A statistical approach to comparing wheel hub forging processes

Structural components used in the automotive industry offer an attractive opportunity for exploring alternate material sources and different manufacturing routes because economic globalization continually intensifies competition and increases costs. While economic parameters are important in the choice of manufacturing process, the final decision is usually dictated by desirable component characteristics and reliability. Integrated process flows involving steel making, forging, and heat treatments can reduce the impact on forged and heat-treated hubs. However, speed differences in hot forging operations, sources, and heat treatment equipment differences still influence the ultimate manufacturing decision. The aim of this study is to demonstrate interdisciplinary effort in comparing two different wheel hub forging processes by quantifying final product characteristics that are linked to their microstructures and to understand the possible impacts on quality assurance of the final parts. Brinell hardness measurements were performed as part of the analysis, and both non-parametric and parametric statistical procedures were applied to data taken from samples that were manufactured under real industry conditions. In addition, scanning electron microscopy was utilized to support analytical results.