Second to steel, aluminium is the most widely used metal and its applications are manifold. It is available in all forms; such is wire, bars, extrusions, power, forging and casting. One of the major characteristics of aluminium is that it is very well suited for recycling. Recycled aluminium is known as secondary aluminium, but maintains the same physical properties as primary aluminium.

 The Company XY is a cast house in the Nordic countries supplying aluminium cast products. Customers today are placing greater demands on the products strength and quality. An important quality parameter of aluminium is its purity from contaminants, where hydrogen is one of the major issues with impact on the strength of the final product.

 The hydrogen content has been measured by Density Index for two different types of alloys (EN AB-43400 and EN AB-46000), at specific locations, at different stages in the process and with different degassing methods. Density Index is a measure for measuring and comparing the samples with respect to the internal porosity. As the air contains moisture, along with the melt temperature, the solubility of hydrogen in the melt is affected.

 The project work has focused on reducing the hydrogen content and to improve the strength of the final product.