Industry and Characteristics of Cast Iron Castings

1. Characteristics of the bed: ⑴ Naimoxing and xiao have good vibration resistance.

. ⑵ Good process performance. Due to its high carbon content and eutectic composition, gray cast iron has a relatively low melting point, good flowability, and low shrinkage rate, making it suitable for casting complex or thin-walled castings. In addition, due to the tendency of graphite to form chips during cutting, the machinability of gray cast iron is superior to that of steel. 2、 The relationship between hardness and tensile strength: There is a corresponding relationship between the hardness and tensile strength of gray cast iron, and its empirical formula is: 1. HB=RH (Fei 00+0 4380b) (B1) when O ≥ 196N/mm ㎡ 2. 2. HB=RH (44+O 7240c) (B2) when 0 ≥ 796N/mm ㎡. The relative hardness (RH) value in the formula is mainly determined by the raw material, melting process, treatment process, and cooling rate of the casting. 3、 Advantages of using resin sand casting machine bed castings: 1. In the production of solid casting, polystyrene foam mold is used for self hardening sand molding with epoxy resin. When the metal liquid is poured into the mold, the foam plastic pattern will be vaporized under the action of the high-temperature metal liquid, and will disappear after burning. The metal liquid replaces the position occupied by the original foam plastic, and will be cooled and solidified into a full mold casting with the same shape as the pattern. Relatively speaking, lost foam casting has great advantages over traditional sand molds for producing single or small batches of automotive coverings, machine tool beds, and other large molds. It not only saves expensive wood mold costs, but also is easy to operate, shortens production cycles, improves production efficiency, and has advantages such as small size, small machining allowance, and good surface quality. Types of annealing for casting heat treatment: Common annealing processes include recrystallization annealing, stress relief annealing, spheroidization annealing, annealing, etc. The purpose of annealing is mainly to reduce the hardness of metal materials, improve plasticity, facilitate cutting or pressure processing, reduce residual stress, and improve microstructure and cost

The resin sand mold has good rigidity, and in the early stage of casting, the sand mold can effectively utilize the graphitization expansion during the solidification process of cast iron to eliminate shrinkage and porosity defects, achieving less riser and no riser casting of gray cast iron and ductile iron parts