Sintering Behavior of Al/B4C-AlB12-Al2O3 Nanostructure Composite Synthesized by In Situ Processing Method

The aim of this article is to study the effect of time and temperature of sintering on the properties and microstructure of Al/B4C-AlB12-Al2O3 nanocomposite synthesized via in situ processing method. In this method, a mixture of Al-B2O3-C, as starting materials, was activated and reacted in a planetary ball mill under Argon atmosphere. The phase analysis, morphology, and particles size were studied by x-ray diffraction and scanning electron microscopy methods. The composite powders were compressed with uniaxial cold press and then were sintered at different temperatures (470-600 °C) for various times (30-90 min). The density, hardness, and compressive strength of sintered samples were investigated. The results revealed that by increasing the sintering temperature and sintering time, both hardness and compaction strength of nanocomposite reach to maximum at 560 °C. The results showed that the sample sintered at 560 °C for 90 min had highest sintered density (≈2590 kg/m3) and highest hardness value of ~88 BHN with compaction strength of ~313 MPa. Nanosize and homogeneous distribution of in situ formed ceramic particles were observed in the synthesized composite.