抄録
The preparation for WC-FeAl hard metal was investigated using FeAl2 (Fe-50 mass% Al) powder and pure-Fe powder as the materials of binder phase. Powder mixtures of WC, FeAl2 and pure-Fe which compositions were WC-25 vol% (Fe-X at% Al), (X = 0, 10, 20, 30, 40, 50, 67) were compacted to test-pieces and sintered in vacuum of 10−3 Pa order at 1050 °C,1250 °C and 1450 °C for 1 hr. By the analyses of SEM, XRD and WDS, the following results obtaind; (1) FeAl2 powder reacted with pure-Fe powder to FeAl alloy below melting point (1170 °C) of FeAl2. (2) On the microstructures of the WC-25 vol% (Fe-0, 10 and 20 at% Al) compacts sintered at 1450 °C, η-phase of W-Fe-Al-C was observed besides WC and FeAl alloy.
Powder mixtures of (1) WC, FeAl2 and pure-Fe, (2) WC and FeAl (Fe-40 at% Al) alloy which composition was WC-25 vol% (Fe-40 at% Al) were wet-milled for 48 h. Sintered compacts were prepared using the milled powders. Transverse rupture strength and Vickers hardness of both compacts were almost equal level of 1.6 GPa and 1300 HV respectively when they were sintered at 1450 °C and 1475 °C. Both compacts had fine and homogeneous structures.
