What are the differences between ZG235-450 and ZG270-500?

ZG cast steel refers to steel with a yield strength of 235/270 and a tensile strength of 450/500. I think the main difference among these types lies in their carbon content. Below is some information about ZG270-500: Key characteristics of ZG 270-500: It is a medium-carbon cast steel with certain toughness and plasticity; it possesses high strength and hardness, good machinability, fair weldability, and better casting properties compared to low-carbon steel. Applications of ZG 270-500: It is widely used in the manufacture of flywheels, vehicle couplings, hydraulic press cylinders, frames, steam hammer cylinders, bearing housings, connecting rods, casings, and crankshafts. Mechanical properties of ZG 270-500: Yield point ós or yield strength ó0.2/MPa ≥270; Tensile strengthób/MPa ≥500; Elongation δ (%) ≥18; Reduction of area Ψ (%) ≥25 as specified in the contract; Impact absorption energy AK/J ≥22 as specified in the contract; Impact toughness aK/(J/cm2) ≥35. Chemical composition of ZG 270-500: Maximum content of elements (by mass percentage) (%) – C: 0.40; Si: 0.50; Mn: 0.90; S: 0.04; P: 0.04. Residual elements: The total amount of residual elements shall not exceed 1.00%; if no requirement is specified by the customer, analysis of residual elements is not necessary. 　　Ni 0.30 　　Cr 0.35 　　Cu 0.30 　　Mo 0.20 　　V 0.05

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