抄録
The sinterability, mechanical properties, and corrosion resistance to zinc-5.3mass%Al molten alloy were investigated for WC-17mass%Co cemented carbides in the phase regions of WC+γ+FC, WC+γ, WC+γ+η, WC+η, WC+η+θ and η+θ+W, i.e., down to extremely low carbon content.
The results obtained were as follows: (1)The sinterability became inferior with decreasing carbon content; the alloys in the WC+η+θ and η+θ+W regions were not fully densified by sintering even at 1773K for 3.6ks. (2)The hardness(Hv) of the alloy increased with decreasing carbon content from 1150 in the WC+γ region to the maximum value of 1450 in the WC+η region, and then decreased to 1000-970 in WC+η+θ and η+θ+W regions. (3)The flexural strength showed about 1.7GPa even in WC+γ+η region, although it was lower than 3.8GPa in the WC+γ region. (4)All kinds of alloys did not react with the molten zinc alloy at 773K (for 21.6ks).The alloy containing γ phase, however, considerably reacted at 873K above the peritectic temperature of γ1 (Co-Zn intermediate phase) /liquid zinc (839K), while the alloy in the WC+η+θ and η+θ+W region did not reacted.
