Fe-Ni-Si-B-V激光表面快速熔凝非晶化

A Study of Glass-Forming Conditions of Laser Surface Melted Fe-Ni-Si-B-V Alloy

采用 5kW连续CO2 激光器 ,通过微区X射线衍射、金相显微镜和显微硬度分析 ,研究实现Fe4 0 Ni3 6 Si8 B14 V2 合金激光表面非晶化的条件。通过控制激光功率密度和激光扫描速度等参数 ,实现了Fe4 0 Ni3 6 Si8 B14 V2 合金表面非晶化。试验结果表明 ,激光功率密度和激光扫描速度是实现材料表面非晶化的重要条件。选择激光功率密度和激光扫描速度要综合考虑 ,既要保证熔池有足够大的冷却速度 ,以防止晶化 ;又要保证熔池内难熔质点和原始晶体完全熔化并使成分均匀 ,以防止非均质形核。当激光功率密度为 2 .7× 10 5W/cm2 ,激光扫描速度在 1.0～ 2 .0m/s的范围内 ,Fe4 0 Ni3 6 Si8 B14 V2 合金表面可实现单带扫描非晶化。

This paper deals with glass forming condition of laser surface melted Fe 40 Ni 36 Si 8 B 14 V 2 alloy by means of a CO 2 continuous laser with power of 5kW、metalloscope、X Ray diffraction and microhardness test.Amorphous surface layer can be produced by controlling the power density and the scanning speed of laser beam.The result shows that the power density and scanning speed are two important factors to produce glassy surface layers.In selecting the power density and the scanning speed,it must be considered that a high cooling rate is necessary to avoid crystalization and in the meantime a high temperature and a sufficient time are necessary to ensure the full melt of all the surface material.A single pass glassy layer on the surface of Fe 40 Ni 36 Si 8 B 14 V 2 alloy can be achieved using a power density of 2.7×10 5W·cm 2 and a range of scanning speeds form 1.0 m·s 1 to 2.0 m·s 1 .