Alloy steel 4140 is a versatile low-alloy steel that contains chromium, molybdenum, and manganese. It has a high tensile strength, good fatigue strength, and excellent toughness, making it ideal for use in applications that require high strength and resistance to wear and impact. Additionally, it has good corrosion resistance and can be heat treated to achieve a wide range of mechanical properties. It is often referred to as "chrome-moly" steel.

The normal use cases for alloy steel 4140 include the manufacturing of automotive components, aerospace structures, industrial equipment, and machinery. It is commonly used in the production of axles, shafts, gears, and tooling. Its strength and durability make it a popular choice for heavy-duty applications that require high performance and reliability.

At FastMetals.com, alloy steel 4140 is available in various forms, including round bar and flat/rectangle bar. The round bar is available in diameters ranging from 1/4 inch to 3 inches and can be cut to length. The flat bar is available in thicknesses ranging from 1/4 inch to 1 inch and from 1 inch to 3 inches wide and can also be cut to length. All forms of alloy steel 4140 are available in custom sizes to meet specific application requirements.

CHEMISTRY:
  • Carbon .38/.43
  • Manganese .75/1.00
  • Phosphorus .035 max
  • Sulfur .040 max
  • Silicon .15/.35
  • Chrome .80/1.10
  • Molybdenum .15/.25
MECHANICAL PROPERTIES:
  • Annealed Cold Finish BHN 241 max