The history of Outokumpu tracks back to a rich copper ore deposit that was discovered in Eastern Finland in 1910. Over the years Outokumpu, has evolved from a mining and multi-metal company to the global leader in stainless steel. Outokumpu as it is known today was formed through the acquisition of Avesta Sheffield in 2001 and Inoxum, the stainless steel arm of ThyssenKrupp, in 2012.

Outokumpu has a rich tradition in metals, and the company has been instrumental in developing the stainless steel industry into what it is today. Indeed the Group’s history is as old as that of stainless steel itself, dating back a century to Germany and the UK where stainless steel was invented more or less simultaneously in the beginning of the 1900s. Some years later, duplex stainless steel was invented in Sweden. The early research in these three countries marked the beginnings of Outokumpu’s stainless steel business.

Today, Outokumpu operates in all these regions where stainless steel was invented. In-depth technical expertise and R&D on metallurgy across stainless steel and high performance alloys forms a strong basis for Outokumpu’s competitiveness.

1910s–1920s: from `mystical hill` to the discovery of stainless steel

The start of Outokumpu was the discovery of a rich copper ore deposit (a `mystical hill` or ‘outo kumpu’ in Finnish) in a town called Kuusjärvi, nowadays also called Outokumpu, in Eastern Finland in 1910. A few years later, copper production started, first through a company owned by the Finnish state together with private parties and then as a wholly-owned state enterprise. In the first years, copper was smelted and refined in a small copper works right next to the mine. Even from the beginning there was enough copper for export as well. WW I, disagreements between the owners, financial difficulties and limited capital slowed down the start of operations. Nevertheless, by the late 1920s, the mine had become a modern mass production facility. The old copper works was closed in 1929, and Outokumpu began drafting plans for an integrated copper chain.

At the same time, in the 1910s, several discoveries in Britain, France, Germany and the United States led to the commercial development of stainless steel. In 1912, stainless steel was patented in Germany by Krupp, after discovery by Benno Strauss. In 1913, Harry Brearley discovered in his laboratory in Sheffield that a certain amount of chrome would stop steel from corroding. After these discoveries, stainless steel production started in Sheffield, UK and Krefeld, Germany. Actually some of the Outokumpu production locations are even older – the Dahlerbrück plant was first mentioned in the records in 1687.

1930s–1940s: major copper producer

Fast industrialization in Finland boosted Outokumpu operations. In 1932, Outokumpu became a limited company to ensure the development of its operations. In the beginning, the government still owned a majority of the company’s shares. Outokumpu was one of the five major copper producers in Europe. Outokumpu built an integrated copper chain in the 1930s by opening a new electric smelting plant – the largest of its kind in the world back then – and a metal works to refine raw copper. Outokumpu’s research and development lead to an invention of the flash smelting technique, which was the start of the Group’s technology division.

In the neighboring country of Sweden, duplex stainless steel was invented in 1930. By the 1940s, Outokumpu was a well known copper manufacturer. What the public didn’t know was that Outokumpu was already supplying some by-products such as iron to steel producers. The company made steel studies which resulted in a patented method to produce steel from the slag of copper production.

1950s–1960s: expanding into other metals

In 1950s and 1960s Outokumpu opened new nickel, zinc and copper mines and cobalt works in Finland and developed into a multi-metal company, refining ores from its own mines. It took innovation and determined R&D efforts to refine low-grade ores. Increased mining meant increased sales: starting from 1950, the company’s net sales increased tenfold by 1980.

Outokumpu was also looking into the possibility of producing steel. Major steps to that direction were the completion of its own nickel plant in Finland and, most importantly, the discovery of chromium ore: Finnish diver Martti Matilainen found pieces of chromium ore in a channel in Kemi in Northern Finland in 1959.

Outokumpu began to exploit the chrome deposit in Kemi in 1960 and built a ferrochrome smelter in nearby Tornio. Since chromium is what makes steel stainless and nickel makes it durable, the company now had access to the key raw materials of stainless steel.

1970s–1980s: multi-metal mining and technology company

In 1976, Outokumpu smelted its first steel in Tornio. The facility was one of the most efficient stainless steel factories in the world and the only one to be backward integrated, with the company’s own chrome mine in the neighboring town of Kemi and ferrochrome operations at the same site. At first Tornio produced 50 000 tonnes of stainless steel per year, which constituted Outokumpu’s entire capacity in stainless steel. Later hot- and cold-rolling mills completed the integrated mill and allowed Outokumpu to expand its product portfolio.

As Outokumpu began to exhaust its ore resources in Finland, the answer was international expansion and growth through acquisitions, such as the Tara zinc mine in Ireland, the Viscaria copper mine in Sweden and semi-product facilities in Spain, Sweden and USA. Outokumpu also utilized the technology it had invented in its own mines and plants and sold this technical know-how to other producers. In 1980s, for example, a significant number of the copper and ferrochrome smelting plants worldwide used technology developed by Outokumpu. The Group became a publicly listed company when its shares were listed on the Helsinki stock exchange in 1988.

1990s–2000s: focus on stainless steel

At the turn of the millennium, Outokumpu was a multi-metal and mining company with a global raw material base and 21 000 professionals around the world. In 2000 the Group made a decision to focus on stainless steel, double those operations and eventually sell its other operations. That same year Outokumpu and renowned stainless steel company Avesta Sheffield announced that they would combine their stainless steel operations under the name of AvestaPolarit. The company became the second largest stainless steel producer in the world. Slightly ahead of it was newly combined German ThyssenKrupp, also a combination of two major stainless steel companies, Thyssen and Krupp.

The Avesta Sheffield deal brought more specialty stainless grades, including the Swedish innovation of duplex, to Outokumpu`s product portfolio. Outokumpu now produced 1.8 million tonnes of stainless steel per year. That was a turning point for a multi-metal company who now focused on stainless steel and exited from other metals, mining and technology in the 2000s.

2010s: a new global leader in advanced materials

In 2012, Outokumpu became the global leader in stainless steel and high performance alloys, when it acquired Inoxum GmbH, the stainless steel arm of ThyssenKrupp. Outokumpu companies are the inventors of stainless steel, and the Group still operates in countries which were instrumental in its discovery.

Outokumpu boasts the widest product portfolio in the market, cost-efficient and modern mills, its own chrome mine and 100 years of expertise in metals and advanced materials.

Outokumpu Stainless Downloads

Austenitic, Cr-Ni-Mo Alloyed Stainless Steel Grades

410L 4003 - Brochure

410S 4000 Brochure

434 4113 Brochure

Duplex, Austenitic - Ferritic