯度分布。展开更多
The article is devoted to surface hardening of steels by alloying with the use of laser energy. Two combined technologies were proposed: first—laser alloying by nitride-forming elements followed by nitriding, and sec...The article is devoted to surface hardening of steels by alloying with the use of laser energy. Two combined technologies were proposed: first—laser alloying by nitride-forming elements followed by nitriding, and second—the local laser alloying followed by metallization in atmosphere of ammonia. It is shown that laser alloying in continuous radiation forms a layer with a homogeneous fine-grained structure with thickness of 600 microns. The subsequent nitriding increases the microhardness of the surface layer of low-carbon steels to 20,000 MPa, increases wear-resistance in a 3 - 15 times and crack resistance in a 1.5 times. Two-stage technology of metallization allows getting diffusion layer on the surface of steels with the thickness, which is 1.5 - 2 times higher than after traditional metallization. In addition, this method of surface modification can significantly reduce the temperature of diffusion metallization and reduce the processing time to 3 hours. The optimal regimes of both technologies, which provide homogeneous multiphase diffusion layers with high hardness and wear resistance, were determined.展开更多
文摘The article is devoted to surface hardening of steels by alloying with the use of laser energy. Two combined technologies were proposed: first—laser alloying by nitride-forming elements followed by nitriding, and second—the local laser alloying followed by metallization in atmosphere of ammonia. It is shown that laser alloying in continuous radiation forms a layer with a homogeneous fine-grained structure with thickness of 600 microns. The subsequent nitriding increases the microhardness of the surface layer of low-carbon steels to 20,000 MPa, increases wear-resistance in a 3 - 15 times and crack resistance in a 1.5 times. Two-stage technology of metallization allows getting diffusion layer on the surface of steels with the thickness, which is 1.5 - 2 times higher than after traditional metallization. In addition, this method of surface modification can significantly reduce the temperature of diffusion metallization and reduce the processing time to 3 hours. The optimal regimes of both technologies, which provide homogeneous multiphase diffusion layers with high hardness and wear resistance, were determined.