Determination of the DBTT of nanoscale ZrC doped W alloys through amplitude-dependent internal friction technique

In this paper, 1 mm thick W-0.5 wt%ZrC alloy plates were prepared by mechanical milling, hot pressing sintering and multistep hot and cold rolling. A newly developed testing technique based on the amplitude-dependent internal friction (ADIF) was used to determine the ductile-to-brittle transition temperature (DBTT) of this W-0.5 wt%ZrC alloy. The DBTT obtained by ADIF technique is in the range of 50-80 degrees C, which is in consistence with the tensile tests. Qualitative relationship between the critical strain amplitude in ADIF and the yield stress in tensile test was also found. The ADIF technique was confirmed to be an available method to determine the DBTT of the materials. Microstructure analysis indicated that the relative low DBTT and the high strength of the W-0.5 wt%ZrC alloy plates were resulted from the multistep hot and cold rolling and nanoscale particle pinning effects.