合金铸铁聚焦光束表面强化技术

采用灯幅射聚焦光束做热源对合金铸铁进行表面熔凝处理，研究了熔凝处理层的组织和性能特点及光束工艺参数对组织和性能的影响。研究表明，采用聚焦光束熔凝正理２技术可在合金铸铁表面获得一个深度为毫米级、硬度为ｍ８５０的强化层，调节功率密芳和扫描速度可有效控制强化工和宽娄输入功率为５ｋＷ，扫描速度为３．５ｍ／ｈ时，一次熔凝正理２宽度可达１２ｍｍ。经光束熔凝处理后的合金铸铁组织有分层现象，采用较低的扫描速度时，

Surface Hardening of Alloy Cast Iron with Light Beam

Surface melting of alloy cast iron with the light beam of a xenon lamp, microstructures and properties of melted layer and the influence of light beam parameters on them were investigated. The results show that melted layer of white iron with a depth of millimeter level and micro hardness of 850 kgf/mm 2 can be obtained on the surface of cast iron by using the light beam. The depth and width of melted layer can be controlled effectively through adjusting the density of light power and scan rate. A single pass melting width can be up to 12mm, when the input power is 5kW and scan rate is 3.5m/h. The light beam melted zone of alloy cast iron obtains a lamellar structure. At the lower scan rate the melted layer consists of a carbon poor zone with very low hardness in its surface, a sub eutectic ledeburite in its middle and a mixture with ledeburite and graphite eutectic at its bottom. The lose of carbon can decrease with increasing of light beam scan rate and therefore the carbon poor zone is inhibited.