100+

Customers
Served

20+

Countries
Shipped

520+

Manufacturing
Partners

1000+

Machines

Properties of Alloy Steel 4340


Ultimate tensile strength (MPa) 690-1080
Yield strength (MPa) 470-630
Young's modulus (modulus of elasticity) (GPa) 205-213
Elongation at break(%) 15-22
Fatigue Strength (MPa) 450-600
Hardness (Brinell) 217 HB
Density (g/cm³) 7.85
Corrosion resistance Moderate


Weldability Excellent
Maximum service temperature(°C) 613--652
Thermal expansion coefficent (10-6/ºC) 11.5-13
Thermal conductivity (W/(m⋅°C)) 35-50
Electrical resistivity (μΩ.cm) 18-27
Post-Processing Annealing, Tempering
Magnetism Semi-magnetic
Common applications Engine parts, Drive shafts

Available Finishes

alloy-steel-4340-surface-finish-services-clarwe

Clarwe provides a wide range ofsurface finishes through its alloy steelCNC machining service, designed to elevate the quality of each machined component. Each finish is specifically chosen to improve both the mechanical characteristics and the visual appeal of thealloy steel parts.

Industries specialized

ISO 9100D Certified Aerospace Parts

Aerospace

AS9100-certified flight-critical parts: CNC machining, sheet metal & tubing for turbines, mounts & actuators

IATF 16949 certified Automotive Parts

Automotive

IATF 16949-compliant automotive solutions: CNC machining, injection molding, urethane casting & more

Quality Certified industrial parts

Consumer Products

Scale from 1 to 1M+ consumer product units with full QA ownership and compliance

ISO 13485 certified quality Medical Parts

Medical

ISO 13485-certified surgical tools & implants: Precision CNC, cleanroom molding & biocompatible casting




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