In situ WAl_(12) particle-reinforced Al matrix composites synthesized by combining mechanical alloying and vacuum hot pressing technology

摘要

In this work, mechanical alloying (MA) and hot-pressed (HP) sintering have been employed to fabricate a series of Al-based metal matrix composites (MMCs) reinforced with WAl_(12) particles. In particular, mechanical alloying method was used to fabricate W_(14)Al_(86) new alloy. WAl_(12) compound is in situ generated through Al and W_(14)Al_(86) powder blend in order to enhance the mechanical properties. By X-ray diffraction (XRD) and scanning electron microscopy (SEM), it was found that WAl_(12) intermetallic particles were in situ formed in the MMC during hot-pressing AI-W14AI86 system. Density measurements using Archimedes' method and microhardness test were carried out for all the samples. By increasing the weight percentage of WAl_(12), both density and microhardness increased significantly. The tensile strength of samples was up to 487 MPa at room temperature, and up to 248 MPa at 200 °C.