4150 AISI 4150 SAE 4150 Alloy Steel - Equivalent Steel - Steel Overview - 1010|1015|1020|1025|1045|1018|1117|1035|1040|1050|1215|4140|4150

4140/4150 - Widely used general purpose alloys, low in cost. A broad range of strength and toughness is attainable through variations in heat treatment. Used for forging, tubing and fittings.AISI 4150 is notable for increased hardenability with a small tradeoff in machinability. Best strength and hardness appears in preheat-treated condition. Tailoring carbon content to bar size allows uniform physical attributes to be maintained across a variety of sizes. These are oil-hardening steel of relatively high hardenability. Their chromium content provides good hardness penetration, and the molybdenum imparts uniformity of hardness and high strength.

These grades are especially suitable for forging because they have self-scaling characteristics. They respond readily to heat treatment and are comparatively easy to machine in the heat treated condition. They resist creep in temperature up to 1000°F and maintain their properties even after long exposure at these relatively high working temperatures. With a combination of such highly desirable properties as good strength and wear resistance, excellent toughness coupled with good ductility, and the ability to resist stress at elevated temperatures, it is widely used and highly successful alloy steel.

This material is also available as leaded steel. The addition of lead improves machinability without sacrificing other desirable properties, with the exception that the use of this material is not recommended for applications over 400°F, since at elevated temperature ductility is low.

The following specifications are generally applicable for 4140/42 Heat Treated Rounds: ASTM A 193, Grade B7; ASTM A 434, Grades BC and BD. A special analysis of alloy steel which is heat treated by oil-quenching and tempering to develop a balance of mechanical properties. Has every requisite for brake die service-high wear-resistance, adequate toughness, high resistance to impact, and good machinability. In addition, the bars are stress-relieved before the final gag straightening, to insure a minimum of residual stresses.

To obtain values for this property, specimens were taken from large and small sections, machined oversize, heat treated and finished by grinding to 0.505 in. diameter x 0.750 in. long. The specimens were checked for hardness and were then compressed between hardened steel plates. the specimens tested showed a hardness of 269 Brinell and indicated that both small and large sections developed compressive strength in excess of 100,000 psi, adequate compressive strength to meet the maximum demand of heavy duty brake-die service.