激光沉积制备Nb_3Al基难熔金属间化合物研究  

Study of Nb_3 Al Intermetallics Prepared by Laser Deposition

作　　者：何金江[1] 钟敏霖[1] 刘文今[1] 张红军[1] 

机构地区：[1]清华大学机械系激光加工研究中心先进成形制造教育部重点实验室,北京100084

出　　处：《航空材料学报》2006年第5期1-5,共5页Journal of Aeronautical Materials

基　　金：国家自然科学基金(10477009)

摘　　要：通过控制激光功率使Nb-12Ti-22A l(at%)和Nb-22A l(at%)两种成分配比的混合元素粉末在Ti-6A l-4V基体上激光沉积合成了Nb3A l基难熔金属间化合物,并达到了预期设定的成分配比,其显微组织均匀细小,在-δNb3A l基体上分布着不同形态的β-Nbss。在合适的激光功率下,无裂纹的沉积层厚度有一定的限制,随着沉积厚度的增加,沉积层中残余拉应力增大,沉积薄壁件容易在底部发生断裂。由于Ti的添加使Nb-12Ti-22A l的的裂纹倾向性小于Nb-22A l。The Nb3Al intermetallics has been prepared from Nb-12Ti-22Al （at%） and Nb-22Al （ at% ） elemental powder blends by laser deposition on the substrate of Tl-6Al-4V. The laser power is important for successful synthesis. The average compositions of the deposited intermetallics are identical to the compositions of the elemental powder blend. The micrustructure consists of δ-Nh3Al matrix and fine β-Nbss phase. It is found that there is a critical thickness for laser deposited layers free of cracks. With increase of deposited thickness, the prepared sample is inclined to fracture at the bottom, and the Nb-22Al is easier to crack without tha addition of Ti.

关 键 词：激光沉积 难熔金属 Nb3Al Nb-Ti-Al 

分 类 号：TG146[一般工业技术—材料科学与工程]