Development of High Strength Steel Sheets and Practical Application to Autobody Parts

The practical application of high strength steel sheets to autobody parts has been increased year by year in order to promote weight reduction and ensuring safety. New types of high strength steels with good formability have been developed and the average weight ratio of high strength steel in a whitebody is over 20 % in Japan. In the near future the weight ratio of high strength steel in a whitebody is estimated as over 40 %. In the forming of high strength steel sheets it is difficult to suppress geometrical failures and dimensional inaccuracy. The developments of forming techniques and their suitable application are required to succeed the forming of high strength steel sheets.