【摘要】 过渡金属硅化物Cr₃Si具有熔点高、高温蠕变性能好、高温抗氧化性能及抗热腐蚀性能优异等特点。本文以Cr—Si—Ni高纯预合金化粉末为原料、利用激光熔敷技术在奥氏体不锈钢1Cr18Ni9Ti表面上制得了以金属硅化物Cr₃Si为增强相、以复杂多元金属硅化物Cr₂Ni₃Si为基体的快速凝固金属硅化物复合材料冶金涂层,分析了该涂层的显微组织,在高温及常温干滑动磨损条件下测试了其耐磨性能。研究结果表明,由于涂层中硬质耐磨相Cr₃Si的抗磨骨干作用,在高温及常温干滑动磨损条件下该涂层均具有优良的耐磨性能。更多还原

【Abstract】 Because of its outstanding combination of low density. high melting point, excellent elevated -temperature creep strength and high - temperature oxidation resistance, the transition metal silicide Cr3Si is considered as one of the promising candidate high - temperature structural materials for the aerospace industries. From a tribological point of view, the very high hardness up to temperatures of 1200℃. abnormal hardness -temperature relationship inherent to intermetallic compounds, excellent high - temperature oxidation resistance and unique metallic - covalent mixed atomic bonding make Cr3Si - base alloy an excellent elevated - temperature wear - resistant material. However, as far as the authors know, no literature has been published on the high -temperature wear resistance of Cr3Si metal silicide alloys as coating materials. In this paper, a rapidly solidified high -temperature wear resistant Cr2Ni3Si/Cr3Si metal silicide composite coating was fabricated on substrate of an austenitic stainless steel by laser cladding using Cr - Si - Ni elemental powder blends. Because of the presence of large amount of hard, wear and oxidation resistant primary Cr3Si dendrites, the laser clad Cr2Ni3Si/Cr3Si metal silicide composite coating has excellent wear resistance under high temperature and room temperature sliding wear test conditions.更多还原