1955 年 41 巻 8 号 p. 881-886
The steel products of Japan have contained more Cu than the mported products due to their raw materials, and after the War II that tendency has been especially remarkable. The authors studied the effects of Cu on the silicon-manganese spring steel, systematically, with the samples industrially produced. The results of the present paper concerning the hot properties were as follows:
1) Cu has scarcely affected on the growth of austenite grains.
2) On the eye-back work in the manufacturing of the springs, the temperature of generating the cracks lowered as the Cu content increased.
3) In the hot-tensile test, Cu increased slightly the tensile strength and the yield point of the steel but decreased very fairly the elongation and the reduction of area.
4) In the hot-impact test, the increase of Cu content promoted the brittleness of the steel at high temperatures.
5) The resistances to the deformation measured by the drop-weight method increased slightly with Cu.