FATIGUE DESTRUCTION EVALUATION TECHNIQUE OF POLYCRYSTALLINE METAL AND FATIGUE DESTRUCTION EVALUATION DEVICE

• Main Authors: OKADA HITOSHI, OSHINO HIROMASA, TAKAHASHI KOTOMI, SAKAKIBARA YOHEI, KUBUSHIRO KEIJI
• Format: Patent
• Language: English; Japanese
• Published: 13.12.2018
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

To properly evaluate the fatigue destruction of a bimodal organization having needle crystals.SOLUTION: A fatigue destruction evaluation technique of a polycrystalline metal body having a bimodal organization including needle crystals has: a crystal orientation specifying process for acquiring crystal orientations of the needle crystals in a plurality of measurement points on the basis of a characteristic of a rear scatter of an electron beam irradiated to the polycrystalline metal body; an orientation difference calculation process for calculating an orientation difference between the different measurement points on the basis of line profiles which are drawn on the measurement points of the needle crystals; and an orientation expansion coefficient estimation process for estimating a stress expansion coefficient on the basis of the orientation difference.SELECTED DRAWING: Figure 1 【課題】針状結晶を有するバイモーダル組織において、疲労破壊評価を適切に実施する。【解決手段】針状結晶を含むバイモーダル組織を有する多結晶金属体の疲労破壊評価手法であって、上記多結晶金属体に照射された電子線の後方散乱の特性に基づいて複数の測定点において針状結晶の結晶方位を求める結晶方位特定工程と、上記針状結晶の測定点上に引かれたラインプロファイルに基づいて異なる測定点同士の方位差を算出する方位差算出工程と、上記方位差に基づいて応力拡大係数を推定する応力拡大係数推定工程とを有する。【選択図】図１