Cast iron commonly used sand casting production, its fracture visible gray grain, so also known as gray cast iron.

Gray cast iron has a good casting and cutting performance, high wear resistance, vibration reduction, and low notch sensitivity. Because of the high carbon content and the thick structure, its tensile strength is not very high, relatively brittle, but very good compression resistance.

The gray cast iron brand is indicated by “HT after tensile strength level.” Gray cast iron pieces brand has six: HT100, HT150, HT200, HT250, HT300 and HT350, they all have certain tensile strength, because of good wear resistance, resistance to vibration, easy to machining, maintain good accuracy after aging treatment or heat treatment, mostly as mechanical parts, such as machine tool base, cast iron plate, hydraulic press piston platform, plastic crusher, pulley, bearing, reducer shell, etc.