抄録
Effects of prior cold drawing on the mechanical properties of 0.8%C steel, patented, cold drawn and then low temperature annealed, has been studied by tensile tests, torsion tests, Charpy impact tests and fatigue tests.
The results of tensile tests after patenting show that specimens cold drawn prior to patenting (Specimen B) are stronger than those which were not cold drawn prior to patenting (Specimen A). Also, the pearlitic structure of specimen B is finer than that of specimen A. The austenite grain size of specimen A is larger than that of specimen B.
After patenting, the specimens were cold drawn and low temperature annealed at 100°∼640°C. Specimen B is stronger than specimen A after these treatments as well as after patenting. Elongation and reduction in area of specimen A are larger than those of specimen B, but the number of torsion of specimen B is smaller than that of specimen A.
Charpy impact results show that the absorbed energy of specimen B is larger than that of specimen A when both specimens were annealed at temperatures between room temperature and 250°C, but, when they were annealed at 300°∼400°C, this tendency becomes reversed.
