Strengthening and Toughening Effect on Tungsten Subjected to Multiple ECAP
This paper presents the research results of the grain refining effect on the ductile-to- brittle transition temperature (DBTT) of commercial purity tungsten. The as-received tungsten was subjected to eight passes of equal-channel angular pressing (ECAP) at decreasing temperatures from 1300 to 1150 °C. According to optical and TEM microscopy the average grain size was refined considerably from ~80 μm to ~1 μm. The mechanical tensile tests, carried out at various temperatures for the tungsten samples, showed that DBTT decreased approximately 80 °C as a result of microstructure refinement by ECAP, at the same time the strength also increased 50-100 % by grain refinement. SEM observation of the fractures confirmed the mechanical testing results.
Jing Tao Wang, Roberto B. Figueiredo and Terence G. Langdon
H. Yuan et al., "Strengthening and Toughening Effect on Tungsten Subjected to Multiple ECAP", Materials Science Forum, Vols. 667-669, pp. 701-706, 2011