Solid state recycling of Vanadis®8 steel scraps using powder metallurgy

Vanadis®8 is a high-value tool steel, that undergoes gas atomization and hot isostatic pressing during production , resulting in costly waste. Repurposing this waste material through powder metallurgy (PM) offers a cost-effective solution. This study explores the PM process applied to Vanadis®8 steel scraps, involving high energy ball milling, uniaxial pressing, and sintering. The final product and the as-received steel underwent heat treatments, including quenching and tempering. Microstructural evaluation employed X-ray diffraction and scanning electron microscopy, while physical evaluation entailed Archimedes density measurements. Mechanical analysis was carried out through microhardness and compression strength tests. Results revealed that optimal milling conditions were achieved at 30 hours with 400 rpm (s^-1). Vanadis®8 steel produced through PM attained 85% densification compared to the as-received material (6.31 g/cm³ ). MC-type carbides were present in all evaluated conditions. Heat treatments improved mechanical values for all conditions, suggesting that PM-produced Vanadis®8 steel, subjected to quenching and tempering, presents a viable reuse option. (author)