Oil tempered wire is widely used for springs that require extremely high resistance to fatigue, heat, and permanent set in fatigue, including the valve springs of the engine, clutch springs, and suspension springs that are considered important security parts of automobiles. Our group's high-quality oil tempered wire has a large share in both domestic and overseas markets. Our customers choose oil tempered high carbon steel wire for their custom spring and custom wire form manufacturing projects because it is inexpensive, readily available, and easy to work with.

Size Range

.039″ to 1.18″ round/flat wire (1-30mm)

Typical Specifications

• ASTM-A-229 Class I
• ASTM-A-229 Class II
• JIS G3560 / G3561
• DIN 10270
• ISO 8458
• Custom Spec.

Common Trade Names

• 55CrSi
• UNS K07001
• UNS G10650
• ASTM A229
• AISI 1065
• SAE J316T
• 60Si2MnA / 9260H / SUP7 / 56Si7 / 1.5026
• 50CrVA / 6150 / SUP10A /51CrV4 / 1.8159
• 55Cr3 / 5155 / SUP9 / 1.7176
• SAE9254 / 9254V / 60Si2CrA / SUP12 / 54SiCr6 / 1.7102
• 65Mn

Nominal Chemical & Physical Properties

• C: 0.55 - 0.85%
• Mn: 0.60 - 1.20%
• Minimum tensile strength: psi x 103 Class I 165-293, Class II 191-324
• Design stress % minimum tensile: 45
• Modulus of elasticity: psi x 106 30
• Modulus in torsion: psi x 106 11.5
• Maximum operating temperature: 250°F (121°C)
• Rockwell hardness: C42-55

Heat Treating ASTM A 229 Oil Tempered Wire

Oil tempered is delivered in pre-tempered condition. Therefore, no further hardening can be obtained via heat treating. However, depending on the application, springs and wire forms will undergo a stress-relieving process.

Oil tempered wire for springs

Oil tempered wire for Valve spring

Oil tempered wire for Suspension spring