rapid crack progressとは 意味・読み方・使い方

To provide a method for welding an automobile wheel, a method that prevents a crack from generating from the starting and completing ends of a weld bead, without thickening a rim plate and without performing an additional process, that holds the shearing strength of the rim and the disk, and that makes rapid progress in the improvement of durability.例文帳に追加

リムの板厚を厚くすることなく、また、付加的工程を行うことなく、溶接のビードの始端部、終端部からの亀裂の発生を防止し、リムとディスクの剪断強度を維持し、耐久強度を飛躍的に向上させた自動車用ホイールの溶接方法の提供。 - 特許庁