On 9 December 1949, the pioneering decision was taken in Linz, Austria, to construct a steel mill based on a completely new technology, the Linz-Donawitz process (LD process). Just three years later, on 27 November 1952, the world’s first LD steel mill went into production at the site of voestalpine AG’s current headquarters. This was closely followed by a second mill, opening on 22 May 1953 in Donawitz. The LD process was one of the century’s most significant industrial inventions, revolutionizing the global steel industry at a stroke. It established the voestalpine Group as a leading metallurgical company and formed the basis for the Group’s subsequent and consistent technological and qualitative developments as a global player.

The voestalpine Stahlwelt in Linz is currently hosting a special exhibition on 60 years of the LD process, showing how this innovation has changed the world. The exhibition runs until the end of the year and entrance is free.

Steel is the world’s most commonly used construction material. Steel is found almost everywhere and has played a key role in creating the preconditions for modern mobility, efficient energy production and contemporary urban development. The invention of the LD process in Linz and Donawitz was certainly one of the ground-breaking discoveries which changed the entire steel industry 60 years ago and made this development possible. This breakthrough enabled significantly more steel, of a better quality, to be produced in a shorter time and much more economically. This opened up a completely new range of opportunities for two young companies, the Vereinigte Österreichische Eisen- und Stahlwerke Aktiengesellschaft in Linz and the Oesterreichisch-Alpine Montangesellschaft in Donawitz. Almost no other invention has had such an impact on economic growth globally. The willingness to accept the large risk involved in taking these decisions is worthy of our greatest respect, but above all it was the courage and spirit of innovation represented by this new process, rather than reliance on tried and tested methods, which is impressive.

70 percent of global steel produced using the LD process

Today, more than two-thirds of the world’s steel is produced using the LD process. Invented 60 years ago, it remains the global production standard. This makes steel, a 100% recyclable construction material and of equal quality when recycled, an important driver of the global economy. Of the 1.5 billion tons of steel produced globally in 2011, at least one billion was produced using LD process-based technologies.

The clear strategic focus on the latest technologies and most demanding quality products, as well as a value chain which is longer and more comprehensive than those of all our competitors, will remain our strategy for the coming years. "The Group will continue to actively expand its research and development capacities and position itself even more strongly as a global technology pioneer, especially in the mobility and energy sectors", Eder declares.

Expenditure on research and development for the business year 2012/13 reflects this drive, increasing to the record level of €132 million. Despite the global economic crisis and economy drives, over the past ten years expenditure in this key area has grown by an average of 11% annually. There will be a further increase during the coming business year.

The LD process in detail

The Linz-Donawitz process (LD process) is a steel production process in which oxygen is blown through carbon-rich pig iron, converting it to low-carbon steel. During the LD process a refractory-lined container, a so-called LD converter (or ladle) is loaded with molten pig iron and a coolant (scrap or sponge iron). Then a water-cooled lance is used to blow pure oxygen over the molten iron smelt. During this "freshening" process, the content of tramp elements – carbon, silicon, manganese, sulfur and phosphorus – is continually reduced. Depending upon the type of steel being produced, after freshening, alloying elements can be added. The steel is then poured into a ladle (tapping) at a temperature of around 1650°C. As with so many inventions, as well as the spirit of innovation, persistence and courage, chance has also played a role in discovery of the LD process: after international experiments in adding oxygen to pig iron in the 1930’s were unsuccessful, similar experiments were also started in Linz’s steel mill at the end of the 1940’s. It was planned to blow the oxygen directly into the molten pig iron. However, one of the feeding pipes was faulty. Consequently, oxygen escaped and was blown directly onto the surface of the liquid iron smelt. This was sufficient to significantly improve the purity of the produced steel, and the characteristics of the LD process were established.