カテーテルの座屈挙動に関する研究

（含水条件下での断面内の扁平化現象の発生領域について）

抄録

This paper describes the relation between the flattening phenomenon in the cross section and the visco-plastic behavior in the catheter made of soft nylon resin reinforced with thin stainless wires. In particular, the flattening phenomenon occurs when the torsional moment is applied after axial load. Therefore, in this study, the occurrence region of the flattening phenomenon is examined based on the visco-plastic theory. In consideration of the shape of cross section gradually changing into the elliptical shape during the process of applying the torsional moment, the experimental equation for the torsional moment is derived based on the shear flow theory for determining the occurrence region of flattening phenomenon. Especially, in the present study, considering actual usage conditions of the catheter, the experiments are conducted in water condition and non-water condition.