Hard steel, high manganese steel, chromium steel, alloy cast iron, rubber and magnetic lining board can be used as the materials for wear-resistant castings. High manganese steel has enough impact toughness, and when it is subjected to certain impact, its surface is cold hardened and becomes hard and wear-resistant. Therefore, high manganese steel is widely used to make wear-resistant casting lining plates.
Now let's talk about the casting process design of high manganese steel.
Manganese steel is characterized by large solidification shrinkage and poor heat dissipation. According to this, the casting shrinkage rate is 2.5%-2.7% in process design. The larger the casting is, the higher the upper limit should be.
The yielding of sand and sand core must be better. The gating system is open. A plurality of dispersed sprues are introduced from the thin wall of the casting and are in a flat and wide horn shape, and the cross-sectional area near the casting is larger than the cross-sectional area associated with the runner, so that molten metal is injected into the casting mold quickly and stably, and excessive temperature difference in the whole casting mold is prevented.
Pour as quickly as possible at low temperature. Once solidified, loosen the sand box in time. Smart designers are always good at using chilled iron, including inner chilled iron and outer chilled iron. It not only refines primary crystallization, eliminates shrinkage cavity and porosity, but also improves process yield. Of course, appropriate dosage and specifications should be considered.