Main Sector of relevance\IRC classification 8. Industrial Manufacturing, Material and Transport Technologies
8.45 The technique of bearing capacity enhancement upon machinability stabilization of gear wheels made from intermediate-carbon alumino-containing chromium-molybdenum steel
Developers’ contact information
State Scientific Institution “Joint Institute of Mechanical
Engineering of the National Academy of Sciences of Belarus”
12, Akademicheskaya Str., Minsk 220072
Tel/fax: +375 (17) 210-07-49; Web-site:
http://oim.by
Summary
The technique of heat treatment of gear wheels made from intermediate-carbon alumino-containing chromium-molybdenum steel has been worked out for their machinability stabilization upon generation of cog geometry and for enhancement of parts bearing capacity in service.
Description
The technique of heat treatment of gear wheels made from intermediate-carbon alumino-containing chromium-molybdenum steel consists in heat hardening and drawback at specified temperature, non-movable soak at these temperatures and their further air cooling. The achieved hardness of material of gear wheels heat-treated by the specified technique - 241-269 НВ, structure – sorbite with decarburizated stringers along the junction lines of original crystals.
Technology type
Technical advantages and economic benefits
This technique makes it possible to raise hardness of gear wheel core and reduce the heat treatment duration. Calculation resource enhancement of gear wheels life increases up to 3-4 times upon optimization of gear wheel surface, resulting from surface impregnation at the level of 800-900 НV5. This surface hardness level is provided by surface impregnation.
Technology differentiation and uniqueness
The microhardness of the resulting sorbite is 250-270 НV0,05, therefore machinability of steel heat-treated by the specified mode and the tool deterioration upon cog shaping have much in common with machinability index of steel with ferrite-perlitic structure. The achieved sorbit structure provides gear wheel strength.
Context in which technology was identified
The specified technique is used in the heat-treatment shops of State Unitary Manufacturing Enterprise “BelAZ”.
Technological keywords
Heat treatment, heat hardening, drawback, microstructure, microhardness, crystal junction line, gear wheel endurance life.
Development Stage
Intellectual property rights
Range of applications
Heat-treating shops of mechanical-engineering industries.
Classifier Used at the EU Innovation Relay Centres
Preferable Regions
Practical experience
The steel is successfully used at the shops of State Unitary Manufacturing Enterprise “BelAZ”.
Environmental impact
According to processes of production in the shops of State Unitary Manufacturing Enterprise “BelAZ”.
Type of collaboration sought
Terms and restrictions
—
Available technical assistance