Synthesis and characterization of zirconium alloy by spark plasma sintering (SPS)

Zirconium alloys are widely applied as nuclear fuel cladding materials due to its excellent neutron transparency. However, a major challenge in developing this material is the strong affinity of Zirconium to Hydrogen, Oxygen, and Nitrogen. Therefore, precise techniques and processing parameters are essential for fabricating this alloy. In this study, Zr-alloy according to the Zircaloy-4 composition has been synthesized using a Spark Plasma Sintering (SPS). For this purpose, we used the commercially available Zr powder with alloying materials such as Sn, Cr, and Fe. The powders were mixed and wet milled using a shaker mill for 30 minutes and dried to evaporate a process control agent. The mixture powder was then consolidated using a SPS method under vacuum conditions at a sintering temperature of 900 °C with a heating rate of 50 °C/min and a holding time of 5 min. XRD and SEM-EDS were applied to investigate the phase composition, microstructure, and elemental analysis of the powder and sintered alloy. In addition, the density and hardness of the sintered Zr-alloy were also evaluated. The results show that the high density of Zr-alloy (6.59 g/cm³) with a hardness of about 566.05 HV is successfully synthesized using a SPS technique. The alloy comprises α-Zr and ZrH2 with fractions of 88.1% and 11.9%, respectively. A comprehensive analysis of the results will be presented and discussed in the forthcoming paper.