Low-temperature formation of ternary carbide Fe3M3C (M = Mo, W) assisted by mechanical activation

Ternary carbides, Fe3Mo3C, Fe3W3C and Fe6W6C formed from the powder mixture s of Fe/M/C = 1:1:1 (M = Mo, W), which were ground for 3 h in a planetary b all mill and subsequently heated at a temperature of 700-800 degreesC. The amount of these carbides increased with an increase in the heating temperat ure. In contrast, when the samples, which were ground for 0-1 h, were heate d to 700-1100 degreesC, Mo,C and WC formed exclusively. From the results co ncerning the effects of mixing ratio, grinding time and heating temperature of the Fe/M/C (M = Mo, W) samples on the formation of ternary carbides, it was found that the formation of Fe3Mo3C, Fe3W3C and Fe6W6C strongly depend s on the mixing homogeneity, the intimate contact and the activated state o f the Fe, Mo (or W) and C grains, finely ground by ball milling. (C) 2001 E lsevier Science B.V. All rights reserved.