40Cr China China GB standard steel, 40Cr steel is the most widely used mechanical manufacturing of steel. After quenching with good mechanical properties, good low temperature impact toughness and notch sensitivity. Good hardenability of steel, when quenched in water quenching to Ф28 ~ 60mm, when oil quenching hardenability to Ф15 ~ 40mm. In addition to quenching of this steel is also suitable for external cyanide and high-frequency quenching treatment. Cutting is better, when the hardness HB174 ~ 229, the relative machinability of 60%. The production of steel suitable for medium-sized plastic molds.

According to the standard GB / T 3077-1999

Corresponding foreign standards: JIS G4053

ASTM A29 /

ISO 683-18:1996

Feature
Modulation of carbon steel, cold heading die steel. The steel price is moderate, easily processed, after appropriate heat treatment after the availability of a certain toughness, ductility and wear resistance. Normalizing the ball of the organization can promote and improve the hardness of less than 160HBS rough cutting. Temperature of 550 ~ 570 ℃ in the tempering, the steel has the best mechanical properties. Hardenability of the steel is higher than 45 steel, suitable for high-frequency hardening, flame hardening and other surface hardening treatment.

Use
This steel quenched after for the manufacture of medium load and medium speed to withstand the mechanical parts work, such as automotive steering knuckle, on the machine after the axle and gear, shaft, worm, spline shaft, the top cover, etc.; by quenching and medium-temperature tempering for the manufacture of high load, the impact of work and medium speed parts such as gears, shaft, oil pump rotor, slide, rings, etc.; after quenching and tempering for the manufacture of heavy duty, low impact and wear resistance, cross-sectional thickness of 25mm on the following physical components, such as worm, spindle shaft, ring, etc.; after quenching and after quenching for the manufacture of high-frequency surface has a high surface hardness and wear resistance no significant impact on the parts such as gears, sleeves, shafts, spindles, crankshafts, spindles, pins, connecting rods, screws, nuts, intake valve and so on. In addition, the manufacture of steel and suitable for carbonitriding treatment of a variety of transmission parts, such as large diameter and low-temperature toughness, good gear and shaft.

[Supplier] state and hardness

     Annealed, the hardness ≤ 207HBS.