What is the different between 42CrMo steel And 42CrMo4 steel

42CrMo steel is a kind of medium-carbon alloy structural steel with good comprehensive performance and good hardenability. It is often used to manufacture gear, connecting rod, high strength bolt and other important parts in machining process. The engineers often saw a material of 42CrMo4 steel mentioned in the European standard drawings.

They come from different standards from different counties. 42CrMo steel is the material in Chinese standard GB/T 3077, specification of alloy structural steel. The material of 42CrMo4 steel belong to EN 10083 series, hardened and tempered steel.

Different delivery condition. 42CrMo steel is usually delivered in the condition of hot rolled and hot forging. If the customer needs the heat treatment condition (annealing, normal goods, high temperature tempering), it shall be specified in the contract. For EN10083 42CrMo4 steel, there are five delivery conditions for choice: no heat treatment, heat treatment, softening annealing, quenching and high temperature tempering and other heat treatment.