Title: Development of Door Guard Beams Utilizing Ultra High Strength Steel
text: Door guard beams have been developed through the utilization of ultra high strength steel (tensile strength>100 kg/mm2). At first, the sheet metal gauge was reduced in proportion to the strength of the ultra high strength without changing the shape of the beam section. This caused beam buckling and did not meet guard beam specifications. Analyzing this phenomena in accordance with the buckling theory of thin plates, a design criteria that makes effective use of the advantages of ultra high strength was developed. As a result, our newly designed small vehicle door guard beams are 20% lighter and 26% thinner than conventional ones. This makes it possible to reduce door thickness while increasing interior volume.