1Master graduated, Materials Science and Engineering Department, Faculty of Engineering, Arak University, Iran
2Assistant Professor, Materials Science and Engineering Department, Faculty of Engineering, Arak University, Iran
3PhD graduated, Materials science and engineering department, Faculty of engineering, Tarbiat Modares University, Iran
*Corresponding author: Mohammad Reza Samadi, Master graduated, Materials Science and Engineering Department, Faculty of Engineering, Arak University, Iran
Submission: January 03, 2022;Published: January 24, 2022
ISSN : 2576-8840Volume16 Issue3
The main problem in production of Tungsten Heavy Alloys (THA) is the high specific weight and melting point of the tungsten element. Nowadays, powder metallurgy plays a great role in production of these alloys. In this study, W-8Ni-2Co alloys was produced by powder metallurgy method at different condition and their microstructure and properties were investigated. For this purpose, one sample with the one-stage alloying condition was produced at 1450 ̊C sintering temperature and other samples having the same composition, were produced at 1350, 1400 and 1450 ˚C sintering temperatures in two-stage alloying condition. Scanning Electron Microscope (SEM) images showed that at two-stage alloying condition, the microstructure is more uniform and the W-W bonding reduces. In addition, it was shown that increasing the sintering temperature increases the diffusion of the bond phase (Nickel-Cobalt) and as a result, increases microstructure uniformity. The results of densitometry and micro hardness tests at the same chemical composition and sintering temperature showed that density and hardness of sample produced by two-stage alloying technique inceases16% and 31.6% respectively in comparison to the sample produced by one-stage alloying technique. Also, as the sintering temperature enhances the density and hardness increase from 15.4 to 16.832gr/cm3 and 525.2 to 541.4 Hv, respectively.
Keywords: Tungsten Heavy Alloys (THA); One stage and two-stage alloying; Sintering; Temperature; Microstructure; HardnessGet access to the full text of this article