The quality of the recovered matrix material as an element of assessment of effectiveness of the composite recycling process

Metal composites are ever more readily used as structural materials, due to their properties. Therefore, in spite of their difficult processing, their use constantly grows (e.g. SGL Carbon Poland S.A.). In consequence, the amount of their wastes grows too. Since the social pressure aimed at improving the quality of environment has recently intensified and the significance of the technologies enabling recovery of secondary materials has increased, the interest in recycling of metal composites also grew, irrespective of all the difficulties related thereto. One of the groups of metal composites includes the composites with saturated reinforcement. They may be recycled only with the method of components separation. The simplest way for this consists in choosing an appropriate environment in which the recycling occurs so as to enable free outflow of melted matrix from capillaries of the porous reinforcing profile. As an effectiveness measure of the process not only the yield of the melted metal but also its quality should be considered. The paper presents results of the studies on recycling of a group of composite materials with saturated reinforcement of various structures and chemical compositions. The environments including salt mixtures chosen for the considered composites reinforced with pressed fibre profiles satisfy the first and the most important quantity criterion. i.e. allow for achieving the required metal yield. For the composite of the highest yield level the quality of melted metal was analyzed which showed that the environment selected this way meets also another criterion that enables obtaining high quality alloys, thus allowing for their direct use in the process of reinforcing the composite casts. On the other hand, in the case of the composites reinforced with sinters the first criterion has not been met and, therefore, the metal quality in this case has not been assessed.