Chung Kyun Lee

Evaluation of solidification cracking susceptibility of Fe–18Mn–0·6C steel welds

Abstract Solidification cracking susceptibilities of high Mn steel welds were evaluated in the present study. A longitudinal Varestraint technique was utilised to assess the solidification cracking behaviours of the fusion zone. High Mn steel welds were more susceptible to solidification cracking than 304 and 202 austenitic stainless steel welds, however, they were less susceptible than 310S austenitic stainless steel welds. Extensive segregations of Mn and C took place at the dendritic and grain boundaries in the weld metal, and accordingly contributed to the increase of the hot cracking susceptibility of high Mn steel by the enlargement of solidification temperature range. Further, continuous γ-(Fe,Mn)3C eutectic phases formed at 1090°C along the grain boundary primarily resulted in the increase of solidification cracking sensitivity in high Mn steel.

A case of arteriovenous type cardiac hemangioma.

Cardiac hemangiomas are rare primary tumors of the heart and constitute only 2.8% of primary cardiac tumors. They are classified into capillary, cavernous, epitheloid and arteriovenous type and the last one is the most uncommon type. We experienced a case of cardiac hemangioma which was diagnosed as arteriovenous type for the first time in Korea in the literature. The patient was a 54-year-old woman who presented with palpitation and anterior chest pain. The diagnosis was based upon coronary angiography which showed two tumor blushings located in the interatrial and interventricular septum with venous drainage to the coronary sinus and right atrium. Associated atrial fibrillation with rapid ventricular response was controlled with digitalis.