8620 and 8620H English: in compliance with ASTM A29/A29M – 16, DIN 1.1141 and JIS S18C, it is distinguished by its versatility. Its chemical composition, which includes percentages of carbon, chromium, molybdenum and nickel, is supplied in annealed state with an approximate hardness of 150 HBN (~80 HRB) due to cold drawing, this steel has a tensile strength of 536 MPa (77,800 lb/in²), yield strength of 357 MPa (55,900 lb/in²), elongation of 31%, and hardness of approximately 150 HBN (~80 HRB) at room temperature.
Features 8620 and 8620H
Among its outstanding characteristics are its good hot forgeability and weldability, it has acceptable machinability, 61% machinability compared to 1112 steel (taken as a 100% reference), with cementation treatment, it is suggested in manufacturing of gears, crowns, worms, bushings, bearing races, and more, especially in environments where resistance and surface hardness and a soft core are required, to counteract wear due to dynamic metal-metal contact.
To increase its wear resistance, carburizing or carburizing treatment, surface carbunitriding, and tempering at 150 °C for one hour is recommended, regardless of the previous process, offering an option to maintain toughness without a significant loss of hardness, while a Tempering at 260 °C can be considered to increase toughness when required.
