3. Results and discussion
3.1. Composition and microstructures of the sintered hard alloys
The XRD patterns of the WC–Fe hard alloys with 0 and 1.5 wt.%
Cu sintered at 1300 C are shown in Fig. 1. By XRD, only WC hard
phase and Fe binder metal phase were identified in each sample.
The XRD patterns of other samples (with 0.5 wt.%, 1.0 wt.%,
2.0 wt.% and 2.5 wt.% Cu sintered at 1300 C and with 0, 0.5 wt.%,
1.0 wt.%, 1.5 wt.%, 2.0 wt.% and 2.5 wt.% Cu sintered at 1250 and
1350 C) are similar with the shown patterns. Fig. 2 shows the
mapping of elements distribution of WC–Fe–1.5 wt.% Cu hard alloy
sintered at 1300 C. It shows that Cu distributed in Fe. From Figs. 1
and 2, it can be concluded that Cu dissolved in Fe and the binder
phase is Fe–Cu alloy.