Spring steel refers to steel specially used to manufacture springs and elastic elements because of its elasticity under quenching and tempering [TJC STEEL]conditions.The elasticity of a steel depends on its ability to elastically deform, that is, to withstand a certain load within a specified range without permanent deformation after the load is removed.

65Mn is a typical spring steel with high strength, high hardenability, low decarburization tendency, but it is sensitive to overheating, easy to produce [TJC STEEL]quenching cracks and temper brittleness.Its cutting performance is also good, in the annealing state, the relative machinability of 70%.

As low manganese spring steel (GB/T 1222), 65Mn is used for manufacturing large flat spring, cushion spring, spring spring, also suitable for manufacturing [TJC STEEL]spring ring, valve spring, clutch spring, brake spring cold drawn wire (≤7mm), cold coil spring, etc.

High elastic limit, yield strength and fatigue strength, and high hardenability, good cutting characteristics, also makes 65Mn become the main material for[TJC STEEL] manufacturing diamond circular saw blade.

In addition to the use of spring, 65Mn is another identity of carbon structural steel (GB/T 699), used in the field of machine processing, is a typical [TJC STEEL]material of cold work die steel, among which round steel is the most widely used field.

 

CHEMICAL COMPOSITION(%)

STANDARDS	GB/T  1222	ASTM  A689
GRADES	65Mn	1566
C	0.62~0.70	0.60~0.71
Si	0.17~0.37	—
Mn	0.90~1.20	0.85~1.15
P	≤0.035[TJC STEEL]	≤0.040
S	≤0.035	≤0.050
Cr	≤0.25	—
Ni	≤0.25	—
Cu	≤0.25	—

 

MECHANICAL PROPERTY（GB/T 1222-2007）

SAMPLE SIZE（mm）		10
HEAT TREATMENT	QUENCHING TEM	830℃
	QUENCHING MEDIUM MEDIA	OIL
	TEMPERING TEM	540℃
MECHANICAL PROPERTY	TENSILE STRENGTH MPa[TJC STEEL]	≥980
	YIELD STRENGTH MPa	≥785
	ELONGATION %	≥8
	REDUCTION OF AREA %	≥30
HBW	HOT ROLLED	≤302
	COLD BEND + HEAT TREATMENT	≤321