2.2 low alloy white cast iron
The main eutectic carbides in low alloy white cast iron are M3C type (HV most in 1100~1400). The distribution of eutectic carbide is reticulate. And the toughness is low. Most of the eutectic carbides can only be used in the field of low stress abrasive wear. In conclusion the common application of low alloy white cast iron in Wear-resisting pipe are:
- A. Cr- Mo – Cu low alloy white cast iron
Because the production of Ni in China is less. And also the price is more expensive. As a result the Ni – Hard cast iron application is very slow. And also the requirement of ball and lining is large quantity and wide application area. Therefore Cr – Mo – Cu white cast iron has more application instead of Ni -Hard cast iron. The cast state hardness of the cast iron is about 50HRC. After hardening heat treatment, hardness can be HRC57 ~ 62 and αk can almost reach 7J / cm2. The main components were probably 2.4% to 3.2%C, 0.8 to 1.3%Si, 0.8 to 3.0%Mn, 0.2 to 0.5%Mo, 0.2 to 0.5%Cu.
- B. Manganese molybdenum and manganese tungsten low alloy white cast iron
On the basis of the composition of medium manganese, added 0.8 to 1.5%Mo, or 2.5% ~ 3.5%W. And the as-cast HRC was 53~58. αk was 5 to 6J / cm2. Most of them were for the production of vulnerable parts. Such as impurities pump and shot blasting machine. And also some used for grinding ball.