激光熔覆工艺参数对铁基合金单道涂层成形质量的影响

The influence of laser cladding process parameterson the forming quality of single pass coatings on iron-based alloys

为探究激光熔覆工艺参数对铁基合金单道涂层成形质量的影响,在42CrMo钢表面激光熔覆Fe45合金涂层,利用正交实验得出最佳熔覆工艺参数,并分析工艺参数对单道熔覆层几何尺寸、稀释率和显微硬度影响程度的主次。利用单因素控制变量法,探究工艺参数对熔宽、稀释率、显微硬度的影响规律。结果表明,最佳熔覆工艺参数——激光功率为1500 W,扫描速度为15 mm/s,送粉率为14 g/min;激光功率对熔深、熔宽、稀释率和显微硬度的影响最为显著,扫描速度对熔高的影响最为显著。当激光功率从1200 W增加到2100 W时,熔宽从1.78 mm增加到2.73 mm,稀释率从21%增加到67%;当扫描速度从6mm/s增加到15 mm/s时,熔宽从2.70 mm下降到2.19 mm,稀释率从42%下降到29%;送粉率对熔宽影响较小,熔宽保持在2.15 mm左右,送粉率在12~14 g/min时,稀释率下降明显,之后基本不变。实验制备的Fe45合金涂层的显微硬度是基体硬度的2.3倍,可显著提高轴类零件表面的耐磨性,延长其使用寿命。本研究可为制备成形质量良好的Fe基合金涂层提供理论指导。

In order to explore the influence of laser cladding process parameters on the forming quality of the single pass coating of iron based alloy,the laser cladding Fe45 alloy coating on the surface of 42CrMo steel was used to obtain the optimal cladding process parameters by orthogonal experiment,and the main and secondary influences of the process parameters on the geometry,dilution rate and microhardness of the single pass coating were analyzed.The influence of process parameters on melting width,dilution rate and microhardness was investigated by using the single factor controlled variable method.The results show that the optimal cladding parameters are 1500 W laser power,15 mm/s scanning speed and 14 g/min powder feeding rate.The influence of laser power on melting depth,melting width,dilution rate and microhardness is the most significant,and the influence of scanning speed on melting height is the most significant.When the laser power increases from 1200 W to 2100 W,the melting width increases from 1.78 mm to 2.73 mm,and the dilution rate increases from 21%to 67%.When the scanning speed increases from 6mm/s to 15 mm/s,the melting width decreases from 2.70 mm to 2.19 mm,and the dilution rate decreases from 42%to 29%.The powder feeding rate has little influence on the melting width,and the melting width is kept at about 2.15 mm.When the powder feeding rate is 12~14 g/min,the dilution rate decreases obviously,and then it is basically unchanged.The microhardness of the Fe45 alloy coating prepared by the experiment is 2.3 times than that of the substrate,which can significantly improve the surface wear resistance of shaft parts and prolong their service life.This study can provide theoretical guidance for the preparation of Fe-base alloy coatings with good forming quality.