Since 1995, the University of Alabama - Birmingham has been conducting a multi-phase research project to address the problem of macro-inclusions in steel castings. Macroinclusions can significantly degrade the machining of parts -- even to the point of breaking tools. This is costly on high-speed machining lines and reduces plant productivity. Macroinclusions serve as initiation sites for failures in the casting. Macroinclusion removal and weld repair typically adds 25% to the cost of casting production.
The first phase of the research was to identify the significant causes of macroinclusions in steel castings and devising methods to minimize or eliminate their occurrence. Participating foundries saw measurable improvements in reducing dirt and the number of welds requiring repair. In one foundry, for example, the number of welds requiring repair dropped from an average of 21.1 per casting to 3.7 per casting -- an 82% improvement.