抄録
WC-0.40mass%VN-0.44mass%Cr3C2-8.0mass%Co alloy with different amount of carbon content using commercially available 0.4 micron WC powders were prepared by sintering and HIPing. In these alloys trace amount of V-rich phase were observed by EPMA analysis.
Quantification of V-rich phases was performed as follows. (1) The location of V-rich phase was determined by EPMA. (2) Determination of the same V-rich phase was performed by FE-SEM. (3) Cutting off the portion containing the V-rich phase and making thin film was done by FIB. (4) Determination of the size of V-rich phase was carried out by FE-TEM observation. (5) The threshold value was set by coincidation of the size by FE-TEM with peak width of EPMA line analysis. (6) EPMA V mapping image was binarized by the threshold value. (7) Area % was obtained by image analysis of binarized image. (8) Random 20 fields were analyzed by the same method mentioned above and average value was obtained.
The amount of V-rich phase in middle carbon alloy was 0.008 area% and the amount of V-rich phase increased with increasing carbon content from 0.001 to 0.051 area%.
