摘要
采用真空烧结法制备了纳米SiC晶须增强Ti(C,N)基金属陶瓷复合材料,用XRD、FESEM、EDS、万能试验机及维氏硬度仪等手段研究了纳米SiC晶须对复合材料显微组织和抗弯强度及断裂韧度的影响。结果表明:复合材料的显微组织具有典型的"芯-壳"结构,主要由黑色的硬质核心相,灰色的环形相,灰白色的粘结相以及部分分布于外环形相/粘结相界面、部分弥散分布于粘结相中的白色增强相组成;随着纳米SiC晶须添加量的增加,粘结相的体积分数减小,增强相的体积分数增大;与未添加晶须的金属陶瓷相比,复合材料的抗弯强度和断裂韧度均有显著提高,当纳米SiC晶须的体积分数为7.5%时,复合材料的力学性能最佳,抗弯强度为2 346 MPa,断裂韧度为16.82 MPa·m^(1/2)。
The nano-SiC whisker reinforccxt Ti （C, N）-based cermets composite was fabricated with vacuum sintering technology. The effect of nano-SiC whisker on the microstructure, transverse rupture strength （TRS） and fracture toughness （KIC） was studied by XRD, FESEM with EDS, universal testing machine and Vickers hardness tester. The results show that the microstructure exhibited the classical ＂core-rim＂ morphology composed of black core phase, gray surrounding phase, grayish-white binder phase and white reinforced-phase which was partly distributed on the rim phase/binder phase interface and partly diffusely distributed in the binder phase. With the increase of amount of nano-SiC whisker addition , the volume fraction of binder phase decreased while the volume fraction of reinforced phase increased. The TRS and KIC of the composite were increased obviously respectively, comparing to Ti（C, N）-based cermet. When the nano-SiC whisker content was up to 7. 50%, the best mechanical properties with the TRS of 2 346 MPa and the KIC of 16. 82 MPa · m1/2 were obtained.
出处
《机械工程材料》
CAS
CSCD
北大核心
2009年第12期62-65,共4页
Materials For Mechanical Engineering
基金
国家自然科学基金重点基金资助项目(50634060)
国家自然科学基金资助项目(50074014)
