4140 Alloy Round Bar
4140 is a chromium and molybdenum alloy steel that has an excellent weight to strength ratio. It is considerably stronger than standard steel. Although it is chromium steel and often referred to as “chromoly steel” it does not contain as much chromium as stainless steel. Therefore the corrosion resistant is improved compared to standard steel but not to the same degree as stainless steels. The purpose of the molybdenum is to add uniformity of hardness and strength to this alloy. 4140 responds readily to heat treatment and is relatively easy to machine in the heat treated condition. It has a tensile strength of 150,000 psi, yield strength of 130,000 psi and approximately 35-45% elongation. This metal is typically used for bolts couplings, axle shafts, piston rods, tractor arms, clutch and flywheel components, sprockets, etc.