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铌基金属间化合物是一种潜在高温结构材料,室温脆性大。用Nb-12Ti-22Al和Nb-40Ti-15Al两种混合粉末,经激光沉积分别合成制备了A15-Nb3Al金属间化合物脆性涂层和韧性B2结构合金涂层。通过对制备工艺的研究,基本实现了每层成分和层厚的控制,利用韧脆相间层层叠加方法用激光制备出不同层厚比的脆韧相间A15-Nb3Al/B2叠层结构金属间化合物基复合材料。叠层复合材料的元素成分、显微组织和显微硬度均呈周期性变化,界面存在渐变过渡。叠层结构Nb基金属间化合物复合材料具有良好的室温和高温强度,性能呈各向异性。随着脆韧层厚比的增大,叠层复合材料的强度增加,在水平、竖直两方向的室温屈服强度最高分别可达1030 MPa和871 MPa,900℃屈服强度最高分别为301 MPa和267 MPa。
Niobium-based intermetallics are potentially high-temperature structural materials that are brittle at room temperature. A15-Nb3Al intermetallic compound brittle coating and ductile B2 structural alloy coating were prepared by laser deposition using two mixed powders of Nb-12Ti-22Al and Nb-40Ti-15Al. Through the research on the preparation process, the composition and thickness of each layer were basically controlled. The A15-Nb3Al / B2 multilayer intermetallic compound with different layer thickness ratio was prepared by lamellar method Matrix composite materials. The elemental composition, microstructure and microhardness of the laminated composites show periodic changes, and the interface has a gradual transition. Laminated structure Nb-based intermetallic compound composite has good room temperature and high temperature strength, anisotropy. With the increase of brittle-to-ductile layer-thickness ratio, the strength of laminated composites increases. The highest yield strength at room temperature in both horizontal and vertical directions is up to 1030 MPa and 871 MPa, and the highest yield strength at 900 ° C is 301 MPa and 267 MPa.