GCr15 hot rolled steel round bars

GCr15 is a common steel which is used to produce balls and rings of bearing. The product has characteristics of the uniform-chemical composition, low percentage of harmful elements, high purity, well-distributed carbide, good surface quality. It also has characteristics of a wide scope of plastic，stable heat-treatment quality, uniform, and high hardness, high wear resistance，high strength of touching fatigue. It has excellent machining property after spheroidize annealing. GB GCr15 bearing steel is GB standard Alloy Bearing steel, It belong to the high-quality high carbon, alloy chromium, manganese steel. GB GCr15 properties is a chromium, manganese alloy steel specification. GCr15 is equivalent to AISI 52100, DIN 100Cr6. Most applications can replace each other.

Chemical composition

C(％)	0.95～1.05	Si(％)	0.15～0.35	Mn(％)	0.25～0.45	P(％)	≤0.025
S(％)	≤0.025	Cr(％)	1.40～1.65

Mechanical Properties

The mechanical properties of annealed GB GCr15 bearing steel (typical for steel) are outlined in the table below:

Tensile	Yield	Bulk modulus	Shear modulus	Poisson’s ratio	Thermal conductivity
MPa	Mpa	Gpa	Gpa		W/mK
520	415 Min	140	80	0.27-0.30	46.6

Heat treatment Related

• Annealing of GCr15 Alloy bearing steel

Slowly heated to 790-810 ℃ and allow enough times, let the steel to be thoroughly heated, Then cool slowly in the furnace. Different annealing ways will get different hardness.The GCr15 bearing steel will get Hardness MAX 248 HB （Brinell hardness）.

• Quenching and temperature of GCr15 Alloy bearing steel

Heated slowly to 860°C, Then quenching by oil get 62 to 66 HRc hardness. High temperature tempering: 650-700℃，cool in air, get hardness 22 to 30HRC. Low temperature tempering: 150-170 ℃， Cool  in ari, get 61-66HRC hardness.

• Hot work and cold work of GCr15 Alloy bearing steel

GB GCr15 steel can hot worked at 205 to 538°C, GCr15 Bearing steel can be cold worked using conventional techniques in the annealed or normalized conditions.

Applications

GB GCr15 steel is widely used for a variety of applications in the used to the bearings in rotating machinery. Typical applications such as valve bodies, pumps and fittings, the high load of wheel, bolts, double-headed bolts, gears, internal combustion engine. Electric locomotives, machine tools, tractors, steel rolling equipment, boring machine, railway vehicle, and mining machinery transmission shaft on the steel ball, roller and shaft sleeve, etc.