纳米SiC对Ti(C,N)基金属陶瓷微观组织与性能的影响

Nano-SiC addition on microstructure,mechanical properties and high temperature oxidation resistance of Ti(C,N)-based cermets

以Ti(C,N),WC,Mo2C,TaC和Cr2C3等粉末为主要原料,Co和Ni作为粘结剂,添加0~11%(体积分数)的纳米SiC粉末作为增强相,制备Ti(C,N)基金属陶瓷,研究SiC含量对陶瓷材料显微组织、力学性能和高温抗氧化性能的影响。结果表明,少量SiC不会改变金属陶瓷原有的相结构,而随SiC含量增加,环形相的完整性下降,硬质相的平均晶粒尺寸减小。SiC体积分数为5%的Ti(C,N)基金属陶瓷综合性能较优异,硬度(HRA)为88.8,抗弯强度为2280 MPa,断裂韧性为13.22×10^3 kN·m^−3/2。添加SiC可增强Ti(C,N)基金属陶瓷的高温抗氧化性能,氧化后材料表面生成致密的SiO2膜层。

Ti(C,N), WC, Mo2C, TaC and Cr2C3 powders were used as the main raw materials, Co and Ni powders were used as binders, and nano-SiC powders with 0-11% volume fraction were added as the reinforcing phase to prepare Ti-(C,N) based cermets.The effect of SiC content on the microstructure, mechanical properties and high temperature oxidation resistance of ceramic materials was studied.The results indicated that a small amount of SiC could not change the original phase structure of the cermet.As SiC content increased, the integrity of the ring phase decreased and the average grain size of the hard phase reduced.Ti(C,N)-based cermet with 5% volume fraction SiC had excellent comprehensive properties, with Rockwell hardness of 88.8 HRA, flexural strength of 2 280 MPa, and fracture toughness of 13.22×10^3 kN·m^-3/2.The addition of SiC enhanced the high temperature oxidation resistance of Ti(C,N) based cermets and produced a dense SiO2 film on the surface.