PDF《烧结工艺和 Y2O3 添加量对 Ti(C,N)基》

第 卷第 期 中国有色金属学报 年月25

5 2015

5 Volume

25 Number

5 The Chinese Journal of Nonferrous Metals May

2015 文章编号:1004-0609(2015)-05-1277-08 烧结工艺和 Y2O3 添加量对 Ti(C,N)基 金属陶瓷显微组织和力学性能的影响 孙万昌,张佩,李攀,佘晓林,魏汉军,赵坤,张峰(西安科技大学 材料学院,西安 710054) 摘要:以TiC、TiN、Ni、Co 等粉末为主要原料,以稀土 Y2O3 为添加剂,采用无压烧结技术制备 Ti(C,N)基金 属陶瓷,研究烧结工艺和稀土 Y2O3 添加量对 Ti(C,N)基金属陶瓷显微组织和力学性能的影响.

结果表明:随着温 度的升高,TiC、TiN、WC、Cr3C

2、Mo 等相逐渐消失,向硬质芯相扩散发生固溶,经溶解?析出过程,最终形成 新的 Ti(C,N)硬质相和(Cr,W,Mo,Ti)(C,N)固溶体环形相,黏结金属 Ni 和Co 主要以 Ni 相、TiCo 和Co3W3C 中间相 的形式存在;

稀土 Y2O3 的添加未改变 Ti(C,N)基金属陶瓷烧结过程中的相结构演变过程,材料的显微硬度、抗弯 强度和断裂韧性均随 Y2O3 添加量的增加呈先增加后降低的趋势,当Y2O3 的加入量为 0.8%(质量分数)时,Ti(C,N) 基金属陶瓷的力学性能最佳,样品的显微硬度、抗弯强度和断裂韧性相比

1450 ℃烧结

50 min 样品的分别提高了 7.9%、45.8%和6.1%. 关键词:Ti(C,N)基金属陶瓷;

Y2O3;

烧结工艺;

力学性能 中图分类号:TG148 文献标志码:A Effects of sintering process and Y2O3 addition on microstructure and mechanical properties of Ti(C,N)-based cermet SUN Wan-chang, ZHANG Pei, LI Pan, SHE Xiao-lin, WEI Han-jun, ZHAO Kun, ZHANG Feng (College of Materials Science and Engineering, Xi'

an University of Science and Technology, Xi'

an 710054, China) Abstract: Ti(C,N)-based cermets were prepared by pressureless sintering method using TiC, TiN, Ni and Co powders as main raw materials and Y2O3 as additive. The effects of sintering process and Y2O3 content on the microstructure and mechanical properties of Ti(C,N)-based cermet were investigated. The results show that TiC, TiN, WC, Cr3C2 and Mo phases disappear gradually and diffuse into hard and rim phases by dissolution-precipitation process with increasing the sintering temperature, finally, new Ti(C,N) hard phases and (Cr,W,Mo,Ti)(C,N) rim phases are formed, while the bonding metals Ni and Co exist mainly in the form of Ni phases and the intermediate phases of TiCo and Co3W3C. The phase structure evolution of Ti(C,N)-based cermet almost has no change with adding Y2O3 during sintering process. The micro-hardness, bending strength and fracture toughness of Ti(C,N)-based cermet increase first, and then decrease with the increase of Y2O3 content. Ti(C,N)-based cermet achieves the best mechanical properties with 0.8% Y2O3 (mass fraction) addition, the micro-hardness, flexural strength and fracture toughness are increased by 7.9%, 45.8% and 6.1%, respectively, when compared to those of the sample sintered at

1450 ℃ for

50 min. Key words: Ti(C,N)-based cermet;

Y2O3;

sintering process;

mechanical property 随着我国经济的迅猛发展,在建筑、机械、石油、 化工、煤炭等众多领域对材料的需求越来越大,零部 件加工质量要求越来越高,服役状态下的性能可靠性 要求更为严格.因此,高效率、高质量的切削加工技 基金项目:陕西省科技攻关项目(2014K08-09);

国家自然科学基金资助项目(50172023);

2012 年榆林市产学研合作项目(2012YLCXY112) 收稿日期:2014-04-17;

修订日期:2015-01-06 通信作者:孙万昌,副教授,博士;