INVESTIGATION OF LOAD ADAPTED GEARS AND SHAFTS MANUFACTURED BY COMPOUND-FORGING

Abstract

The demand for economic processes concerning manufacturing technology, cycle time and material properties has led to the development of near net-shape techniques. Precision forging is a well-known manufacturing technology to achieve high output rates. An approach of optimization concerning the part material to produce load-adapted material properties is the so-called compound-forging. Therefore, two different alloys are forge-welded together. Non-tempering and tempering steels are used to compound-forge gears with a hard and wear-resistant surface layer as well as a ductile bulk material. Compound-forging was developed to forge spur gears and shall now be introduced to manufacture helical gears and shafts. For the production of gears and shafts billets made from non-tempering steels are forge-welded together with billets consisting of tempering steels by precision forging as well as indirect impact extrusion. In this paper, the comparison of the material properties of compound-forged gear wheels and shafts with a hard and wear resistant surface layer and a ductile bulk material is given. Mechanical properties as well as the micro-structure of the parts were investigated. The results of the investigations show a load-adapted material distribution of forge-welded materials for the production of gears and shafts.