Shandong Xinkaite Bearing Co.,Ltd.
Unified Social Credit Code: 9137 1525MA3C 5428XP
Production Department
Address: Xu Village Industrial Garden, Gan Town, Guan County, Shandong
Tel: +86 635 5638235
Fax: +86 635 5638808
Mobile: +86 15563545668
Service Hotline: 4000 305204 Sales Department
Address: 314 Puli Mansion, Beixiaoxinzhuang West Street, Jinan City, Shandong
Tel: +86 15688862750
Fax: +86 531 87901699
WhatsApp: +86 15688862750
Skype: live:XinKaite
Email: xkte@xinkaite.com
Five common ways of surface strengthening of bearing steel
Clicks:2655 Date:8-10
Five common ways of surface strengthening of bearing steel
1 surface deformation strengthening
A mechanical process that causes a plastic deformation on the surface of a metal layer to form a hardened layer of high hardness and strength. This surface strengthening method is called surface deformation hardening, also known as working hardening. Including shot blasting, sand blasting, cold extrusion, rolling, cold rolling and impact, explosion impact strengthening, etc.. The characteristics of these methods are: strengthen the dislocation density, subgrain structure refinement, so that the hardness and strength increased, the surface roughness decreases, can significantly improve the surface fatigue strength and reduce fatigue notch sensitivity. The strengthening method has the advantages of simple process and obvious effect, and there is no obvious limit between the hardening layer and the substrate, and the structure is coherent and is not easy to fall off during use. Most of these methods have been applied in the bearing industry: the surface impact strengthening of rolling bodies is the application of this method, and precision rolling has become a new method for machining and strengthening rings.
2, surface heat treatment strengthening
The use of solid-state phase transformation, through rapid heating method of surface hardening of parts, known as surface heat treatment, commonly known as surface hardening. Including flame heating quenching, high (medium) frequency induction heating quenching, laser heating or electron beam heating quenching, etc.. The characteristics of these methods are: local heating quenching, small deformation of the workpiece, heating speed, high production efficiency, short heating time, surface oxidation decarburization is very slight.
The method is especially effective in improving the wear resistance and fatigue strength of large and super large bearing parts subjected to certain impact loads.
3 銆?chemical heat treatment strengthening
The method of modifying the chemical composition of a metal surface layer by means of the solid diffusion of a certain element to achieve surface strengthening is called chemical heat treatment intensification, also known as diffusion heat treatment. Including boronizing, infiltration of metals, carburizing and carbonitriding, nitriding and nitrocarburizing, infiltration of sulfur and nitrogen, carbonitriding, chromizing, aluminizing and chromium aluminum and silicon cementation, graphitization, and so on, with various characteristics. Permeating or dissolving into a base metal forming a solid solution or combining with other metal elements to form a compound. In a word, the permeating element can change the chemical composition of the surface layer, and can also get different phase structure. The treatment process of carburizing bearing steel parts and the surface nitriding strengthening of needle bearing sleeve are all the strengthening methods.
4, surface metallurgy strengthening
The use of surface metallurgy to intensify the re melting and solidification of metal on the surface of the workpiece in order to obtain the desired component or surface strengthening of the tissue is called surface metallurgy. It includes surface autolysis alloy or composite powder coating, surface melting crystallization or amorphous treatment, surface alloying and other methods. Is characterized by rapid heating of high energy density, the metal surface alloying layer or coating material on the surface of metal melting, followed by their own cooling solidification strengthening layer to obtain special structure or of the specific performance. This particular structure may be a refinement of crystalline structures, or possibly supersaturated phases, metastable phases, or even amorphous structures, depending on the process parameters and methods of surface metallurgy. In the rolling bearing industry, laser heating strengthening research has been done on the working surface of micro bearings, and the effect is good.
5 surface film strengthening
Application of physical or chemical methods in metal surface coating on the basis of different material properties of the strengthening film, known as surface film strengthening. It includes electroplating, electroless plating (chrome, nickel, copper, silver, etc.) and composite plating, brush plating or conversion processing, including high technology developed rapidly in recent years, such as CVD, PVD, P-CVD and other vapor deposition thin film strengthening method and ion implantation surface strengthening technology (also called atomic metallurgical technology and so on). Their common feature is that they can form a specific performance film on the surface of the work, so as to strengthen the wear resistance, fatigue resistance, corrosion resistance and self lubrication of the surface. For example, ion implantation bearing working surface strengthening technology, can make the working surface of the bearing wear resistance, corrosion resistance, resistance and contact fatigue performance has been significantly improved, so that the service life of the bearing has been growing exponentially.
