SCM440|4140|42CrMo Steel Plate

4140 steel plate is a chromium-molybdenum alloy structural steel known for its high strength, toughness, good wear resistance, and wide use in automotive, oil & gas, and machinery industries.

What is 4140 steel Plate?

4140 steel is a chromium-molybdenum alloy steel known for its excellent toughness, high fatigue strength, and good wear resistance. It typically has a tensile strength of 655–880 MPa, yield strength of 415–655 MPa, elongation of 25–30%, and reduction of area of 50–60%. In the quenched and tempered condition, the hardness usually ranges from 197–237 HB, but after further heat treatment, it can reach up to 28–32 HRC or higher.

Additionally, 4140 steel exhibits good machinability and moderate weldability, making it highly versatile for engineering applications. It performs well under impact and torsional stress, and offers a balanced combination of strength and ductility. Due to its reliable performance, 4140 steel is widely used in the manufacturing of shafts, gears, axles, crankshafts, connecting rods, drill collars, and other mechanical parts subjected to high stress. Furthermore, it finds significant applications in the automotive, oil and gas, and machinery industries, where strength, toughness, and resistance to fatigue are critical.

Overview

The surface treatment of the steel plate, whether cold or hot-rolled.
4140 steel, a chromium-molybdenum low-alloy steel, belongs to the category of alloy structural steels.
After quenching and tempering, its strength, toughness, and wear resistance are significantly better than plain carbon steels such as 1045.
ZGT Steel supports various hardness customizations and OEM processing services.
Healthy inventories of 4140 steel plate are maintained in all ZGT® Steel distribution centers.
Ability to be machined, drilled, or welded, with excellent performance under impact and fatigue loading.

Available Sizes in 4140 Steel Plate

Due to its wide variety of uses in automotive, oil & gas, and general machinery industries, ZGT Steel keeps a ready stock of the following standard sizes in our distribution centers, but other sizes may be available for special orders.

Benefits of 4140 Steel Plate

In the quenched and tempered condition, 4140 steel is known for its excellent toughness and high fatigue strength. With added chromium and molybdenum, it provides superior wear resistance and hardenability compared to plain carbon steels such as 1045. It also offers good machinability and moderate weldability, making it suitable for a wide range of engineering applications. These properties make 4140 steel especially suitable for components subjected to high stress, such as shafts, gears, and crankshafts, where strength and durability are critical.

Applications & Industries

4140 steel is widely used for mechanical parts requiring high strength, toughness, and wear resistance. Typical applications include shafts, gears, axles, crankshafts, connecting rods, and drill collars. In the automotive industry, it is commonly applied to transmission components, steering parts, and engine components. In the oil and gas sector, 4140 steel is used for downhole tools, drill pipes, and other equipment exposed to heavy stress and fatigue. Additionally, it is applied in general machinery manufacturing for spindles, bolts, and fixtures. Due to its excellent balance of strength and ductility, 4140 steel is extensively used across the automotive, aerospace, machinery, and oilfield industries.