| Title |
The matrix Structures of Spheroidal Graphite Cast Iron and the High cycle Fatigue Properties |
| Authors |
김창주(Chang Joo Kim); 윤한상(Han Sang Yoon) |
| Abstract |
The rotary bending and the tension-compression fatigue tests were performed on as-cast spheroidal graphite cast iron as well as heat treated spheroidal graphite cast irons with three different matrices: ferritic, pearlitic and ferrite-pearlitic. The fatigue limit of the ferrite-pearlitic specimen was higher than that of the pearlitic or the ferritic specimen. It was shown that the fatigue limit was affected by the matrix structures as well as the static strength. The stress intensity factor K, was higher than the notch factor K, in the ferritic specimen. The sensitivity to K of the ferritic spheroidal graphite cast iron was higher than that of the steel with the same tensile strength. The result was attributed to the notch effect of graphite nodules in the matrix |