A comparative cost analysis of conventional wrought steel and powder metallurgy (PM) gear manufacturing technologies

Sammanfattning: The transportation industry landscape is going through a massive transformation due to trends such as autonomous and electrified vehicles. The electrification trend has already started to display its ample influence on the automotive industry. New modern power and drivetrains need to be designed and manufactured based on the raising automakers’ requirements e.g. higher performance, better noise vibration harshness (NVH) behaviour. Meanwhile, cost must be minimized in order to obtain or secure market competitiveness.In the highly cost-competitive atmosphere of the manufacturing sector,particularly within the automotive industry, which is the focus of this licentiate,manufacturing firms uninterruptedly seek to develop, adopt and utilise cost models and methods in order to evaluate e.g. their existing production systems or planning new investment for adoption and deployment of new technologies.The industrial case studies, investigated in this licentiate, have gearmanufacturing as the focus. The gear and transmission component manufacturingindustry is an important sector as it provides one of the basic mechanical parts toindustrial segments where motion and power transfer are needed. Two gearmanufacturing techniques namely conventional wrought steel and powdermetallurgy (PM) are compared from a cost perspective. Given the requiredperformance and quality for automotive transmission application, the gearmanufacturing processing routes and their production steps and cost drivers areanalysed and compared through the utilisation of the selected cost model, calledperformance part costing (PPC).The industrial applicability of PPC model is compared with the commonly usedstandard costing, its use and its modified variations among practitioners through the case studies. The pros and cons of each approach are discussed. Given the assumptions made and reported in this licentiate for two different scenarios, the gear manufacturing cost of the analysed PM processing route were 12% to 38% cheaper compared to the conventional wrought steel processing route. However, the acquisition cost for the analysed PM processing route were almost three times higher than that of the conventional wrought steel gear.