SD成型剂对Ti(C,N)基金属陶瓷显微结构和力学性能的影响

Effect of SD binder on microstructure and mechanical properties of Ti(C,N)-based cermets

采用低压烧结的方法制备Ti(C,N)基金属陶瓷材料,并结合C、N、O分析,XRD、BSE、EDS等测试手段研究了SD成型剂对Ti(C,N)基金属陶瓷合金的C含量、相组成及显微结构和力学性能的影响。结果表明,随着SD成型剂添加量的增加,脱胶后压坯的C含量逐渐增加,N含量逐渐减小;烧结后Ti(C,N)基金属陶瓷由(Ti,Me)(C,N)(Me=W、Mo、Ta)和Ni/Co固溶体相组成;显微组织以黑芯-白环结构为主,并伴随着少量白芯-灰环的结构。SD添加量为100mL/kg时,Ti(C,N)基金属陶瓷材料的抗弯强度达1929MPa,硬度为1588HV30,添加量为180mL/kg时,合金组织中石墨相的出现使其抗弯强度大幅度下降。

Effect of SD binder on contents of carbon,phase composition,microstructure and mechanical properties of the Ti（C,N）-based cermets which prepared by the low pressure sintering technology were determined through chemical analysis,X-ray diffraction（XRD）,back scattering scanning electron microscopy（BSE） and energy dispersive spectrometer（EDS）,respectively.The conclusions are as follows： the total carbon content of cermets compacts after debinding increases and the nitrogen content decreases as the SD binder increases.There are only two phases,（Ti,Me）（C,N）（Me=W,Mo,Ta） and Ni/Co solid solution existing in the Ti（C,N）-based cermets after sintering.The alloy exhibits a big volume fraction of black core-white rim structure.Meanwhile,small amount of white core-grey rim structure also exists.The preferable synthetically mechanical properties with transverse rupture strength of 1929MPa and a hardness of 1588HV30 can be obtained when 100mL/kg of SD binder was added.When the addition of SD binder is 180mL/kg,the graphite phase appears,causing significant decrease in the transverse rupture strength.