Understanding Steel Grades

A technical guide to alloy, carbon, and tool steel profiles supplied by Praveen Steel Corporation.

Alloy Steel Versatile & Tough

Alloy steels are steels with small amounts of one or more alloying elements (other than carbon) such as manganese, silicon, nickel, titanium, copper, chromium and aluminum. These elements added to steel give it specific properties that are not found in ordinary carbon steel.

AISI 4140 / EN19

A chromium-molybdenum alloy steel with high hardenability and good fatigue strength. It is widely used for gears, bolts, and shafts in the automotive and aerospace industries.

  • Applications: Structural parts, high-tensile fasteners, hydraulic shafts.
  • Key Benefit: Excellent balance of strength and toughness.

AISI 4340 / EN24

A nickel-chromium-molybdenum alloy steel noted for its toughness and ability to develop high strength in the heat-treated condition while retaining good fatigue strength.

  • Applications: Heavy-duty axles, crankshafts, high-torque gears.
  • Key Benefit: Superior hardenability and impact resistance.

Carbon Steel Cost-Effective & Reliable

Carbon steel is the most commonly used steel in the world. It contains carbon as the primary alloying element. Depending on the carbon content, it can be mild or high-tensile.

EN8 (080M40)

An unalloyed medium carbon steel grade with reasonable tensile strength. It is usually supplied in the cold-drawn or as-rolled condition.

  • Applications: Automotive studs, basic gears, link bars, keys.
  • Key Benefit: High availability and excellent machinability.

Die & Tool Steel Extreme Hardness

Tool steels refer to a variety of carbon and alloy steels that are particularly well-suited to be made into tools. Their suitability comes from their distinctive hardness, resistance to abrasion and deformation.

D2 Steel (Cr12MoV)

A high-carbon, high-chromium cold work tool steel, heat-treatable to a high hardness. It maintains its dimensions well during heat treatment.

  • Applications: Stamping dies, industrial cutters, knurling tools.
  • Key Benefit: Exceptional wear resistance and edge-holding.

How to Select the Right Grade?

Selecting the correct steel grade depends on the mechanical stresses the component will face. For structural strength, EN8 is a great starting point. For high-wear environments, D2 is preferred. For precision components requiring high fatigue resistance, AISI 4140 is the industrial standard.