Ni-Ti合金对Ti(C,N)基金属陶瓷组织和性能的影响

采用粉末冶金方法真空烧结制备了添加Ni-Ti形状记忆合金的Ti(C,N)-Co系金属陶瓷,研究了Ni-Ti合金对Ti(C,N)基金属陶瓷显微组织和力学性能的影响。结果表明:未加Ni-Ti合金的Ti(C,N)基金属陶瓷的显微组织表现为经典的黑芯-灰壳组织,陶瓷相多为球形;而加入Ni-Ti后的金属陶瓷随着Ni-Ti加入量的增多,组织逐渐细化,出现了多边形的陶瓷相,陶瓷相与粘结相的界面呈现直线关系。同时,金属陶瓷的抗弯强度和断裂韧性随着Ni-Ti合金加入量的增多有明显的提高,而硬度基本保持不变;Ni-Ti合金的加入量为15wt%时金属陶瓷获得最好的力学性能。

Effect of Ni-Ti Alloy on the Microstructure and Properties of Ti(C,N)- based Cermets

Ti(C,N)-Co series cermets with the addition of Ni-Ti shape memory alloy are fabricated by vacuum sintering,using the powder metallurgy method,moreover the microstructure and mechanical properties are studied. The results show that Ti(C,N)-based cermets without Ni-Ti alloy present typical core-rim microstructure and nearly spherical shape of hard phase; the microstructure of cermets gets finer,and the shape of hard phase becomes multiangular with the increasing of Ni-Ti alloy,the interface between hard phase and binder phase presents line. While transverse rupture strength and fracture toughness of cermets have a great rise with the increasing of Ni-Ti alloy addition,but the change of hardness is not obvious; the cermets obtain the best comprehensive mechanical properties when the addition of Ni-Ti alloy is 15 wt%.