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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]

The 6016 aluminum alloy has good plasticity but low strength. In this work, Al-Ti-Sc master alloy was prepared by thermite reduction method in order to obtain an effective grain refiner with a simplified preparation process and a reduced cost. The refining effects of the ternary master alloy on the 6016 aluminum alloy were checked to improve the strength and plasticity simultaneously. The chemical reactions during the preparation process of the Al-Ti-Sc master alloy was studied by thermodynamic software of HSC 6.0. The content of Sc and Ti in the master alloy reaches 2.48 wt% and 1.4 wt%, respectively, on proper experimental conditions, and the main phases of the master alloys are α-Al and Al 3 (Sc,Ti) phase. In the refined alloys, the average grain size can reach 27 μm, and the ultimate tensile strength and the elongation after fracture reaches 280 MPa and 35% in cast state, respectively. Compared to the pristine 6016 aluminium alloy, the significantly enhanced strength and good plasticity of the refined alloys contribute to the combined effects of grain refinement and precipitated phase strengthening. For the fracture of low doped alloys, originates from cleavage fracture mechanisms, and for the ones with high dosages, ductile fracture becomes dominant. [Display omitted] • A series of ternary Al-Ti-Sc master alloys were prepared by thermite reduction of Sc 2 O 3 and TiO 2. • The effects of technical factors on Sc and Ti contents were researched during the thermite reduction process. • The main second phase in Al-Ti-Sc master alloys is a well-matched Al 3 (Sc,Ti) solid-solution phase. • Both strength and plasticity of 6016-based alloys are improved significantly by addition of Al-Ti-Sc master alloys. • The strengthening mechanisms of the refined 6016-based alloys by Al-Ti-Sc master alloys were clarified. [ABSTRACT FROM AUTHOR]

• The joint quality of perforated CFRP and aluminum alloy stick-self-punch riveting was studied. • The static characteristics and the failure modes of the joint were analyzed. • Results showed that the main failure mode of HH-BR joint was laminate tearing. • The reasons why HH-BR joints have better performance than H-BR and SPR joints were explained. This paper explores the new hybrid hole-drilled bonding and self-piercing riveting (HH-BR) connection technique to enhance the strength and overall performance of carbon fiber reinforced polymer (CFRP) and dissimilar metal materials at joint interfaces. The forming quality, mechanical performance, failure modes, and fracture characteristics of the CFRP and aluminum alloy joints utilizing the HH-BR procedure were analyzed in detail and compared with the joints of the hole-less adhesive-bonding self-piercing riveting (H-BR) and self-piercing riveting (SPR). At the same time, the effects of different rivet performance levels, overlap lengths, and various fiber orientation angles on joint performance were discussed. The results show that joints made by the HH-BR technique have a substantial advantage in terms of achieving superior mechanical performance and interlocking value. Firstly, HH-BR joints with bent rivets and torn fibers have connection strengths that are noticeably higher than those with CFRP laminate delamination or rivet pullout failure. The use of the HH-BR technique for joining CFRP/aluminum alloy culminated in reduced strength loss and higher energy absorption than H-BR and SPR joints, improving the joint's overall strength. Secondly, the interlock value between the rivet and the plate, is what essentially determines the strength of HH-BR joints, especially evident in connections with 0°/90° fiber orientation and more overlap lengths. The results also show that there is a strong relationship between the height of the rivet head and the joint's mode of failure, and the height of the rivet head is affected by the rivet force. Furthermore, the interlock value's magnitude, the joint's remaining bottom thickness, and the metal material's capacity for plastic deformation are all directly correlated. [ABSTRACT FROM AUTHOR]