Black cast iron has better casting properties than carbon steel. The ability of liquid alloys to fill dies and obtain complete shapes and clear contours is called the filling ability of liquid alloys. Inadequate filling capacity will lead to inadequate casting or cold insulation defects in castings. The so-called bottom filling means that the shape of the casting is incomplete; cold separation means that a joint is formed somewhere in the casting due to the melting of two or more metal streams. The main factors affecting filling capacity are alloy fluidity, casting conditions, filling conditions of dies and casting structure.


If low carbon steel has better forging performance than high carbon steel, it is because of low carbon content, strain stress is not easy to brittle in forging process, internal stress of cast iron is very large, and there are many dislocation impurities, it is easy to brittle, not because it has strong casting ability. It can't be forged. Of course, nodular cast iron can be cast, but the cost is worth considering. Carbon steel is not cast, not cast. It is absolutely obtained by casting, but forging will get better performance. We usually forge low carbon steel and cast high carbon steel, which is more suitable for medium carbon steel in locomotive processing.