Gears are key structural parts of a manual transmission. Typically, gears are subjected to impulse stress during meshing, with stress peaks located near the gear surface. Therefore, gears mainly require high strength and high wear resistance at or near the surface. Inaccurate gear geometry or components can reduce gear life and load capacity, and increase noise. Therefore, the quality requirements for transmission gears are generally very high, usually higher than DIN7. In addition to the requirements for strength and noise, the requirements for improving economy and performance are also added. Gear loads are high stresses at or near the surface, so full density of the entire part is not required. Selective surface densification is suitable for this loading situation, the process can form a densified layer on the surface of the part, the surface porosity is close to zero, and the core porosity is generally around 10%. In recent years, PMG has developed the DensiForm process, which selectively increases the density of the surface of the sintered gear while still maintaining the porosity of the core, allowing the formation of a fully dense surface layer to a depth of 0.5-1mm. Produced by powder metallurgy process, the gear performance is fully used in current transmissions.
The parts of the manual transmission synchronization module are the development objects of the powder metallurgy parts industry. In the next few years, these parts will contribute to the rapid growth of the powder metallurgy parts industry. In recent years, the overall and surface properties of powder metallurgy steel and functional materials have been improved. , these advances are achieved through the use of advanced production equipment and processes, such as furnaces that can sinter Cr-alloyed steel or DensiForm’s selective densification process. The approval of new powder metallurgy components, including sliding sleeves and load gears, opens the market for new applications of powder metallurgy processes in transmissions.
Post time: Apr-08-2022