STUDY OF THE WATCH-SPRING MATERIAL
1951 Volume 37 Issue 10 Pages 524-527
Details
1951 Volume 37 Issue 10 Pages 524-527
The "Metal Progress" 1948 (P. 648) reported that the fatigue limit is improved by the "martemper and temper."
It seems to differ from the "martemper" called in our country, but it means to bold an object for a time at a temperature just above Ar" transformation and to cool it gradually in this critical range of the Ar" transformation and temper.
The fact that the fatigue limit is improved by the "martemper and temper" is probably due to being free from the microcrack by quenching, but its problem has not been solved yet. The authors reported the comparison of the mechanical properties in the martemper and temper, the austemper, and the oil quenching and temper on the hardness, the tensile strength, the elongation, the fatigue limit and the simple torque test.
