Conveners
Session 1: ESR
- Alec Mitchell (university of british columbia)
Session 1: ESR 2
- Harald Holzgruber (INTECO melting and casting technologies GmbH)
Session 1: ESR 3
- Martin Detrois (National Energy Technology Laboratory)
Session 1: ESR 4
- Paul King (Ampere Scientific)
Evolution of Si concentration in 316 stainless steel electrodes was observed during a melting campaign consisting of recycling electroslag remelted (ESR) ingots to make new electrodes using vacuum induction melting (VIM). This campaign consisted of iterations of VIM + ESR operations to optimize melting parameters. The effect of Si content on the melt parameters and ingot quality was further...
coming soon...
ABSTRACT
Mathematical modelling studies of the remelt processes afford valuable insights into the solidification processes, but they generally present an instantaneous snapshot of conditions in the liquid pool rather than a global view of the entire process. This paper describes the development of simulators for the ESR (round and slab) and VAR remelt processes in different production...
ESR ingots of varying sizes -- 4”, 6” and 8” diameter laboratory scale ingots and commercial scale 20” diameter and 10”x42” slab ingots were produced using stabilized processes. Process control steps needed to stabilize the ESR process used to produce the laboratory 6” and 8” diameter ingots will be discussed, with attention to how the process was modified based on outcomes of employed trials....
It is generally believed that electroslag remelting can effectively reduce the number of large-size nonmetallic inclusions in steel and improve solidification structure, thus electroslag remelting (ESR) has become the main method to produce high quality die steel. However, large-size inclusions (D and Ds type) have been aperiodically detected in the production-scale ESR die steels. The...
This paper presents the results of laboratory and industrial scale investigations into the internal processes of electroslag remelting (ESR) facilitated by an external array of magnetic field sensors. Electroslag remelting is a crucial metallurgical process employed for the refinement and production of high-quality metal ingots, particularly in the context of alloy manufacturing. Real-time...
This paper investigates the effect of different electroslag remelting processes on the solidification quality and corrosion resistance of S136 steel. The results show that the double circuits process can reduce the mass fraction of oxygen in the ingot and effectively improve the cleanliness of the ingot. Analyzing the solidification quality of ingots, it can be seen that the secondary dendrite...
A martensitic stainless tool steel was remelted by a Pressure Electroslag Remelting (PESR) process with deliberate cancellation of the remelting just before normal hot-topping operation. Enabling evaluation of the ingots melt pool profile, dendrite angle and spacing, and macrosegregation during normal remelting conditions. A longitudinal cross section (500x500 mm) from the top of the 500 mm...
Non-metallic inclusions (NMI) are an essential quality criterion for electro-slag remelted products. Besides standardized testing methods such as ASTM E45, SEM-EDX-based methods have gained widespread application, as they provide not only information on shapes, sizes and numbers of NMI, but also about their chemical composition. Therefore, they are a useful tool not only for quality control...
Ni-based superalloy are sensitive to segregation during solidification and special care must be taken to control final chemistry on billet. Especially, some alloys are very sensitive to the formation of freckle type defect. Thus, the prediction of the evolution of the liquid phase composition and density during solidification is necessary to develop the corresponding melting conditions....
Modelling the Vacuum-Arc-Remelting (VAR) of NiFe-Based alloys like alloy 718 is motivated by its potential role in the further development of the process. It offers insight in the complex interaction of fluid mechanics and thermodynamics in a process which is experimentally hard to monitor. Nonetheless the numerical description itself requires a full definition of relevant boundary conditions...
The implementation of the feeding is a crucial and effective technique for preventing the accumulation of inclusions and the formation of shrinkage cavity at the top of electroslag ingot. In this study, a whole process model of electromagnetic-magnetic-flow-thermal inclusion removal with the full coupling of electroslag remelting of H13 die steel was established. The accuracy of the model was...
Several detailed models have been developed to account for the formation of freckles in conventional ingots, remelted ingots and in single crystal castings, accounting for the effect in titanium alloys, steels, superalloys and aluminium alloys as well as in model laboratory systems based on aqueous solutions or low melting point alloys. They are based on the concepts of inter-dendritic fluid...
An industrial scale experiment on the impacts of process variations on ingot quality of IN718 was carried out by monitoring the associated magnetic fields by VARmetric. The test performed monitored operational variations during the processing of the ingot when different arc gaps were maintained. A short, medium, long, and extra-long arc gap were chosen during the melt, the system was allowed...