2426 一方向凝固超合金の結晶成長軸と直交する高温疲労荷重下における破断面の形成におよぼす不均質組織の影響(S13-3 高温材料・構造の強度と破壊(3),S13 高温材料・構造の強度と破壊)

概要

論文の詳細を見る
Directionally solidifired suprealloy has elongated grains aligned to the directionally solidified axis. Its anisotropic shape of grain boundary network may affect the fractography or the fatigue crack propatation rate. In order to clarify such an effect, fatigue tests are conducted with longitudinally or transversally loaded specimens. Crack surface types are classified into 3types according to the relative configuration of DS axis, normal axis of crack surface, and crack propagation direction. The transgranular crack (L-type crack under the longitudinal load) shows low crack propagation rate da/dN, while the intergranular crack (TL-type, with crack direction parrallel to the DS axis, subjected to the transversal load) shows high da/dN. The transversally loaded crack with crack direction parpendicular to the DS axis (TT-type) shows the conbined crack surface of transgranular and intergranular ones, and its da/dN is fluctuated in the midst of those in L- and TL types.
社団法人日本機械学会の論文
2007-09-07