1. 65, 70, 85: High strength, hardness, yield ratio can be obtained, but the hardenability is small, the heat resistance is not good, and the ability to withstand dynamic load and fatigue load is low. It is widely used, but it is mostly used for working temperature. Small springs that are not tall or larger springs that are not important. Such as springs for automobiles, tractors, railway vehicles and general machinery
65Mn has simple composition, better hardenability, comprehensive mechanical properties, decarburization and other process properties than carbon steel, but it is more sensitive to overheating, has temper brittleness, and is easy to crack after quenching. The price is low and the dosage is large. It manufactures various small cross-section flat springs, round springs, springs, etc., as well as valve springs, spring rings, shock absorbers and clutch springs, brake springs, etc.
2. 55Si2Mn, 60Si2Mn, 60Si2MnA have high silicon content (Wsi) (up to 2.00%),
High strength and good elasticity. Good stability against tempering. Easy to decarburize and graphitize. Hardenability is not high.
The main spring steel is very versatile. Manufacture all kinds of springs, such as leaf springs and coil springs for automobiles, locomotives, and tractors, cylinder safety valve springs, and some important springs that work under high stress, and springs with severe wear.
55Si2MnB has significantly improved hardenability due to its boron content. Front and rear suspension springs and auxiliary springs for light and medium-sized cars.
55Si2MnB The steel grade developed by our country has better hardenability, comprehensive mechanical properties and fatigue properties than 60Si2Mn steel. It is mainly used to manufacture leaf springs for medium and small cars. The use effect is good. It can also be used to make leaf springs and coil springs with medium cross-sectional dimensions. .
3. 60Si2CrA 60Si2CrVA
High-strength spring steel. High hardenability, good heat treatment process performance. Due to the high strength, the spring should be processed in time to eliminate the internal stress after rolling it to make an important large spring with a large load. 60Si2CrA can be used to make steam turbine seal springs, adjusting springs, condenser support springs, high-pressure water pump disc springs, etc. 60Si2CrVA steel also makes very important springs, such as spring hooks for conventional weapons and springs for crushers.
The outstanding advantage of 60CrMnA is that it has good hardenability, as well as good hot workability, comprehensive mechanical properties, and decarburization resistance. Various important springs with large cross-sections, such as large leaf springs and coil springs for automobiles and locomotives.
The hardenability is the highest among all existing spring steels. Mechanical properties, anti-tempering stability, etc. are also super large springs used in large civil constructions, heavy vehicles, machinery, etc. The thickness of the steel plate can be more than 35mm, and the diameter of the round steel can be more than 60mm
A small amount of vanadium improves elasticity, strength, yield ratio and elastic resistance, refines crystal grains and reduces the tendency of decarburization. The carbon content is smaller, and the plasticity and toughness are better than other spring steels. High hardenability and good fatigue performance. Various important coil springs are especially suitable for springs with high working stress amplitude and strict fatigue performance requirements, such as valve springs, injector springs, cylinder expansion rings, safety valve springs, etc.
The hardenability is higher than that of 60CrMnA, and other leaf springs, coil springs, torsion springs with similar properties and larger sizes.
High-strength heat-resistant spring steel. The hardenability is very good. High-temperature relaxation resistance and thermal processing performance are also very good. Heat-resistant springs with working temperature below 500~C, such as steam turbine main steam valve springs, steam seal springs, boiler safety valve springs, 400t boiler disc valve springs, etc.