(1. 江西省科學(xué)院 江西省銅鎢新材料重點(diǎn)實(shí)驗(yàn)室，南昌 330029；
2. 中國(guó)石油大學(xué)(北京) 理學(xué)院，昌平 102249；
3. 南昌大學(xué) 材料科學(xué)與工程學(xué)院，南昌 330031)
摘 要: 采用電弧熔煉Ti、Ni和B的方法，原位合成B含量不同的3種NiTi-TiB2復(fù)合材料，對(duì)復(fù)合材料的顯微組織、成分及壓縮力學(xué)性能進(jìn)行研究。結(jié)果表明：材料中NiTi與TiB2之間為冶金結(jié)合，結(jié)合界面致密無孔隙，克服了以往研究中非原位復(fù)合材料常見的界面結(jié)合差以及致密度低等缺點(diǎn)。當(dāng)B的摩爾分?jǐn)?shù)超過6%以后，組織中出現(xiàn)粗大的Ti2Ni脆性枝晶，并伴隨材料壓縮性能的降低。樣品力學(xué)性能的惡化與粗大TiB2陶瓷以及Ti2Ni脆性枝晶的形成有關(guān)。
關(guān)鍵字: NiTi -TiB2；形狀記憶合金；原位合成；馬氏體相變
（1. Jiangxi Key Laboratory of Advanced Copper and Tungsten Materials,
Jiangxi Academy of Sciences, Nanchang 330029, China;
2. School of Science, China University of Petroleum-Beijing, Changping 102249, China;
3. School of Materials Science and Engineering, Nanchang University, Nanchang 330031, China）
Abstract:Three in-situ NiTi-TiB2 composites with different B contents were prepared by arc melting of Ti, Ni and B. The microstructure, composition and compress property were tested. The results show that TiB2 ceramic phase disperses in NiTi shape memory alloy matrix, with metallurgical bonding interface, and no pore is observed, which can overcome the shortcomings in traditional ex-situ composites, such as poor interfacial bonding, low density, porosity, and so on. However, the coarse TiB2 ceramic and brittle Ti2Ni dentrite with tens of micrometers size is observed when the B content is over 6% (mole fraction), which causes compression performance deterioration of the composite.
Key words: NiTi-TiB2; shape memory alloy; in-situ synthesis composite; martensitic transformation
