This study focused on the effect of ELECTROSLAG REMELTING process (ESR) on microstructure and composition of as-cast Cu-Cr-Zr alloy. The results revealed that applying ESR process resulted in a more uniform distribution of alloying elements. However, slight aggregation of large precipitates and inclusions existed in as-cast ingot. It was observed that impurities like P, S and Mg which had significant effect on electrical property were eliminated after ESR process. Moreover, further optimization of alloy composition which in turn would affect its mechanical and electrical properties was obtained through using ESR technique, successfully.

In recent years, the push to reduce fuel consumption and emissions in turbines, designs have focused on achieving higher operating temperatures, which require materials capable of sustaining elevated temperatures in industrial applications. The development and production of the nickel-base superalloy VDM780, with an operating temperature above 750 °C (nominally 780 °C), have been pursued to meet this demand. This superalloy is often considered a suitable alternative to Inconel 718. The present study demonstrates the thermomechanical processing can significantly accelerate homogenization, enabling the production of a wrought structure in VDM780 with minimal heat treatment. A cast ingot of the VDM780 superalloy was first prepared using a vacuum induction melting (VIM) furnace, without employing refining processes such as ELECTROSLAG REMELTING (ESR) or vacuum arc REMELTING (VAR). The conditions for homogenization and hot rolling were then investigated using simultaneous thermal analysis (STA). The results show that a homogenization temperature of 1160 °C provides adequate homogenization, resulting in a microstructure that is well-suited for workability.

A molecular dynamics simulation study has been performed to investigate the solidification and REMELTING of aluminum using Sutton-Chen many body potential. Different numbers of atoms from 108 to 2048 atoms were considered to find an adequate size for the system. Three different cooling and heating rates, i.e. 1012 K/s, 1013 K/s and 1014 K/s, were used. The structure of the system was examined using radial distribution function. The melting and crystallization temperatures of aluminum were evaluated by calculating the variation of heat capacity during the phase transformation. Additionally, Wendt–Abraham parameters were calculated to determine the glass transition temperature. It is shown that the melting temperature of aluminum increases as the heating rate increases. During solidification, a crystalline or amorphous-like structure is formed depending on the cooling rate. REMELTING of the amorphous solidified material is accompanied by crystallization before melting at heating rates<1014 K/s. The melting temperature also depends on the degree of structural crystallinity before REMELTING.

In this research, the influence of chemical composition of slags and the melting rate on the impurity of commercial grade iron in ESR processing has been investigated. The chemical composition and microstructure studies were evaluated, using spectrophotometer, OM and EDX analyses attached to SEM.The results show that ESR process has successfully reduced the amount and size of inclusions. In some case, sulfide inclusions were not observed and the size of other inclusions was reduced down to 10µm, whereas in primary electrodes the size of inclusion was up to 100µm. An increase in the slag basicity up to a critical point and a decrease in the melting rate caused better desulfurization ability of the slags. However, the increase in the time of process was governed by the melt temperature and fluidity.

transition and heat affected zones formed during surface REMELTING (in order to improve wear resistance) with TIG process has been investigated. Relationship between various TIG parameters and thickness of remelted and heat affected zones revealed that a high concentrated heat energy is imposed by TIG process which makes it a proper option for focused surface treatment. Based on micro structural examinations five areas with different microstructure and micro hardness were identified within the surface area. Graphite flakes were totally dissolved within the first area leading to the transformation of denderitic austenite to plate marten site and the formation of ledeburite within interdenderites. The main feature of the second area, resulted from the presence of graphite flakes, was the local melting with a gap in the vicinity of graphite flakes and that of third area was the formation of finer and denser marten site plates closer to the graphite flakes compared with those formed at a further distance. In the fourth layer there is a mixture of martensitic and pearlitic matrix while the matrix of fifth layer has no change of microstructure.In this study the effect of graphite flakes present in a pearlitic grey cast iron on the microstructure of melted.