Translating Knowledge into Super Clean Steels


ESR processESR process

In the Electro Slag Refining (ESR) process, a small pool of liquid metal solidifying beneath a layer of super heated slag, isolated from the environment is refined by absorption of inclusions and reduction in sulphur content.

Fast cooling conditions minimize segregation during solidification and carbides formed are finer. ESR steels remain free of defects like blow holes/shrinkage, internal and surface cracks, etc.

ESR steels produced at VA Innova Alloy Steeltech offer superior tool performance due to finer grain size, low inclusion level, better homogeneity and uniform carbide distribution.

ESRElectro Slag Refining

Electro Slag Refining is a process of refining metals using a molten slag that is electrically heated by resistance. The metal to be refined is in the form of an electrode, which is the product of more conventional processes like casting, rolling, or forging and this is held with its lower and submerged in a bath of molten slag contained in a water cooled mold. The metal droplets from the electrode fall through the slag and are collected in a metal pool below the slag bath. When they fall through the slag roplets get refined, and join the liquid metal pool which is continuously solidifying. This gives ESR the dual advantage: the refining operation which determines the compositions and cleanliness and the directional freezing which determines the structure of the ingot and has a considerable bearing on the properties of the product.

The solidified product is free from shrinkage defects, macro & micro segregation and has superior properties. Inclusions are removed from the metal and those left are usually very small and well dispersed.