最大介在物寸法の推定法とそれに基づく高速度工具鋼の疲労限度の予測

概要

論文の詳細を見る
The fatigue fracture surface of high strength steels often shows a typical mark like fish-eye. A nonmetallic inclusion is commonly found at the center of fish-eye mark. This implies that the nonmetallic inclusion at the center of fish-eye of a specimen fractured by tension-compression fatigue test is the maximum one existing in the specimen. It was confirmed, from the eperiments on many sample of a high-speed steel, that the size (the square root of projected area: √<area>) of the nonmetallic inclusions af fish-eye followed the statistics of extreme values. Moreover, it was found that the fatigue fracture stress at these inclusions could be predicted by Murakami et al's equation which was proposed on the basis of fatigue data on small artificial defects. The lower limit of a large scatter band of the fatigue strength was also predicted by combining the statistical distribution of extreme values of √<area> and Murakami et al's equation. It was shown that the prediction was in good agreement with the experimental results.
社団法人日本材料学会の論文
1989-10-15