Grade 65Mn Steel High Carbon Spring Steel

65Mn is a kind of spring steel. Brand meaning: 65 -- carbon content 0.65% (actually usually 0.62% ~ 0.70%); Mn - the main alloying element is manganese (the unmarked figure behind indicates that the content is less than 1.5%).

Actual chemical composition:

C: 0.62% ~ 0.70%;

Mn: 0.9% ~ 1.2%;

Si: 0.17% ~ 0.37%.

Brand :65Mn

China ISC:U21653

Corresponding standard :GB/T 1222-2007

Spring steel

Spring Steels

Classification: Carbon steel

Properties: Strength, elasticity and fatigue resistance

Tag: High quality carbon structural steel

Description :65Mn has high strength, good hardenability and comprehensive mechanical properties, small decarburization tendency, but has overheating sensitivity and tempering brittleness, and is prone to quenching cracks.

65Mn is used for slightly larger ordinary springs, such as 5~10mm leaf springs and wire diameter 1~15nm coil springs, can also be used as spring rings, valve springs, spring, shock absorbers and clutch reeds, as well as cold coil springs made of drawing steel wire

This standard applies to spring round steel and square steel (referred to as bar) with diameter or side length not greater than 100mm, spring flat steel with thickness not greater than 40mm, spring steel wire with diameter not greater than 25nm (excluding oil quenched and tempered spring wire wire wire (YB/T)

5365)). Rods with diameters or side lengths greater than 100mm, flat steel with thicknesses greater than 40mm and rods with diameters greater than 25mm can also be supplied after negotiation between the supply and demand parties.

The grades and chemical compositions specified in this standard also apply to ingot, billet and its products

Equivalent Of 65Mn alloy Spring Steel

Heat treatment Related

Annealing of 65Mn Spring Steel

At first Slowly heated to 730 ℃ and allow enough times, let the steel to be thoroughly heated, Then cool slowly in the furnace. Then 65Mn tool steel will get MAX 250 HB （Brinell hardness）.

Hardening of 65Mn Spring Steel

At the beginning, 65Mn steels should be heated uniformly to 830-860°C (1526-1580°F) until completely heated through. After about 30 min per 25 mm of ruling section is to be provided and then the steels should be immediately quenched in oil. Tempering of 65Mn Spring Steel

Tempering of 65Mn steels is performed at 540°C, Soak well at the selected temperature and soak for at least one hour per 25mm of total thickness. Hardness values at different temperatures after tempering

Mechanical Properties

The mechanical properties of 65Mn Spring Steels are outlined in the following table.