【摘要】 采用气氛加压烧结法制备Ti(CN)基金属陶瓷,探索以较小的烧结压力制备出较高致密度的Ti(CN)基金属陶瓷刀具材料,同时能够克服传统的热等静压(HIP)所带来的一些组织缺陷。研究结果表明,随着烧结压力的提高,Ti(CN)基金属陶瓷的孔隙率明显降低,硬质相之间的粘连程度加大;为了提高烧结压力而充入更多的氩气,导致冷却阶段延长,从而延长了烧结时间,使环形相变厚,粘结相平均自由程增大。这些微观结构的变化使得随着烧结温度的提高,材料的抗弯强度上升,而硬度降低;快冷处理使环形相变薄,粘结相固溶强化程度加强,孔隙率下降,从而材料的强度和硬度同时得到提高;在烧结压力为2 MPa,烧结末期经过快冷处理,得到了孔隙率为A04B00,微观结构中没有"粘结相池",抗弯强度为2278 MPa,洛氏硬度91.9的高性能金属陶瓷材料。更多还原

【Abstract】 Gas pressure sintering was used to manufacture Ti(CN)-based cermets.The way that can be used to manufacture the dense Ti(CN)-based cermets in a relatively low sintering pressure and overcome some structure flaw by HIP was studied.With the increase of sintering pressure,the porosities markedly decreased,the degree of coalescence among the hard phase particles increased,the rim phase grew thick and the mean free path of binder phase increased.Because of these varieties of microstructure,the bending strength increased and the hardness decreased with the increase of sintering pressure.By rapid cooling,the rim phase became thin,solid solution strengthening of the binder phase increased and the porosities decreased.These resulted the increases of bending strength and the hardness together.A dense Ti(CN)-based cermets without "the pool of the binder phase" were obtained in the sintering pressure of 2 MPa and by rapid cooling treatment,which porosity is A04B00,the bending strength is 2278 MPa,and Rockwell hardness is 91.9.更多还原