Why is Electro-slag Remelting (ESR) process important for knife quality?
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Author : Mr. Jiang
Update time : 2021-07-02 11:58:21
Electro-slag Remelting, or ESR for short, is the most widely used secondary refining metallurgical technology in the world today, mainly used in the production of special steel and alloys.
First, a series of physical and chemical reactions occur between molten steel and molten slag, which can remove harmful impurity elements (especially sulfur removal) and non-metallic inclusions.
Secondly, since the melting of the electrode and the crystallization of the molten metal proceed at the same time, during the gradual solidification of the steel ingot, there is always a molten pool of liquid metal and a heated slag pool at the upper end, which not only keeps heat but also has enough liquid metal to fill the solidification process. The shrinkage cavity caused by shrinkage can effectively eliminate the common porosity and shrinkage cavity of general steel ingots. At the same time, the gas and inclusions in the molten metal are also easy to float, so the structure of the steel ingot is dense and uniform.
At the same time, the steel ingot gradually solidifies from bottom to top, and the slag pool and the molten metal pool move upward continuously. The rising slag pool forms a layer of slag shell between the inner wall of the mold and the steel ingot, which not only makes the surface of the steel ingot smooth and clean, but also reduces the heat conduction in radial direction, which is conducive to sequential crystallization from bottom to top and improves the crystal structure inside the steel ingot. Sequential crystallization greatly reduces the segregation caused by the simultaneous solidification of a large amount of molten steel in the traditional casting method.
Moreover, the entire process of electro-slag remelting is always carried out under the liquid slag layer, which is isolated from the atmosphere, which minimizes the pollution of the atmosphere to the molten steel, and reduces the increase in hydro-gen and nitrogen and the secondary oxidation of the molten steel.
Since the steel is further purified and the crystal structure of the steel ingot is improved on the basis of the primary refining, electro-slag remelting is used in the production of the raw material of the knives from GOODKLIFE, which greatly improves the strength and toughness of the shearing tool.
First, a series of physical and chemical reactions occur between molten steel and molten slag, which can remove harmful impurity elements (especially sulfur removal) and non-metallic inclusions.
Secondly, since the melting of the electrode and the crystallization of the molten metal proceed at the same time, during the gradual solidification of the steel ingot, there is always a molten pool of liquid metal and a heated slag pool at the upper end, which not only keeps heat but also has enough liquid metal to fill the solidification process. The shrinkage cavity caused by shrinkage can effectively eliminate the common porosity and shrinkage cavity of general steel ingots. At the same time, the gas and inclusions in the molten metal are also easy to float, so the structure of the steel ingot is dense and uniform.
At the same time, the steel ingot gradually solidifies from bottom to top, and the slag pool and the molten metal pool move upward continuously. The rising slag pool forms a layer of slag shell between the inner wall of the mold and the steel ingot, which not only makes the surface of the steel ingot smooth and clean, but also reduces the heat conduction in radial direction, which is conducive to sequential crystallization from bottom to top and improves the crystal structure inside the steel ingot. Sequential crystallization greatly reduces the segregation caused by the simultaneous solidification of a large amount of molten steel in the traditional casting method.
Moreover, the entire process of electro-slag remelting is always carried out under the liquid slag layer, which is isolated from the atmosphere, which minimizes the pollution of the atmosphere to the molten steel, and reduces the increase in hydro-gen and nitrogen and the secondary oxidation of the molten steel.
Since the steel is further purified and the crystal structure of the steel ingot is improved on the basis of the primary refining, electro-slag remelting is used in the production of the raw material of the knives from GOODKLIFE, which greatly improves the strength and toughness of the shearing tool.
Goodklife Electro-slag Remelting Plant
