試作した衝撃ねじり試験機とそれによる二,三の低温ねじり試験結果について

概要

論文の詳細を見る
The present investigation was carried out for the size effects of test piece and various testing conditions on the torsional fracture behaviour, using a newly developed dynamic torsion machine. Dynamic torque-twist curves were obtained photographically at various temperatures. The maximum rate of straining was 60 per second and the range of temperatures from +200℃ to -196℃. Yield and fracture strength and plastic strain to fracture were not affected by the variation of gauge length of the test piece, but yield and fracture strength increased with decreasing of the diameter. The size effects on torsional strength were also appeared for hollowed specimens as well as for solid ones. In the static torsion test, fracture type at comparatively low temperature had a ductile manner and the cleavege fracture appeared only at -196℃ under the tested conditions. On the other hand, in the dynamic test, the specimens used for the investigation took a ductile fracture, excepting a specimen having larger grain than the A.S.T.M. No 4. The torque-twist curves in static test or room temperature dynamic test dropped at maximum torque after drop in load. To the contrary, in the low temperature dynamic test, after reaching the maximum stress, torque suddenly decreased with increasing twist angle and then kept a constant value until the beginning of fracture. Ruptured specimen with cleavage type due to the dynamic torsion test had been broken at maximum torque. These strange phenomena in the fracture manners and the torque-twist curves were discussed and assumed to be due to the temperature rise in the tested part connected with the rapid large plastic deformation.
社団法人日本材料学会の論文
1963-06-15

試作した衝撃ねじり試験機とそれによる二,三の低温ねじり試験結果について

スポンサーリンク

概要

著者

関連論文

スポンサーリンク