The Effects of Interstitial Solute Elements on the Fatigue Limit Behavior of Titanium

摘要

The fatigue behavior of titanium and three titanium-interstitial alloys, each containing about 1/4% of C, N, orO, has been investigated through the temperature range of 70F to + 500F and at liquid nitrogen temperature. The fatigue limit stress was found to vary with temperature in a more or less consistent fashion depending on the interstitial type and total interstitial content. The position of the fatigue limit knee does not vary in a consistent fashion with temperature, since the rate of strain aging, the process which is believed to be responsible for the fatigue limit, depends both on the temperature and the type of interstitial involved. It was found that the small amounts of the interstitials listed above cause marked changes in the fatigue limit stress. The effect of carbon seems to be the most pronounced insofar as strain aging is concerned, but the nitrogen alloy was far stronger at every temperature investigated. (Author)