球状黒鉛鋳鉄の低サイクル疲労寿命に及ぼす黒鉛粒径の影響

概要

論文の詳細を見る
In this paper, the effect of average graphite diameter on low cycle fatigue life was investigated in spheroidal graphite cast irons involving the same volume of graphite. Three kinds of average graphite diameter D_m were used (D_m=16.5μm ; SGD, D_m=31.1μm ; MGD, D_m=42.7μm ; LGD). Low cycle fatigue tests were carried out using cylindrical specimens. As a result, it was clear that the difference of fatigue life was small as comparison with the difference of average graphite diameter. That is, the fatigue life in SGD is 1.5 times as long as that in other cast irons, though average graphite diameter in SGD is about one third smaller than that in LGD. These results can be explained by three factors controlling fatigue life that we proposed. The cause of increase of fatigue life in SGD is that the crack initiation length in SGD is shorter than that in other cast irons. The crack initiation length depends on the microshrinkage size or dross size, not depending on average graphite diameter.
一般社団法人日本機械学会の論文
1998-09-25