Surface carburizing during hot isostatic pressing

The product preparation and surface carburizing of Ti-6Al-4V alloy are usually carried out separately, which leads to a low production efficiency and high processing costs. In this study, hot isostatic pressing (HIP) was proposed to complete the product preparation and surface carburizing of Ti-6Al-4V alloy simultaneously. Ti-6Al-4V powder compact with carburized layer is successfully fabricated using this method. X-ray diffraction and Energy dispersive spectrometer analyses illustrate the carburized layer is mainly composed of C, TiC and Ti. Scanning electron microscope shows a uniform TiC layer and an obvious diffusion region in the carburized layer and the total thickness is about 104 mu m. The Ti-6Al-4V region is composed of equiaxed grains and typical lathlike structures. The Vickers hardness of the carburized layer especially the TiC layer is higher than the Ti-6Al-4V region. These results indicate that HIP is a promising process for product preparation and surface carburizing of Ti-6Al-4V alloy.