Effect of Single Power Two Circuits Electroslag Remelting Process on the Ingot Solidification Quality

Abstract

The laboratory experiments have been carried out to investigate the effects of different power supply circuits on the solidification quality of GCr15 manufactured by the single‐power, two‐circuit electroslag remelting process. According to the previous research, the different power supply circuits are named as conventional electroslag remelting withdrawal process (ESRW), single power two circuits electroslag remelting process (ESR‐STCCM) with up power process (ESR‐STCCM‐U) and down power process (ESR‐STCCM‐D), respectively. The profile and depth of the molten pool, macroscopic and microscopic solidification structure, macrosegregation and microsegregation (macro‐/microsegregation) are analyzed. Compared with the ESRW process, ESR‐STCCM process can obtain a flatter and shallower molten pool. Besides, experimental and numerical results adequately prove ESR‐STCCM process can reduce the width of the mushy zone and the local solidification time (LST), therefore, the macro‐/microsegregation of segregation elements for ESR‐STCCM process are dramatically improved compared with ESRW process, especially for ESR‐STCCM‐D process.

Effect of Single Power Two Circuits Electroslag Remelting Process on the Cleanliness of the Remelted Ingot

“…According to the previous study, 36) the shape of the molten metal pool has a directly effect on the removal of inclusions. Figure 13 is the result of the sulfur print experiment for different remelting processes, it is clearly demonstrated that the depths of the molten metal pool for the different processes are 152 mm and 85 mm, and the shape of the molten metal pool for ESR-STCCM is flatter and shallower (The effect of the remelting processes on the shape of the molten metal pool had been deeply discussed in our previous study 19) ). Therefore, ESR-STCCM is beneficial to the float process of the inclusions.…”

“…The details of the remelting processes had been described in our previous study. 19) When the slag and air interface (slagsurface) was submerging the up mould (Φ333 mm) more than 40 mm, the withdrawing operation was started. The remelting parameters were shown in Table 2.…”

“…16,17) Besides, single power two circuits electroslag remelting process with current carrying mould (ESR-STCCM) had been proved to be an effective method to improve the ingot solidification quality. 18,19) The electromagnetic field, flow field, temperature field of the liquid slag pool and shape of the molten metal pool for ESR-STCCM were different from that of conventional ESR, therefore, the shape of the consumable electrode tip and the metal droplet size must be different. Hence, the remove non-metallic inclusions abilities for different remelting processes were no doubt different.…”

Effects of Nitrogen Gas Pressure on the Solidification Parameters and As-cast Microstructure Revolution during Pressurized Electroslag Remelting AISI 304 Stainless Steel

“…In addition, the sulfur print experiment (Baumann method) was executed to reveal the pool profile. 17) The samples with the dimension of 10 mm × 10 mm × 10 mm were taken from the other half of the ingot at a distance of 130 mm from the bottom. The microstructures were displayed with the Lichtenegger and Bloesch etchant (20 g NH 4 HF, 0.5 g K 2 S 2 O 5 and 100 ml H 2 O) at room temperature after the standard polishing techniques.…”

Refinement of Eutectic Carbides in M2 High Speed Steel by Adjusting Magnetic Flux Density During Magnetic Controlled ESR Process

“…Cao et al [23] proposed that the primary heat source for the metal pool during the ESR process is molten slag and remelting droplets, and that the Joule heat (temperature) distribution within the metal pool has a significant effect on its morphology. Due to the mold wall's water-cooling effect, the Joule heat in the slag/ metal pool was concentrated in the central area.…”