Quantifying the effects of parts consolidation and development costs on material selection decisions: A process-based costing approach

Product designers must continually assess trade-offs among various performance attributes and cost. Materials choice can play an important role in that decision-making process. Materials affect many aspects of a product and firm--architecture, manufacture, and product performance. This paper examines the interrelationship of these early stage design choices through the application of process-based cost modeling. To capture the far-ranging effects of materials selection, models are presented which forecast the costs of development, manufacture, and assembly. A case study is detailed concerning two alternative material options for an automotive instrument panel beam: a conventional design (i.e., stamped steel) and a die-cast magnesium design which affords significant parts consolidation. Results indicate that parts consolidation led to both lower assembly and development costs. These cost reductions are shown to be a direct result of the consolidation of parts in the magnesium design.