Abstract
New chromium base hard-facing alloys are Cr-Ni-X system alloys containing more over 50% by weight of chromium, where X represents small amounts of molybdenium, boron, and silicon.
In this paper, these alloys(717, 737) were investigated in hardness, impact value, wear resistance, corrosion resistance, and weldability for PTA process, compared with those of conventional cobalt base alloys(CoCr-A, CoCr-B) and nickel base alloy(NiCr-B). The results were summurized as follows:
1) These alloys had enough hardness and impact value as hard-facing alloys.
2) Wear resistance of these alloys were better than that of conventional cobalt base alloys and nickel base alloy.
3) Corrosion resistance of these alloys were superior to conventional cobalt base alloys and nickel base alloy. In particular weight losses in 5%H2SO4. 65%HNO3, and 90%Na2SO4+10%NaCl molten ash were negligible.
4) These alloys had good weldability for PTA process in the same manner as convensional cobalt base alloys.
