摘要
利用横流 CO2 激光器在 38Cr Mo Al表面激光宽带熔覆 Ni Cr BSi+ WC(重量百分比 2 5% )复合涂层 ,用扫描电镜观察组织形貌 ,用 X射线衍射仪进行物相分析 ,用磨擦磨损实验机进行耐磨性实验 ,并对多层熔覆工艺进行了初步的探讨。结果显示 ,合金层与基体成良好的无裂纹气孔的冶金结合。表面耐磨性与工艺参数具有一定对应关系 ,且 2 .2 k W时的耐磨性最高 ,为氮化工艺的 2 .9倍。多层熔覆试验能形成厚度可调的无裂纹熔覆层 ,对生产工件的修复具有实际意义。
NiCrBSi+25wt.%WC composite coatings were produced by laser cladding on a 38 CrMoAl substrate with a transversal flow CO 2 laser. Microstructure and wear properties of the coatings were investigated by means of SEM, XRD, and Wear Testing Machine. The multi-layer laser cladding technology was preliminarily discussed. The results show that the composite coatings have better metallurgical bond to the substrate, both crack and air hole are not found. Wear resistance of the coatings has certain corresponding relation with laser clad parameter, the wear resistance reaches the maximum value when the laser power is 2.2kw, it is 2.9 times that of the sample treated by nitriding. The coatings with varied thickness and crack-free can be obtained by multi-layer laser cladding, which will have practical significance for repairing workpieces.
出处
《激光与光电子学进展》
CSCD
2001年第5期26-31,共6页
Laser & Optoelectronics Progress
