603 オーステナイト系ステンレス鋼の塑性誘起マルテンサイト変態(材料のミクロ塑性)(OS.3 弾塑性材料のシミュレーションと実験)

概要

論文の詳細を見る
The present study proposes a method for the non-destructive detection of damage in an austenitic stainless steel SUS 304 by the use of martensitic phase transformation. Volume fraction of α martensite transformed in uniformly stretched SUS304 plates was measured and expressed as a function of the applied stress σ and/or strain ε. The distributions of α' phase in the wakes produced around center cracks were then electromagnetically measured in fatigued SUS 304 plates. The results were compared with the distributions of magnetic flux density B_z above the fatigue cracks in specimens magnetized by a strong permanent magnet. It was revealed that the B_z distributions reflected the α' phase distributions in the wakes: i.e., the distance between the points where B_z reached the maximum and the minimum 2l had a linear correlation with the fatigue crack length 2a and the maximum and the minimum values of B_z also had linear relations with the applied stress intensity factor range ΔK. These results imply that not only the crack length but also the fatigue damage can be detected in an electromagnetic non-destructive way.
2001-03-09