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The development of lightweight and high-strength materials is critical for many industries, including aerospace, automotive, and electronics. Metal matrix composites (MMCs) have shown great promise in meeting these requirements. The structural and physical properties of Al6061 alloy reinforced with hybrid MMCs, including TiB2, SiC, and fly ash (FA), were investigated in this research review. The MMCs investigated were made using the stir-casting process. Their microstructure, structural characteristics, and mechanical features were examined. The inclusion of TiB₂ and SiC enhanced the composite’s hardness, tensile strength, and wear resistance, while the addition of FA lowered its density and improved its thermal and corrosion resistance. However, the volume percentage, particle dimension, and arrangement of the reinforcing components all had an effect on the physical characteristics of the composite. Therefore, the optimum combination of the reinforcing materials must be carefully selected to achieve the desired properties. The result of this review provides valuable insights into the development of high-performance MMCs for various industrial applications.

High performance composite reinforced with unidirectional continuous fibers are used in applications requiring high stiffness, high strength and light weight. Because of the high stiffness of the reinforced continuous fiber, the longitudinal performance of such unidirectional composites is greatly enhanced, but their transverse performance is so weak. The nature of the fiber/matrix interface is one of the important factors which determine the unique properties of the fiber reinforced metal matrix composites (MMCs). So, the current study is focused on the fracture behavior of the interface. Both stress state of the interface and crack parameters of the perpendicular crack to the interface for unidirectional fiber reinforced metal matrix composites under the transverse loading are investigated by using elastic-plastic finite element analysis. Different fiber volume fractions (5~60%) and arrangement (square and hexagon) of fibers were studied numerically. The fiber/matrix interface was treated as multi thin layer with different material properties. The fiber is assumed as linear elastic SiC and the matrix is assumed as elastic-plastic Ti-15-3 Titanium alloy. The results show that the stress distributions of the multi thin layer model have much less changes compared with a single interface case. And the properties of the interfacial zone affect the stress distribution, crack behavior and mechanical behavior of the fiber reinforced metal matrix composite.

An analytical model based on Eshelby equivalent inclusion approach and Mori-Tanaka mean field extension was established by introducing numerical matrix and composite secant/tangent moduli to simulate the stress-strain curve of particulate reinforced composite. The same modeling work was also carried out by FEM analysis based on the unit cell model using a commercial ANSYS code. The modeling results by both models on evolution of the load carried by the SiC particles during straining provide strong evidences to back up the strengthening mechanism of the load sharing. The modeling was also carried out to study the influence of different volume fractions and aspect ratios on elastic modulus and yield strength of the composites with different reinforcing particles to get a better understanding of strengthening mechanisms of the materials. A concept of microstructure design for particulate reinforced materials was argued based on new developments in understanding of the relationship between properties and microstructure. The optimal geometry of particulate reinforcement was discussed in respect to the best match up with matrix mechanical behavior.

In this study, a novel AA7075-TiO₂ metal matrix composite was machined utilizing a biosilica mixed EDM technique and the surface roughness and material removal rate are optimized. The biosilica particles are produced from waste maize cobs and then silane-treated. The optimization of process variables wasperformed using Taguchi grey relational approach with a process variable of peak current, gap voltage and pulse-on time. Results revealed that the gap voltage is the most important process variable, since it has a larger max-min difference of 0.25. In order to create a high MRR of 11.6mm³/min and a surface roughness of 2.25 m, the maximum GRG of 0.79 for Trial 1 (A2B1C3) represents the most ideal process variable group. The best results appear to be obtained with a peak current of 10 A, a gap voltage of 20V, and a pulse-on time of 140$\mu$s. The new GRG, however, is around 2.51% better than the anticipated optimized process variables of A2B1C3 with an old GRG of 0.79, according to the confirmation research. The new MRR of 11.89mm³/min and the surface roughness of 2.30s with a GRG of 0.81 are based on the optimized new process variables (A1B1C3).

High cost, low response frequency and dynamic time delay are general problems in most of the existing micro magnetic compass (MMC). According to the characteristic of mini-UAV navigation and control system, this paper presents a silicon MEMS-based integrated MMC, determining attitude by both accelerometers and anisotropic magneto resistance (AMR) sensors through estimating the mini-UAV state utilizing the Z-direction gyroscope. On the other hand, the magnetic disturbance around the MMC is calibrated. The experiments show that this MMC, with good collective performance, 0.5° heading accuracy, 1/5 cost and 50Hz response frequency, is able to meet the requirements of extraordinary precision, low cost and real time communication.

Magnesium AZ91D alloys reinforced with fine SiC particles (AZ91/SiCp) were fabricated by mechanical milling, hot pressing and extrusion. The properties of AZ91D alloy composites were generally improved by SiC addition. The Young's modulus and hardness increased correspondingly with SiC addition up to 20-volume percent. However, the UTS and proof stress showed a maximum value at 15-volume percent and decrease at 20-volume percent. Nevertheless, the UTS values of the 20-volume percent SiC composites increased when the milling duration was increased. The influence of the volume fraction of SiC particle and milling term on mechanical properties, microstructure and density will be discussed.