热燃烧温度对超重力场自蔓延离心熔铸TiB_2-TiC-(Ti,W)C组织及性能的影响  

Effects of Adiabatic Temperature on Microstructure and Properties of TiB_2-TiC-(Ti,W)C Prepared by Combustion Synthesis in High-Gravity Field

作　　者：娄光普 赵忠民[1] 

机构地区：[1]军械工程学院车辆与电气工程系机械制造教研室,石家庄050003

出　　处：《硅酸盐学报》2016年第12期1724-1728,共5页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(51072229);武器装备预研基金(9140A12040213JB34001)

摘　　要：通过在(Ti+B_4C)燃烧体系中引入WO_3+Al高能铝热剂,采用自蔓延离心熔铸方法制备TiB_2-TiC-(Ti,W)C复相陶瓷材料。结果表明,陶瓷是由规则的TiB_2片晶、TiC球晶以及(Ti,W)C固溶体组成,并发现少量Al_2O_3夹杂存在于陶瓷熔体中。随着铝热剂含量的增加,不仅提高了绝热燃烧温度,增进了陶瓷致密化,而且提高了陶瓷熔体中的W含量,提高了陶瓷硬度。TiB_2片晶诱发的裂纹偏转和桥接增韧大幅度提高了陶瓷的抗弯强度和断裂韧性。材料的硬度、抗弯强度和断裂韧性分别为24.6 GPa、584 MPa与20.3 MPa·m^(1/2)。当铝热剂添加过量,TiB_2相的含量下降,导致陶瓷力学性能有所下降。By introducing the （WO3＋A1） thermite to（Wi＋B4C） system, a series of TiB2-TiC--（Ti,W）C composites were achieved by SHS centrifugal casting. Results show that the ceramics are mainly composed of TiBz platelets, TiC spherocrystals and （Ti,W）C solid solution. Meanwhile, a few of A1203 inclusions are found in the ceramic. As the content of the thermite increases, not only increases the adiabatic temperature and promotes the densification of the solidified ceramic, but also increases the proportion of W in the ceramic and improves the hardness of the ceramic. The flexural strength and fracture toughness of the ceramic increase obviously because of the toughening mechanisms of crack deflection and crack bridging by TiB2 platelets. The Vicker hardness, flexural strength and fracture toughness of the ceramic are 24.6 GPa, 584 MPa and 20.3 MPa·m^1/2, respectively. However, excessive therrnite will reduce the mechanical properties of the ceramic due to the decrease of the TiB2 platelets.

关 键 词：二硼化钛基陶瓷 绝热温度 致密化 硬度 

分 类 号：TB331[一般工业技术—材料科学与工程]