ABSTRACT
The cost-efficient Ti-1Al-8V-5Fe-xSi (denoted Ti-185-xSi hereafter, x = 0, 0.15, 0.3, 0.45, 0.6, 0.75) alloys are synthesized by cold compaction and sintering powder metallurgy (PM) technology using TiH2 and high-pure FeV80 powders. The sintering densification, microstructural evolutions and mechanical behavior of Ti-185-xSi alloys sintered at 1350°C are investigated. The results show that the Si element is favorable to enhance the sintered density of Ti-185 alloys, which should be limited to ≤0.3%. The amount and average size of precipitate Ti5Si3 increase in the Ti-185 alloys with increasing Si content. Meanwhile, the Rockwell hardness of Ti-185 alloy also displays an increasing tendency, suggesting the Si element can improve the hardness of Ti-185. The Ti-185–0.15Si alloy possesses a better comprehensive mechanical property of strength (937 ± 8 MPa) and elongation (3.5%). The high-performance Ti-185 alloy is successfully prepared using low-cost FeV80 master alloy with slight Si impurity instead of costly V.
Acknowledgments
The authors thank Dr. Xing Guo for some characterization analysis and testing the mechanical properties, Dr. Qiangguo Li for technical help and fructuous discussions. This work was mostly supported by Professor Yungui Chen from Sichuan University in China.