Si_3N_4基陶瓷模具性能研究  

Property of Si_3N_4-based Ceramic Mould

作　　者：陈祥健[1] 罗兵辉[1] 张博[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《矿冶工程》2012年第3期115-119,共5页Mining and Metallurgical Engineering

基　　金：中国铝业公司科技发展基金项目(2008KJA19)

摘　　要：采用热压烧结法制备了热挤压模具用Si3N4陶瓷和Si3N4+Ti(C N)陶瓷,并利用SEM、TEM、急冷-强度法等手段研究了其力学性能、显微组织、抗热震性能及摩擦磨损性能。实验结果表明:Si3N4陶瓷具有较Si3N4+Ti(C N)陶瓷优异的力学性能和抗热震性能,其最大抗弯强度和断裂韧性分别达到1 130 MPa、12 MPa.m1/2,抗热震临界温差为750 K;两种材料在摩擦磨损过程中的主要磨损机制为磨粒磨损和粘着磨损;Si3N4陶瓷的摩擦系数在0.39～0.67之间,Si3N4+Ti(C N)陶瓷的摩擦系数在0.61～0.81之间(在100 N,60 min条件下能达到0.81);而两者的磨损率均在10-10mm3/(N.m)数量级上,相同条件下Si3N4+Ti(C N)陶瓷的磨损率较小。Si3N4 and Si3N4 ＋ Ti（ C N） ceramic materials for hot extrusion die were prepared by hot pressing sintering method. The mechanical properties, microstrueture, thermal shock resistance and wear resistance properties of the two ceramics were investigated by SEM, TEM, quenching-strength method and other methods. The results show that Si3N4 ceramic material possess better mechanical properties and thermal shock resistance than the Si3 N4 ＋ Ti （C N） material. The maximal bending strength and fracture toughness of Si3N4 reached 1 130 MPa and 12 MPa . m1/2, respectively. The critical temperature difference of thermal shock resistance of Si3N4 was 750 K. The main wear mechanisms were abrasive wear and adhesive wear. The friction coefficient of the Si3 N4 ceramic material changes in the range of 0.39 to 0.67. The friction coefficient of the Si3N4 ＋ Ti（ C N） ceramic material changes in the range of 0.61 to 0.81, which can reach 0.81 under the condition of 100 N and 60 min. The wear rates of the two ceramic materials are at the same order of magnitude of 10-10 mm3/（N .m）. The wear rate of Si3N4 ＋ Ti（C N） is smaller than that of Si3N4 under the same conditions.

关 键 词：热挤压模具 陶瓷材料 氮化硅基陶瓷 抗热震性能 摩擦磨损 

分 类 号：TQ174[化学工程—陶瓷工业]