|About this Abstract
||MS&T23: Materials Science & Technology
||Metal Powder Synthesis and Processing: Fundamental Aspects and Modeling
||Resolving the Sintering Conundrum of Tungsten Alloys
||Lin Zhang, Zhongyou Que, Xingyu Li, Xuanhui Qu
|On-Site Speaker (Planned)
Ultrafine-grained tungsten alloys have important applications in aerospace, semiconductor, high-temperature equipment and nuclear energy because of their outstanding high-temperature mechanical properties. Powder metallurgy, with excellent controlled chemistry and near-net shape manufacturing, is optimal method for producing tungsten alloys. However, the high temperature of powder metallurgy makes the grain size grow rapidly during the densification process. How to maintain fine grain structure and achieve complete densification is still a sintering conundrum. This paper reports the successful production of dense tungsten and tungsten-rhenium alloys with average grain size of ~300 nm and uniform microstructure by pressureless two-step sintering. Further, the densification kinetics and grain growth were studied respectively, and the advantages of pressureless two-step sintering to produce tungsten alloys were clarified. Our works shows the scientific understanding and technological practices of producing ultrafine-grained tungsten alloy by pressureless two-step sintering.
Keywords: Tungsten alloys; Two-step sintering; Densification; Grain growth; Ultrafine-grained materials.