Abstract
This paper presents the results of compressive fatigue and creep tests on piano wire coiled spring, setting-treated at elevated temperature conditions. The specimen is treated for 4min at a temperature of 250°C under the compressive load of 40kg, for this condition gives the material the highest values of proportional limit and spring constant.
The results obtained are as follows;
(1) The fatigue limit of setting-treated spring is about 14% higher than the conventional bluing-treated one.
(2) The value of deformation limit is nearly constant for the value of τa/τm from 0.6 to 1.0, while it becomes higher as the value of τa/τm becomes lower.
