astm4140 is a material used to manufacture forgings that require higher strength than 35CrMo steel and a larger quenched and tempered section
Scope of application
High strength, hardenability, good toughness, small deformation during quenching, high creep strength and lasting strength at high temperature. It is used to manufacture forgings that require higher strength and larger quenched and tempered section than 35CrMo steel, such as large gears for locomotive traction, supercharger transmission gears, rear axles, connecting rods and spring clamps that are heavily loaded. It can also be used Drill pipe joints and fishing tools for oil deep wells below 2000m.
ASTM 4140 Steel is a Alloy Structural Steel belong to ASTM A29/A29M Steel Grade standard.
A519 Gr.4140 standards applicated in the seamless alloy pipe.
Chromoly is specified by the “SAE” Society of Automotive Engineers. the Alloy elements of 4140 are chromium and molybdenum, this is why its often called chromoly or cromo. Chromoly has an excellent strength to weight ratio, is easily welded and are considerably stronger and harder than standard 1020 mild seamed and DOM tube steels.
The numbers 4140 defines the chemical composition of the steel.
Its performance is much higher than the average of seamless steel tubes, because the steel contains Cr more inside, alloy seamless pipe, its high temperature, low temperature resistance, corrosion resistance is smaller than other seamless.
Especially, it need to do the quenched & tempered and has a high technical requirements. so alloy tube in the petroleum, chemical, electric power, boiler and other industries use more widely.
4140 chromoly tubing began its first use in the aircraft industry. Race chassis builders began using the tubing for its strength to weight ratio.
4140 tubing is used for anything from bicycle frames, AK-47 receivers, tubular chasis, suspension parts, aircraft parts and air frames etc… Ive used cromo for suspension components, cages / tube chassis and machined parts.