Influence of centrifugal casting parameters on Al-Mg alloy castings microstructure and mechanical properties

The paper is dedicated to the process of obtaining hollow castings on a horizontal centrifugal casting machine. The influence of mold rotation speed and the melt pouring process mechanical properties of as-cast parts made of AlMg5, alloyed by small amount of transition and rare earth metals, is represented. Mold pouring processes and crystallization kinetics depend on mold rotational speeds 1100, 1500 and 2000 rpm were studied by using numerical modeling. The influence of the specified mold rotation speeds on the structure and mechanical properties of castings is shown. It is also determined that the installation of a foam ceramic filter in the pouring cup of a centrifugal casting machine ensures melt laminar flow when pouring it into a mold. It was determined that 1500 rpm is the most favorable rotating speed from the points of optimal hydrodynamic mold filling processes and casting crystallization kinetics. It was also shown that with the increase of a mold rotation speed from 1100 to 2000 rpm, the thickness of the defective inner layer decreases, the alloy structure refines, and the mechanical properties of as-cast detail increase the next way: at 1500 rpm (sigma 0.2-by 10%, sigma B - by 25%, delta - 3 times), at 2000 rpm (sigma 0.2-by 18%, sigma B - by 31%, delta - 4 times), compared to products obtained by steel mold gravity casting. Centrifugal casting technology ensures the mechanical properties of cast blanks even higher than those of deformed AlMg5 alloys, the values of which approach those of AlMg6 alloy products.