Chapter 4 Comparison of Advanced High-Strength Steels with Alternative Materials

Advanced high-strength steels (AHSS) are a family of steels that are stronger than most steels and have better formability than today’s conventional high-strength steels. New U.S. safety and fuel economy regulations have intensified pressure on OEMs to reduce vehicle weight. These pressures are causing auto companies to rethink alternative material applications and to look for opportunities that steel offers. The purpose of this book is to provide information for engineers who are designing the next generation of lighter vehicles. The material in the book is presented to help them make informed decisions on what basic materials to use and how to optimize those materials to achieve cost-effective weight reduction. The emphasis is on steels in general and AHSS in particular. However, there is much information on comparisons of steel with alternative materials for different subsystems of the vehicle. To support the latest automotive challenges in terms of weight reduction, this book lays out the opportunities for alternative material use in automobiles and offers the most up-to-date design guidance in efficient architectures that use AHSS. It simultaneously explores weight savings and resulting fuel economy advantages of a strategic usage of AHSS. Realistic comparisons with other alternative materials are made through detailed analyses. It also offers test cases that demonstrate how AHSS technology has developed. The focus of the text is on body and chassis structures and the sheet metal of which these systems are primarily made. More of the content addresses the automotive body, as this is where most of the AHSS are being applied today. The past, present, and future of AHSS are covered, as well as competing technologies such as aluminum sheet metal.