INTEGRAL OR DIFFERENTIAL DESIGN FOR A COST EFFECTIVE COMPOSITE AUTOMOTIVE BODY STRUCTURE

Abstract

The business case needs to be improved in order to make carbon fibre composites useful for the automotive industry. It is often claimed that one of composite greatest advantages over metals is the ability to be manufactured in large complex integral geometries. By reducing the number of tools and avoiding or minimising the assembly processes, an integral solution is commonly seen as more cost effective. In high volume manufacturing these claimed advantages might be questioned. This paper presents an investigation of how complexity and size of a structure affect the manufacturing design choice between integral and differential design. The study is based on a conceptual cost model with a part cost and assembly module for carbon fibre composite manufacturing. The result shows that an integral design solution is not necessary the most cost effective option. Instead, dependent of the size and complexity of the part a divided structure may both minimise total material cost and tool cost.QC 20150410</p