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What is 52100 Steel
52100 steel seems to have a different naming structure than the other three- or four-digit steels, but this is only due to the specific differences between the SAE and AISI naming indexes. The first digit (5) denotes that this steel is primarily alloyed with chromium, and the second digit (2) represents an alloying percentage greater than 1%. In other words, the second digit does not specify the exact percentage of chromium, but only that it is alloyed at a higher percentage than other similar steels. The last three digits show the average percentage of carbon used in the steel; so, for 52100 steel, there is on average 1.00 % carbon used in its blend. Below is a list showing the exact chemical composition of 52100 steel, with tolerances:
Component elements of 52100 steel
0.98- 1.1% Carbon
1.3-1.6% Chromium
0.25-0.45% Manganese
<= 0.025% Phosphorus
0.15-0.3% Silicon
<= 0.025% Sulfur
To learn more about the differences between steel grades, read our article on the types of steels.
52100 steel is a high carbon chromium alloy steel that has a density of 7.81 g/cm3 (0.282 lb/in3). It can be hardened via cold and hot working processes and responds to annealing and tempering and can be strengthened using the heat treatment process. It is readily forged and formed, as well as machined, from its annealed condition. While generally not used for welding, 52100 steel is particularly useful in bearings, mill rolls, and vehicle parts thanks to its combination of strength, hardness, and workability. The most common form of 52100 stock is bar stock, but it can also be found in tube, wire, flat-rolled, and forging stocks as well.
Mechanical Properties
Table 1: Summary of mechanical properties for 52100 steel.
Mechanical Properties Metric English
Modulus of Elasticity 210 GPa 30500 ksi
Bulk Modulus 160 GPa 23200 ksi
Shear Modulus 80 GPa 11600 ksi
Fracture Toughness 15.4-18.7 MPa-m½ 14.0 – 17.0 ksi-in½
Machinability 40% 40%
Above, in Table 1, some mechanical properties of 52100 steel are shown to illustrate its useful working characteristics. This section will briefly explain each parameter and how it relates to the applications of 52100 steel.
Type 52100 steel has a modulus of elasticity of 210 GPa. This metric describes the elastic stiffness of a material, where a higher elastic modulus denotes a stiffer metal. It is important to understand the modulus of elasticity of a material if it must be machined, as a less stiff material tends to gum and gall up on machine mills, while a stiffer material will wear down machine bits faster but generally machine better. 52100 steel responds well to machining processes, and this is clearly seen through its large elastic modulus.
The bulk modulus is a material property often reserved for liquids, but it is commonly used with reference to steel as it describes a metal’s resistance to compression, or a reduction in volume when uniformly compressed. This value is especially important to 52100 steel, as it is typically used in bearings which can be under this type of constant compressive force or load. As is seen in Table 1, the bulk modulus of 52100 steel is 160 GPa, which is about twice as strong as most aluminum alloys.
The shear modulus of a material is another representation of a material’s response to stress, which in this case is shearing stress. Shear stress is where two forces oppose each other along a plane of a material, like how scissors cut paper, or a saw cuts a cylindrical bar. It is an important value to understand if a metal will be cut from stock and twisted/formed radially, as the material must not shear off or fracture under these conditions. The shear modulus of 52100 steel is 80 GPa, which is typical for steel and is suitable for cutting from flat rolls and wires.
The fracture toughness shows a material’s ability to resist fracture. It denotes the stress at which cracks will propagate through the material unhindered by other effects and is vital in understanding how a material fails in brittle fracture. A material with a high fracture toughness generally fails in ductile fracture, while those materials with a low fracture toughness simply shatter. From its fracture toughness (15.4-18.7 MPa-m½), 52100 steel is clearly is prone to a more ductile fracture scenario, which is ideal for such steel.
Finally, the machinability of a material is a qualitative, comparative measure of how well a metal reacts to machining procedures. It is often provided as a percentage, where reference steel is set at 100% and other steels are given a percentage in reference to this steel. The machinability rating seen in Table 1 is in reference to AISI 1212 steel, which is given 100% machinability on this scale. A percentage lower than 100% (such as the case with 52100 steel) means it is more difficult to machine than the reference steel. This does not mean that 52100 is not suited for machining; on the contrary, it can be readily machined, but its hardness simply wears down die and mill bits faster.
Applications of 52100 Steel
As previously discussed, 52100 steel most often used in steel bearings, as well as bearing manufacturing equipment. Its toughness and hardness lend it to be used in blades and cutlery, though it is trickier to heat-treat than some other, more common blade steels. Below is a list of other common applications of 52100 steel:
Anti-friction bearings
Mill rolls
Punches, taps, dies
Automotive and aircraft parts
Fasteners
and more.
If 52100 steel sounds like it could be useful to your project, contact your supplier and see if they agree. They will always have the best information relevant to your specifications and can advise you about suitable options and alternatives.
Summary
This article presented a brief summary of the properties, strength, and applications of 52100 steel. For information on other products, consult our additional guides or visit the XTJ to locate potential sources of supply or view details on specific products.
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