B_4C/Al复合材料力学性能及其断裂机理的研究  

Study on Mechanical Properties and Fracture Mechanism of B_4C/Al Composite

作　　者：彭可武[1] 吴文远[1] 徐璟玉[1] 涂赣峰[1] 

机构地区：[1]东北大学材料与冶金学院,辽宁沈阳110004

出　　处：《热加工工艺》2007年第4期1-3,37,共4页Hot Working Technology

基　　金：国家自然科学基金资助项目(50574031);高等学校博士点专项科研基金资助项目(20030145015);辽宁省科学基金资助项目(20021023)

摘　　要：对无压浸渗法制备的B4C/Al复合材料进行了力学性能测试。结果表明,B4C/Al复合材料的抗弯强度和断裂韧性与单一B4C材料相比有显著提高。B4C/Al复合材料的抗弯强度及断裂韧性分别比单一B4C提高了18.39%和75.27%,但其硬度降低。B4C/Al复合材料经扫描电镜和背散射仪分析后发现,无压浸渗法制备的B4C/Al复合材料中没有大尺寸的显微缺陷,组织分布比较均匀、致密;B4C以连续的骨架结构存在,而渗入的铝相也以连续基体的形式存在;单一B4C存在较多的穿晶断裂,而B4C/Al复合材料的断裂方式主要以沿晶断裂为主,这是B4C/Al复合材料断裂韧性提高的主要原因。The mechanical properties of B4C/Al composite prepared by pressureless infiltration technology were tested. The results show that the flexibility strength and the fi＇acture toughness of B4C/Al composite is greatly improved compared with those of monolithic boron carbide. The flexibility strength and fi＇acture toughness of B4C/Al composite respectively increase 18.39%,75.27%. But the hardness of B4C/Al composite decreases compared with monolithic boron carbide. The analyses of B4C/Al composite by using the fracture SEM and the back-scattering equipment show that, the microstructure of B4C/Al composite prepared by pressureless infiltration technology is more evenly distributed and compacted without large size defects ofmicrostructure. The boron carbide exists in continuous skeleton structure form, and the aluminum infiltrating into exists in continuous matrix form in the B4C/Al composite. The monolithic B4C has more transgranular fi＇acture.The main fracture way of B4C/Al composite is intercrystalline rupture, which causes the fracture toughness improving of B4C/Al composite.

关 键 词：B4C/A1复合材料 碳化硼 无压浸渗 力学性能 断裂方式 

分 类 号：TB33[一般工业技术—材料科学与工程] TQ176[化学工程—硅酸盐工业]