4130 heat treat is an aircraft quality chromium-molybdenum alloy steel primarily melted in an electric air furnace. After melt, this low alloy steel has been hardened and tempered per specification AMS-6346. This hardening process produces a minimum tensile of 125 ksi and a hardness as high as 35 HRC 4130, also known as Chromoly Steel, is often used in the construction of commercial aircrafts, military aircrafts, ground support systems, race cars, off road vehicles, hydraulic tools, and machine tool applications. (UNS G41300)
