The program of reconstruction work that accompanied the start of production at the Salzgitter plant extended over many years. In April 1954 the commissioning of a new heavy and medium plate mill marked the first time in nine years since the end of the War that the plant was capable of end-to-end production from pig iron to plate.
Other urgently needed installations followed despite the difficulties in financing the high investment costs which put a heavy strain on the company and the group to which it belonged. It was essential to forge links with competitors in Germany and abroad who had been able to recommence production far earlier than the steelworks in Salzgitter. An important step was taken in 1960 with the decision to build both a wide hot strip mill and a cold mill, thereby aligning the plant’s fortunes with the rapidly growing demand for flat rolled steel products.
In the post-War era the AG für Berg- und Hüttenbetriebe, of which Hüttenwerk Salzgitter AG was a subsidiary, developed into a broadly diversified coal and steel conglomerate. In 1961 it changed its name to Salzgitter AG, and in 1964 the steelworks was duly renamed Salzgitter Hüttenwerk AG.
As long ago as the 1950s the iron and steel works in Salzgitter had gradually resumed its cooperation with the neighboring Ilseder Hütte. From the beginning of the 1960s the two companies jointly operated a wire mill at the Salzgitter site. And when economic developments in the steel industry prompted a general trend towards joint ventures and mergers, Ilseder Hütte was not merely the geographically closest partner.
As a result of the intensive discussions that took place from the mid 1960s onwards, the Salzgitter Group ultimately folded its Steel Division amalgamated within Salzgitter Hüttenwerk AG – in other words, primarily the plant in Salzgitter – along with certain other related interests into Ilseder Hütte as part of an increase in capital. In turn Salzgitter AG acquired a majority stake in the new joint undertaking which on October 1, 1970 was renamed Stahlwerke Peine-Salzgitter AG.