Critical Temperature Range in Standard and Ni-bearing Spheroidal Graphite Cast Irons

Abstract

Describing the conditions for reaustenitization of spheroidal graphite cast irons is of interest for their heat-treatment after casting, e.g. for manufacturing austempered ductile irons. Differential thermal analysis has been used to characterize the direct eutectoid transformation and the reverse transformation, i.e. the reaustenitization. This has been applied to a standard and a Ni-bearing alloy, with a ferritic matrix for the former, both a ferritic and a pearlitic matrix for the latter. The results are discussed in relation with the stable and metastable three phase fields. While earlier description of the direct eutectoid transformation is confirmed, the one for reverse eutectoid has been found more complex and is amended.

Lowest Fatigue Limit Estimation of Ductile Cast Iron Joints by Considering Maximum Defect Size Toward Replacing Welded Joints

“…Ductile cast iron (DCI) 1,2) has attracted attention as a material that can replace welded joints. 3) In our previous experimental study, the authors revealed that the fatigue strength of DCI joints is about 2 times or more larger than that of non-load-carrying cruciform welded joints.…”