中文摘要：

NiTi形状记忆合金具有诸多功能特性,如超弹性、高阻尼性和形状记忆效应等,因而得到广泛应用。TiB2陶瓷具有高硬度、高耐磨性和高模量特性,但其脆性限制了其应用。将记忆合金与TiB2陶瓷复合,有望获得超常性能：兼具高强度、高模量、超弹性、高硬度、高耐磨等力学性能,以及因耦合而产生的崭新功能特性。采用电弧熔炼Ti、Ni、B的方法,原位合成NiTi-TiB2复合材料,对B含量不同的6种复合材料的可逆马氏体相变、显微组织、成分及硬度进行了初步探索。结果显示,NiTiB合金中含有NiTi记忆合金相以及Ti2Ni和TiB2陶瓷相。随着B含量升高,TiB2陶瓷相由线状变化为粗大的块状,并且Ti2Ni和TiB2陶瓷相含量也随之逐渐升高。NiTi基体具有良好的抑制裂纹扩展功能。含B量为4%、6%和14%样品的硬度都普遍高于二元NiTi记忆合金,其中含14%B样品最高硬度与陶瓷相当。

英文摘要：

NiTi shape memory alloys exhibit shape memory effect, superelasticity and high damping due to reversible thermoelastic martensitic transformation, and thus have assumed tremendous impor- tance in the fields of science and engineering. The presence of a TiB2 ceramic second phase within the SMA matrix may lead to a new composite with increased strength, stiffness, hardness and so on, and the martensitic transformation characteristics and functional properties of the composites can be modied by control of the particles. Six in - situ NiTi-TiB2 composites were prepared by arc melting of Ti, Ni and B, and the martensitic transformation behavior, microstructure, composition and HV hard- ness were tested. SEM results showed that TiB2 ceramic phase dispersed in NiTi shape memory alloy matrix. With the increasing of B content, the content of Ti2Ni phase gradually increased, and both Ti2Ni and TiB2 ceramic phase became coarser. The HV hardness of each sample was higher than the binary NiTi shape memory alloy,and the hardness of Ti46 5Ni39 5B14 （at. % ） sample is comparable to the ceramic.