Effects of heat treatment on phase contents and mechanical properties ofinfiltrated B4C/2024Al composites
(1. State Key laboratory of Powder Metallurgy, Powder Metallurgy Research Institute,
Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China)
Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China)
Abstract: The B4C/2024Al composites were successfully produced by pressureless infiltration method, and the effects of heat treatment on phase content and mechanical properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and mechanical properties testing. The results show that phases of B4C/2024Al composites include B4C, Al, Al3BC, AlB2 and Al2Cu. The phase species remain unchanged; however, the phase content of the composites changes significantly after heat treatment at the temperature of 660, 700, 800 or 900 °C for 12, 24 or 36 h. It is found that the heat treatment results in not only considerable enhancement in hardness, but also reduction in bending strength of the composites. Heat treatment at 800 °C for 36 h does best to hardness of the composites, while at 700 °C for 36 h it is the most beneficial to their comprehensive mechanical properties.
Key words: B4C/2024Al composites; heat treatment; pressureless infiltration; hardness; bending strength