Quality of the Large ESR Ingots and Products from Them
1976 Volume 62 Issue 13 Pages 1698-1707
Details
1976 Volume 62 Issue 13 Pages 1698-1707
In order to evaluate the metallurgical homogeneity of large ESR ingots, longitudinal cross sections of the 1 500 mm∅ remelted ingots were examined by metallurgical method, and also the influence of the ESR melting rate was investigated. Furthermore, to confirm the quality of the ESR ingots, some experiments in the application of ESR process of turbine parts were carried out.
The results are as follows:
(1) Freckles and equiaxial crystal are observed at the top portion of a 1500mm∅ ESR ingot with 2000kg/hr melting rate. The defects are reduced by decreasing the melting rate.
(2) It is suggested that the formation of freckles may be related to distance between solidus and liquidus lines.
(3) From the attempt of manufacturing the turbine parts by the ESR process, superior characteristic of homogeneity and mechanical properties are obtained.
