The two companies commissioned the first vacuum arc remelting (VAR) plant in December 2024, with the second to follow in March 2025. The finished ingots from the first plant are already being processed, as ALD reports. With this new remelting plant, the steel producer is continuing to develop in order to meet the strong demand for stainless steel and nickel special alloys for the semiconductor industry. Further systems are to be integrated into the new plant over the coming years. ALD has already been a partner of Daido for decades and has made it possible to develop and market highly corrosion-resistant steels for semiconductors, as the Hanau-based company reported at the request of ViP.
A refining process takes place in a vacuum arc furnace in which the purity and solidification structure of ingots cast in air or in a vacuum induction furnace are improved. During the process, an electrode melts by means of an electric arc under vacuum and consumes itself in the process. The controlled energy input causes the ingot to grow at a controlled solidification rate in a water-cooled copper crucible. VAR remelted steel is very pure and has a homogeneous microstructure. The vacuum removes dissolved gases such as hydrogen, nitrogen and carbon, reduces unwanted trace elements with high vapor pressure and improves the oxidic purity.