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The effects of vacuum induction melting and various concentrations (range of 0–8% by weight) of the titanium aluminium carbide (Ti2AlC) phase on the mechanical and tribological properties of Aluminium hypereutectic alloy (A390) were investigated. The addition of Ti2AlC particles enhances the strength and wear resistance of A390 alloy and also exerts a positive effect on its ductility, Moreover aerospace and automotive brake rotors deserved high strength and high wear resistance. The quick induction heating process could decrease the thermal energy degradation of the Ti2AlC particles into an Al alloy matrix alloy. The structural, microscopic and elemental analysis carried out to observe the hard precipitate components and reveal the various phases of the composites. The addition of Ti2AlC inclusions altered the morphology of eutectic silica to be globular and improved the grain size and evenly distributed within the A390 (Al-16Si) matrix. As the content of Ti2AlC reaches 8 wt% the strength and microhardness of the composites increased 74% and elongation decreased 2.1% (UTS = 285 MPa, H = 127VMH and EI = 1.1%). The tensile and fracture behaviour of the composites has been studied at 30 °C, 150 °C, and 250 °C. The Johnson-Cook model theoretically calculated the accurate flow stress of the Al-16Si/Ti2AlC composites. The negligible decrease in strength and ductility at 250 °C was observed. The root mean squared error (RMSE) and mean absolute percentage error (MAPE) values for the stress-strain curves prove the higher relationship between the theoretical and experimental values. The composites containing 8 wt% Ti2AlC reinforcement significantly enhanced the mechanical behaviour with a porosity < 2.23%.Therefore this composite exhibited appreciable tribological properties. It appeared that the wear mechanism of the composites abrasive wear at applied pressure 0.2 MPa with sliding distance 2000 m was prevailing. The ANN model addressing the parameters which influence the wear rate and friction coefficient as well as the experimental wear analysis of these composites was correlated precisely with the results of this model. [ABSTRACT FROM AUTHOR]

Direct water spraying (DWS) is an approach similar to ablation casting using direct impingement of water spray on the solidifying casting but is modified in that it no longer relies on eroding removal of the sand bound by water-soluble binders. A removable part of the sand mold is withdrawn during the process, and water is directly sprayed on the exposed casting surface. Two commercial casting Al alloys, i.e., A413 with short to zero and A356 with a wider freezing range, were processed by the DWS method. Comparison of the conventional and DWS-processed castings with respect to the microstructure and mechanical properties was evaluated via computer-aided thermal analysis, metallography, and tensile testing. The average ultimate tensile strength (UTS) increased from 126 to 193 MPa in A356 and 139–159 MPa in A413 by applying the DWS method. The elongation was increased from 2.8 to 11% in the DWS A356 and from 1.8 to 5% in the DWS A413. The secondary dendrite arm spacing (SDAS) was decreased from 80 µm in A356 to 44 µm and from 68 µm in A413 to 32 µm in the respective DWS-processed counterparts. The experimental results confirmed that a longer freezing range is more favorable with the DWS process, producing improved castings with higher tensile properties. [ABSTRACT FROM AUTHOR]

Elements that are deliberately added to aluminum alloys or are incorporated into the alloy later depending on the production process affect the final product properties. In addition, liquid metal cleaning is important in minimizing undesirable elements. Considering the production process, one of the most harmful impurities that is likely to pass into the alloy via diffusion for aluminum is the element, Fe. It is known that this is due to the fact that although Fe is highly soluble in liquid aluminum and its alloys, it has very little solubility in solids. Depending on the Fe content, mechanical properties, porosity and fluidity properties are affected in aluminum alloys. In this study, stainless and carbon steel rods were dipped into the melt at 700 °C and 750 °C for 1, 2 and 5 h. Castings were performed before and after degassing. Four-channel fluidity mold with different section thickness was used in the trials. Additionally, microstructure characterization was performed under varying casting conditions. Fluidity Index was proposed which is a single value measured from all fluidity values in different sections. When the results were examined, it was determined that the diffusion material, holding time, casting temperature and liquid metal cleanliness had an effect on the fluidity. Due to the increase in diffusion time, a decrease in fluidity was observed in both carbon steel and stainless steel. It was found that fluidity was significantly reduced when using stainless steel. [ABSTRACT FROM AUTHOR]