Superplastic forming (SPF) is now considered a standard process in several industries including aerospace, rail and architecture. The ability to achieve large strains to failure in aluminum sheet alloys makes SPF an attractive option for the manufacture of complex three-dimensional panels in the automotive industry as well. However, the relatively slow cycle time and cost penalty associated with sheet alloys specially-processed to be suitable for superplastic forming has mostly limited this process to low-volume specialty vehicles. In order to achieve widespread usage in the automotive industry, the production volume for which SPF is cost-effective must be increased. This will require developments to reduce the material cost penalty as well as a variety of modifications to the manufacturing process that can decrease both the forming time as well as the overall process cycle time. While there is substantial literature on the superplastic characteristics of aluminum alloys, the bulk of this work is on materials that are typically cost-prohibitive and perhaps not appropriate for automotive applications. Additionally, there has been a limited amount of work done on developing superplastic forming as a manufacturing process addressing topics such as automation, lubrication, and pre and post forming technologies that serve to decrease overall component cycle time. One key to developing a cost-effective superplastic forming process for automotive applications is to adopt a systems approach where the integration of SPF into up and downstream operations is considered. This paper presents a perspective on the developments that are necessary to increase the production volume in which superplastic forming is cost competitive with traditional forming technologies.
展开▼
