Investigating the microstructure and mechanical properties of tantalum sintered parts by hot pressing in a vacuum

In this study, pure tantalum powder was consolidated through hot pressing (HP) technique. This research aimed to improve the ductility and mechanical properties of tantalum. For this purpose, the effect of powder metallurgy process parameters such as sintering temperature and time on the microstructure and mechanical properties of sintered tantalum by hot pressing was investigated. Density was measured using the Archimedes method. Optical and scanning electron microscopy were used to examine the microstructure. Compression tests were conducted to evaluate the mechanical properties of the samples. The investigations showed that the porosity percentage and Porosity morphology significantly impact the mechanical properties of the tantalum studied. A 17.6% increase in density resulted in a 100% increase in compressive strength, ductility, and hardness. Increased density, decreased porosity percentage, increased effective load-bearing area, and changes in Porosity morphology, despite an increase in average grain size, led to improved ductility and mechanical properties of the sintered tantalum parts. The results also indicated that the highest hardness, compressive strength, and ductility were obtained in the sample sintered at 1600°C, with values of 345 HV, 1278 MPa, and 34%, respectively.