70Si3Mn (spring steel) metallographic diagram

Introduction

60Si2Mn and 60Si3Mn are commonly known as spring steels. They are also known as silicon manganese steel, because of their high content of silicon and manganese. These steels are alloyed with other elements such as chromium and molybdenum, in order to enhance their properties. A typical microstructure of 60Si2Mn or 60Si3Mn is a ferritic structure with a large amount of martensite. The balanced composition of these steels results in excellent mechanical and physical properties. These steels are used in the manufacture of a wide range of applications such as automotive components, appliances, gaskets, textiles, machine parts and more.

Process

In order to obtain high mechanical properties, the 60Si2Mn and 60Si3Mn steel must be heat-treated. This heat treatment process involves the strengthening of the steel by bringing it to the desired temperature and then cooling it off rapidly. This will produce a more uniform microstructure and allow for a finer grain size. The cooling rate depends on the manganese content. When the steel is cooled, the carbon atoms tend to form finer and smaller grain sizes, which then leads to a stronger,more durable steel.

Characteristics

60Si2Mn and 60Si3Mn are capable of withstanding higher temperatures than ordinary carbon steels, due to their increased silicon and manganese content. They also show good oxidation and corrosion resistance. The addition of chromium and molybdenum further improves the strength of these steels and also provides superior toughness. This allows for a higher resistance to sudden shock or impact and makes them suitable for applications requiring a strong and durable material.

Applications

60Si2Mn and 60Si3Mn are commonly used in a variety of applications such as automotive components, appliances, gaskets, textiles, and machine parts. Due to their increased strength and toughness, these steels are an ideal choice for applications where a stronger and more durable material is needed. The good mechanical properties also ensure that these steels are suitable for bending, forging, and welding. Other common applications for these steels include springs, fasteners, nuts, and bolts.

Conclusion

60Si2Mn and 60Si3Mn are commonly known as spring steels because of their strong and durable properties. They are both alloyed with other elements such as chromium and molybdenum and are used in a variety of applications that require a strong and durable material. The heat treatment of these steels will provide a more uniform that microstructure and allow for a finer grain size. The addition of chromium and molybdenum improves the strength of these steels and also provides superior toughness. Overall, these steels are capable of withstanding higher temperatures than most other carbon steels and provide great resistance to oxidation and corrosion.

60Si2MnA is a kind of silicon-manganese spring steel produced in China. It is frequently used in automobile, engineering machinery and other mechanical products. On the basis of normalizing, the mechanical properties of it can reach HB240-320.

The chemical composition of 60Si2MnA are as follows: Carbon 0.56-0.64%, Silicon 0.17-0.37%, Manganese 0.90-1.20%, Si-Mn-Fe (balance), P≤0.035%, S≤0.035%, respectively.

Its thickness is between 0.5-8mm, and It is hot-rolled to be plates or strip steel. 60Si2MnA has good effective and performance, it can remain the best flexibility and toughness in low temperature. Its hyper elasticity make it works in long strode and high impact load in dynamic running state.

In metallographic examination, it appears martensite-bainite two micro-structures. Equiaxed martensite include α+FeMn which is cementite, carbon grains or body center phase and also some sub-micron spheres or micro-grains structure around them. Bainite includes needle-like structure, ferrite has lamellar structure. And there are also some inter-granular precipitates which are cementite or finely distributed carbide net in boundary. The carbon content is low and in the ferrite-austenite boundary, there is some trace amount of acicular ferrite.

60Si2MnA steel has great performance like high strength, good toughness, flexibility and hardenability, good bearing performance and fatigue limit. All these can make it an well-developed and most commonly used kind of spring steel.

It is applicable to the production of springs in vehicles, railway, military and other fields. And it is also extensively used in automobiles, engineering machinery and other mechanical products.