B4C-Al中子吸收材料拉伸性能及断裂机理

为评价粉末冶金法制备的B₄C-Al中子吸收材料的力学性能，采用静态拉伸的试验方法研究板材的室温及高温拉伸性能，并运用扫描电镜进行断口形貌观察，对复合材料的断裂机理进行讨论。研究表明：室温下，B₄C质量分数为30%的B₄C-Al复合板材的屈服强度为200 MPa，抗拉强度为250 MPa，断后伸长率为2.5%；在实验范围内，随着温度的升高，材料的抗拉强度和屈服强度下降，并趋于一致，材料的断后伸长率增加并达到最大值。复合材料的断裂宏观表现为脆性断裂，断裂是由基体内微孔隙成核、聚集和基体与增强相的界面脱粘断裂的共同作用造成的。

Tensile Property and Fracture Mechanism of B4C-Al Neutron Absorber Material

To get the mechanical properties of B₄C-Al plate made by powder metallurgy, B₄C-Al plate was tested by static tension, fracture appearance was investigated by scanning electron microscope (SEM), and the mechanism of fracture was discussed. The results show that at room temperature the yield strength, the tensile strength and elongation of the composite with 30% B₄C are 200 MPa, 250 MPa and 2.5%, respectively. When the temperature of tensile test is elevated, the tensile strength and the yield strength of composites decrease and approach to one value, and the elongation increases and reaches maximum value. Fracture behaves in macro-scope as brittle fracture and is caused by the appearance and accumulation of hole in matrix and the separation of reinforced particles and matrix.