Abstract
In the earlier work1) on the fatigue strength of spheroidal graphite cast iron, the author has shown that the presence of wormlike graphite and inclusions may lower the fatigue strength of the cast iron. To confirm the influence of these two microstructural components, fatigue tests were carried out on the test specimens which contained different amounts of wormlike graphite and nonmetallic inclussions.
The fatigue limit decreases in proportion to the amount of wormlike graphite. Inclusions remarkably lower the fatigue limit, especially at high matrix hardness. When the inclusions and wormlike graphite are present at the same time, the fatigue limit is decreased because of the added effect.
