Micro-FAST制备WC-TiC-Co硬质合金的性能和组织研究

Properties and Microstructure of WC-TiC-Co Cemented Carbide Prepared By Micro-FAST

将多物理场耦合活化烧结技术(Micro-FAST)和燃烧合成技术相结合,在WC-8Co原始粉末中加入一定量的Ti粉和C粉,通过原位合成了TiC,制备了尺寸为φ4 mm×4 mm的WC-TiC-Co微型圆柱硬质合金。研究了工艺参数对硬质合金性能和组织的影响。结果表明,WC-8Co-4Ti-2C和WC-8Co-6Ti的样品在成分检测中均检测出TiC相,同时还伴随着(W,Ti)C相的生成。WC-8Co-4Ti-2C和WC-8Co-6Ti的样品致密度随着烧结温度的增加而增加,最高可达到96.82%;同时,试样的微观孔隙减少。显微硬度及断裂韧性均随烧结温度的增加而减小,显微硬度最高可达1936.7 HV30,断裂韧性最高可达8.0270 MPa·m^(1/2),整体上WC-8Co-6Ti样品的力学性能要优于WC-8Co-4Ti-2C样品的。

Combining micro-FAST with combustion synthesis,WC-TiC-Co cemented carbide withφ4 mm×4 mm was prepared by adding a certain amount of Ti powder and C powder into WC-8Co raw powder through in situ synthesis of TiC.The effect of process pararmters on the microstructure and properties of cemented carbide was studued.The results show that the TiC phase and the(W,Ti)C phase are detected in both WC-8Co-4Ti-2C and WC-8Co-6 Ti sintering samples.The density of the samples increases with the increase of sintering temperature in both WC-8Co-4Ti-2C and WC-8Co-6Ti sintering samples,and the maximum value can reach 96.82%.Meanwhile,the micro porosity of the samples reduces.Both the microhardness and fracture toughness decrease with the increase of sintering temperature.The maximum microhardness can reach 1936.7 HV30,and the maximum fracture toughness can reach 8.0270 MPa·m1/2.On the whole,the mechanical properties of WC-8Co-6Ti samples are better than that of WC-8Co-4Ti-2C samples.