A study of the efficiency of spur gears made of powder metallurgy materials – ground versus super-finished surfaces. (March 2016)

• Record Type: Journal Article
• Authors: Li, Xinmin; Sosa, Mario; Andersson, Martin; Olofsson, Ulf
• Is Part Of: Tribology international. Volume 95(2016)
• Page Start: 211
• Page End: 220
• Publication Date: 2016-03
• Subjects: Powder metallurgy gear -- Efficiency -- Ground -- Super-finished; Tribology -- Periodicals; 621.89
• DOI: 10.1016/j.triboint.2015.11.021
• Languages: English
• ISSNs: 0301-679X

Abstract

Abstract: Power loss is one of the main concerns in gear transmission systems. In this study a recirculating power back-to-back FZG test rig was used to investigate the efficiency of spur gears made of powder metallurgy (PM) material using two different surface manufacturing methods (ground and super-finished). The results were compared with previously presented results of standard gear material from the same test rig. The influence of the material (Wrought steel or PM) and surface roughness on the gear mesh efficiency and the total efficiency of the gearbox were analyzed in detail. The Young's modulus for PM materials is lower than for conventional gear steel. This may influence gear tooth bending and the efficiency of the gear transmission. Gear contact simulation results showed that the influence of gear tooth bending on PM gear transmission efficiency can be ignored in the FZG gear geometry. Higher surface energy combined with a smoother surface led to a lower transmission efficiency for the super-finished powder metallurgy gear combination compared to the standard gear material. Highlights: Influence of elastic properties of PM material on gear efficiency can be neglected. Gear efficiency is closely related to material combinations and surface roughness. Efficiency of the super-finished PM material gear is lower than that of the ground. Low efficiency of super-finished PM gear is dues to adhesive material transfer.