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HR 4150 steel bar is a higher carbon steel consisting of chromium, manganese, and molybdenum. However, this steel is considered a low carbon steel because its percentage of metals is low in comparison to its main iron component. 4150 HR steel is known for its increased hardenability and mechanical properties. The machinability of 4150 steel bar is better in the annealed form. Eaton Steel Bar Company stocks many diameters of 4150 hot rolled steel to meet the markets demand. We also supply 4150 steel bar to various industries like aerospace, automotive, construction, and tooling.

4150 hot-rolled-steel-bar

4150 HR Steel Bar Applications

Typical applications for this grade include shafts, couplings, valves, axles, bolts, drilling parts, and aerospace parts.

Shapes and Sizes

Eaton Steel Bar Company supplies 4150 steel bar in a variety of sizes ranging from 7/8”-15”. The shapes available for this grade include:

  • Rounds

Standard "4150 Grade" Chemical Composition

Carbon 0.48-0.53
Manganese 0.75-1.00
Phosphorus (max) 0.035
Sulfur (max) 0.040
Silicon 0.15-0.35
Chromium 0.80-1.10
Molybdenum 0.15-0.25


Estimated Mechanical Property Ranges for "Grade 4150"

Tensile strength (psi) 100,000 - 110,000
Yield strength (psi) 70,000 - 80,000
Elongation in 2” (%) 15 - 25
Reduction of area (%) 30 - 40
Brinell Hardness (BHN) 210 - 240