Good quality in composite castings can be confirmed primarily by their user. The producer is obliged to create
a good product that meets the user’s needs that should undergo quality control. Omission of technological
procedures and improper quality control may result in various defects like porosity. This paper presents the
characteristics of the casting defect, namely porosity, with a particular focus on porosity in suspension and
saturated metal composites. This defect is different, specific to composite castings, making its identification
very difficult. The aim of the study is to detect and describe porosity in composites with the use of microscopic
and submicroscopic examinations. The assessment of the porosity of the microstructure of composite castings
allowed for the formulation of the following conclusions: in addition to the porosity that occurs in castings of
classic materials (cast steel, cast iron, and non-ferrous metal alloys), metal composites also distinguish between
primary and secondary agglomerates, leaving the reinforcement space not filled, occluded bubbles, and separated
gas bubbles.
