A: Generally use high-phosphorus low-silicon cast iron, boron-added cast iron, rare earth magnesium ductile iron, or a small amount of nickel-chromium-aluminum in high-quality gray cast iron to become alloy cast iron, which enhances its hardness and wear resistance, and its surface hardness can reach 190. -250HB, overhaul mileage can reach 250,000-300,000 kilometers.
