微波烧结温度对TiB_2钢结硬质合金组织及性能的影响  

Effects of microwave sintering temperature on microstructure and properties of TiB_2 steel bonded carbide

作　　者：苏倩[1] 刘成成[1] 罗军明[1] 黄俊[1] 

机构地区：[1]南昌航空大学材料科学与工程学院,江西南昌330063

出　　处：《材料热处理学报》2016年第11期113-117,共5页Transactions of Materials and Heat Treatment

基　　金：江西省铜钨新材料重点实验室(2011-TW-08);江西省科技攻关项目(2011BBE50010)

摘　　要：利用热力学分析Fe-Ti-B体系反应生成TiB_2的可能性,运用DSC曲线确定原位反应温度,并采用微波烧结技术原位合成TiB_2钢结硬质合金。通过光学显微镜、扫描电镜、能谱分析仪分析微波烧结温度对原位合成TiB_2钢结硬质合金组织的影响,采用显微硬度计和万能试验机对TiB_2钢结硬质合金的显微硬度及抗弯强度进行检测分析。结果表明:Fe-Ti-B体系在637.8℃即可发生原位反应,体系中反应生成物相主要为TiB_2和Fe_2B相。随着烧结温度的升高,硬质合金的密度、显微硬度和抗弯强度均先升高后降低,在1100℃时达到最大值,即相对密度、显微硬度和抗弯强度分别为97.5%、418 HV0.1和647 MPa。The possibility of Fe-Ti-B system reactions to generate TiB_2 was analyzed by the thermodynamics,and the in situ reaction temperature was determined by differential scanning calorimetry（ DSC） curves,then the TiB_2 steel bonded cemented carbide was synthesized by microwave sintering technology. The effects of sintering temperatures on microstructure of the TiB_2 steel bonded cemented carbide were researched by optical microscope,scanning electron microscopy and energy-dispersive spectrum. The microhardness and bending strength of the alloy were measured by microhardness test and universal testing machine. The results show that the sintering temperature of in situ reaction for Fe-Ti-B system is 637. 8 ℃,and the main phases of the reaction products are TiB_2 and Fe_2B. With the increasing of sintering temperature,the relative density,microhardness and bending strength of the cemented carbide increase first and then decrease,which reach their maximum at 1100 ℃,they are 97. 5%,418 HV0. 1 and 647 MPa,respectively.

关 键 词：原位反应 钢结硬质合金 微波烧结 TIB2 

分 类 号：TG135.5[一般工业技术—材料科学与工程]