【摘要】 观测了激光熔敷NiCrBSi合金涂层的显微结构,研究了涂层与不锈钢基体的结合方式和时效处理对其组织结构和显微硬度的影响.用5kW连续二氧化碳激光器对不锈钢上等离子喷涂NiCrBSi合金层进行重熔。涂层的显微结构为细化树枝晶,由γ基体与γ/γ＇和NiB的共晶组成。面心立方γ基体晶格常数是0.3572nm。时效处理后的合金层由析出γ＇沉淀强化相的针状和羽毛状马氏体组成,时效使显微硬度值显著提高。更多还原

【Abstract】 A 5 kW CW C02 laser was utilized to prepare NiCrBSi alloy coatings on stainless steel. Powders were preplaced by plasma-spraying. The microstructure of the coatings are fine dendrites, which are composed of rrrrrrrrrrr matrix phases and eutectic phases including 7/7’ and NiB phases, lattice parameter of fee 7 matrix is 0.3572 nm. The coating process provides a route to refine microstructure, as laser scanning speed increases from 5 to 20 mm/s, the space between dendrites decreases from 10 to 3.8 /xm. NiCrBSi coatings after ageing treatment were composed of pinhole and plumy martensite, the precipitation of 7’ phase increase the microhardness values of alloy coatings.更多还原