合金元素Al对Laves相NbCr2显微组织及断裂韧性的影响  

Effects of Al on the Microstructure and Fracture Toughness of NbCr_2 Alloys

作　　者：郑海忠[1,2] 鲁世强[1] 祝建业[1] 周伟[1] 

机构地区：[1]南昌航空大学,江西南昌330063 [2]南京航空航天大学,江苏南京210016

出　　处：《稀有金属材料与工程》2009年第1期80-85,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(50474009);航空科学基金(05G56003);江西省自然科学基金(0350045);江西省材料科学与工程研究中心基金(ZX200401001)

摘　　要：采用机械合金化+热压烧结的工艺路线制备Laves相NbCr2合金,研究合金元素Al对其显微组织、力学性能,特别是韧化效果的影响。结果表明:合金元素Al主要占据了Laves相NbCr2金属间化合物中Cr原子的晶格位置。添加合金元素Al的Laves相NbCr2合金较未合金化的NbCr2硬度有所提高;当Al含量达到12at%时,断裂韧性要高于未合金化的NbCr2合金,达到了6.8MPam,远远高于熔铸合金的断裂韧性(1.2MPam)。NbCr2 alloys of Laves phase were prepared by mechanical alloying and hot pressing, and the influences of AI on the microstructure and mechanical properties, especially fracture toughness, of NbCr2 alloys were studied. The results show that the alloying element Al mainly exists in the Cr site in the NbCr2 Laves phase. The hardness of NbCr2 alloys increases slightly with the increase of Al adding amount, but no obvious effect on the fracture toughness for the NbCr2 alloys. At a higher Al adding level （i. e. 12 at%）, the fracture toughness of the NbCr2 alloy is 6.8 MPa√m a higher value than that of the cast alloys （1.2 MPa √m ）.

关 键 词：Laves相NbCr2合金化 断裂韧性 硬度 

分 类 号：TG113[金属学及工艺—物理冶金]