Orkla Exolon A/S & CO was formally established June 4,1962. It was a joined venture between Orkla Grube-Aktiebolag, Christiania Spigerverk and The Exolon Company.
In the early sixties, Orkla Grube-Aktiebolag was undertaking a large re-organization of its mining and melting industry. New projects were created to reduce the impact the re-organization would have on the local labour market.
The first contact between The Exolon Company and Orkla Grube-aktiebolag was established in May of 1960, and during the same autumn a pilot study on a silicon carbide plant was initiated. The decision to build the silicon carbide plant was made in September 1961 with construction beginning on December 11th of the same year. In 1963 the processing plant began to operate with crude from the Exolon Company.
The Furnace plant was completed and ready to make its own crude on December 27, 1963 with expansions planned for 1965, 1970 and 1971. The silicon carbide industry was established with employees that carried with them a long tradition from the mining industry in Orkdal.
In 1982 Elkem, previously called Christiania Spigerverk, ended its business relationship, thus changing the ownership structure. The company operated as a 50/50 partnership between Orkla ASA and The Exolon Company. The Exolon Company was later bought by Washington Mills.
In August 2004, Washington Mills Co. purchased 100% of the company and still retains 100% of the company today. In February 2008, the business changed its name from Orkla Exolon AS to Washington Mills AS.