Measurement of Non-Metallic Inclusions in the Size Range of 10-20 mu m by LiMCA

Regular monitoring of the melt quality is employed in Aluminum cast houses production where optimized processes and high quality are required. A well established method for the quantitative measurement of non-metallic inclusions is the LiMCA system. In this method, inclusions flowing together with the liquid Aluminium through a 300 mu m orifice of a submerged glass tube are detected due to their high electrical resistance. The LiMCA system can identify the size, typically in the range between 20 m and 300 mu m and number of particles in the liquid Aluminium. Increasing product quality standards have resulted in demands to monitor particles even smaller than 20 mu m. This paper reports results of a parametric study to assess the capability of of the LiMCA system to monitor non-metallic inclusions in the particle size range of 10-20 mu m through changing the orifice hole size and by adjustment of the basic measurement parameters.