Bainite Transformation Behavior Of 100Cr6 Bearing Steel

Publish Time: 06/28 2021 Author: Site Editor Visit: 14007

The high-carbon chromium 100Cr6 bearing steel, which accounts for the largest amount in the market, has a conventional structure of high-carbon twin martensite + carbide + retained austenite when in use. With the development of the bearing industry, the performance requirements for bearing steel have become more and more demanding. Based on the improvement of material properties brought about by the bainite structure, the bainite isothermal treatment method of bearing steel is worthy of popularization and application.

Without affecting the final performance of the bearing steel, scholars are very interested in how to reduce the incubation period of bainite transformation. Use the beneficial properties of bainite isothermal structure to improve the process to reduce the phase transition time. Based on the theory of thermodynamics and dynamics microstructure control, this project studied the phase evolution law of 100Cr6 bearing steel during isothermal treatment, and proposed a short-term bainite treatment method.

The experimental material is selected as 1.02C-1.49Cr-0.23Si-0.37Mn (mass fraction, %) high carbon chromium bearing steel smelted in ZGJL0.05-100-2.5D vacuum induction furnace, and the room temperature structure is ferrite after spheroidizing annealing Spherical alloy carbides are dispersed on the matrix. The heat treatment experiment was performed on the DIL805A dilatometer. After heating to 860°C at a heating rate of 5°C/s for 30 minutes, it became a mixed structure of austenite + undissolved spherical alloy carbide (3%), and then quenched to different Perform bainite isothermal treatment at temperature to study the law of bainite isothermal transformation; discuss and analyze the stability of undercooled austenite during the bainite transformation process; propose a new two-part Fabry bainite treatment process; use ZEISSULTRA55 Thermal field emission scanning electron microscope for organization analysis; Bainite and internal fine structure research on TecnaiF30 transmission electron microscope; physical property analysis on D/MAX-RB12KW rotating anode X-ray diffractometer; HVS-1000 digital microscope Test the Vickers hardness on the hardness tester; test the abrasive wear performance on the nitrate disc abrasion tester. the result shows:

The temperature range of the nose tip of the bainite isothermal transformation is 300～350℃. Considering the phase change incubation period and hardness, it is concluded that the isothermal treatment at 250℃ is the optimal process. The low phase transition temperature promotes the fine and dispersed distribution of precipitates, and the bainite laths grow in a certain orientation;
The content of retained austenite is highest when it is kept at 250°C for 20 minutes and then cooled to room temperature. When the holding time is lower than this, part of the austenite undergoes martensite transformation during the cooling process; after the holding time is longer than 20 minutes, when it is cooled to room temperature, the austenite does not undergo martensite transformation;
Two-step processing can significantly reduce processing time. In the second step, the temperature is kept at 270°C for 5 minutes. The total time of the two-stage transformation is about 27% of that of the conventional process, and the retained austenite content is only about 6%, while the hardness and wear performance are not significantly reduced.

Please keep the source and address of this article for reprinting:Bainite Transformation Behavior Of 100Cr6 Bearing Steel

Minghe Die Casting Company are dedicated to manufacture and provide quality and high performance Casting Parts(metal die casting parts range mainly include Thin-Wall Die Casting,Hot Chamber Die Casting,Cold Chamber Die Casting),Round Service(Die Casting Service,Cnc Machining,Mold Making,Surface Treatment).Any custom Aluminum die casting, magnesium or Zamak/zinc die casting and other castings requirements are welcome to contact us.

ISO90012015 AND ITAF 16949 CASTING COMPANY SHOP

Under the control of ISO9001 and TS 16949,All processes are carried out through hundreds of advanced die casting machines, 5-axis machines, and other facilities, ranging from blasters to Ultra Sonic washing machines.Minghe not only has advanced equipment but also have professional team of experienced engineers,operators and inspectors to make the customer’s design come true.

POWERFUL ALUMINUM DIE CASTING WITH ISO90012015

Contract manufacturer of die castings. Capabilities include cold chamber aluminum die casting parts from 0.15 lbs. to 6 lbs., quick change set up, and machining. Value-added services include polishing, vibrating, deburring, shot blasting, painting, plating, coating, assembly, and tooling. Materials worked with include alloys such as 360, 380, 383, and 413.

Zinc die casting design assistance/concurrent engineering services. Custom manufacturer of precision zinc die castings. Miniature castings, high pressure die castings, multi-slide mold castings, conventional mold castings, unit die and independent die castings and cavity sealed castings can be manufactured. Castings can be manufactured in lengths and widths up to 24 in. in +/-0.0005 in. tolerance.

ISO 9001 2015 certified manufacturer of die cast magnesium and mold manufacturing

ISO 9001: 2015 certified manufacturer of die cast magnesium, Capabilities include high-pressure magnesium die casting up to 200 ton hot chamber & 3000 ton cold chamber, tooling design, polishing, molding, machining, powder & liquid painting, full QA with CMM capabilities, assembly, packaging & delivery.

Minghe Casting Additional Casting Service-investment casting etc

ITAF16949 certified. Additional Casting Service Include investment casting,sand casting,Gravity Casting, Lost Foam Casting,Centrifugal Casting,Vacuum Casting,Permanent Mold Casting,.Capabilities include EDI, engineering assistance, solid modeling and secondary processing.

Casting Industries Parts Case Studies for: Cars, Bikes, Aircraft, Musical instruments, Watercraft, Optical devices, Sensors, Models, Electronic devices, Enclosures, Clocks, Machinery, Engines, Furniture, Jewelry, Jigs, Telecom, Lighting, Medical devices, Photographic devices, Robots, Sculptures, Sound equipment, Sporting equipment, Tooling, Toys and more.