中炭素鋼の温間加工材強度におよぼす各種強化要因の影響

抄録

The purpose of this research is to clarify the effects of strengthening factors on tensile strength of warm-worked middle carbon steels. The increase in the tensile strength of warm-worked products is realizable by increasing tensile strength of steel before warm-working and work hardening by warm-working. As a strengthening method of warm-worked products by material strengthening, solid solution hardening is effective. Specifically, addition of Si is effective. As a strengthening method of warm-worked products by work hardening, low-temperature working is effective. Also the addition of elements such as Cr which inhibits the annihilation of dislocations can strengthen warm-worked products through increasing work hardening. Material strengthening by decreasing cementite spacing, etc. is less effective in strengthening of warm-worked products. This is by that plate-like cementites are changed to granular ones by warm-working.