Knowledge, bearing steel and bearing

Bearing steel is used in the manufacture of ball bearing, roller bearing ring and steel. Bearing is in the work under great pressure and friction, so the requirement bearing steel has high and even hardness and wear resistance, and high elastic limit. On the uniformity of the chemical composition of bearing steel, the content and distribution of non-metallic inclusions are very demanding, and the distribution of the carbide bearing steel is also called the high carbon steel luo, a carbon Wc is approximately 1%, Wcr luo content is 0. 5% - 1. 65%. The physical properties of the bearing steel mainly to check the decarburization layer, non-metallic inclusion, microstructure, macrostructure. Usually in hot rolled annealed, cold-drawn annealing delivery of the goods. Delivery status should be indicated in the contract. The macrostructure of steel must be free of shrinkage cavity and subcutaneous bubbles, white spots and microscopic pore. Which center loose loose, shall not be more than 1. Level 5, segregation shall not exceed the level 2. Steel annealing organization should be evenly distributed fine granular pearlite. Decarburization layer depth, non-metallic inclusions and carbide uneven degree should be in conformity with the relevant national standards of the relevant provisions. Bearing steel is divided into high carbon luo, luo bearing steel bearing steel, carburized bearing steel, high temperature stainless bearing steel, the bearing steel and the magnetic bearing steel six categories. 1 high carbon chromium bearing steel, in brand head plus symbol 'G', but does not indicate the carbon content. Chromium content in a few parts per thousand, other alloying elements in the alloy structural steel alloy content. For example: the average chromium content is 1-50% of bearing steel, the brand is expressed as 'GCr15. 2 carburizing bearing steel, alloy structural steel grades said method, the other in brand head plus symbol 'G'. For example: 'the G20 CrNiMo'. Senior high quality carburizing bearing steel, add an 'A' at the end of the brand. For example: 'G20CrNiMoA'. 3 high carbon chromium stainless bearing steel and high temperature bearing steel, stainless steel and heat resistant steel brand representation, symbol 'G' brand head all the time. For example: high carbon chromium stainless bearing steel and high temperature bearing steel cr18 9 '10 cr14mo'.