激光熔覆对38CrMoAl钢表面改性

研究了利用横流ＣＯ２激光器在３８ＣｒＭｏＡｌ表面激光器熔覆ＮｉＣｒＢＳｉ＋ＷＣ（２５％ｗｔ）复合合金层的组织、硬度与耐磨性。用扫描电镜观察组织形貌，用Ｘ射线仪进行物相分析，用摩擦磨损试验机进行耐磨性实验：合金层与基体成良好的无裂纹气孔的冶金。表面耐磨性与工艺参数具有一定的对应关系，且２．２ｋＷ时的耐磨性最高，为氮化工艺的７．８倍。

Effects of Laser Power on the 38CrMoAl Surface Properties of Laser Cladding Layer

The NiCrBSi+WC(25%) composite alloy layer was prepared on the 38CrMoAl substrate using laser cladding method with a high power transversal flow CO 2 laser.The morphologies and the microstructures of laser cladding layer were observed and the phase constitutions were identified.A model M 200 wear tester was used to characterize the wearability of the cladding layer.The experimental results indicate that the cladding layers were metallurgically adhered to the substrate with no cracks and porosities and there was a relationship between the wearability and the cladding conditions.The sliding wearability was highest when the laser power was 2.2kW,which was 7.8 times as that of the nitriding samples.