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Hybrid composite refers to as an attractive structural material due to its ability to provide a better combination of properties with respect to single-particle-containing composite. Composites wer...

In this work, mechanical milling of magnesium with SiC particles with variation of parameters, such as ball-to-powder ratio, milling speed, milling time, and process controlling agent (PCA), is reported. Milling was also conducted without using PCA to explore its role on the mechanical milling process. Milling was performed in a planetary ball mill. The results show that a uniform distribution of the reinforcement, good particle yield, and particle size reduction can be achieved by controlling the parameters. The milling powders were compacted using the underwater shock wave generated by the detonation of an explosive. The samples were characterized by XRD, scanning electron microscopy, and microhardness testing. Microstructural characterization revealed a well flown magnesium matrix enveloping reasonably well dispersed SiC particles. The results of microhardness testing reveal an increase in the hardness of the composite.

An improved multivoltine variety of Rajshahi silk fabric is used as material for investigation. This fabric is degummed to remove sericin, as sericin is soluble in hot water and highly responsible for the fading of dyed silk after washing. Rajshahi silk fabric is dyed with Reactive Brown 10 and Direct Orange 31 dyes. The color of the silk fabric becomes even and bright when it is dyed with 2.0% Reactive Brown 10 and 2.5% Direct Orange 31 after 50-60 minutes at 80-100°C. To achieve fast color, the silk fabric is treated with six modifying conditions prior to dyeing and among them, comparatively better modifying conditions are selected on the basis of color fastness upon exposure to sunlight in air and wash fastness in a soap solution. The modified Rajshahi silk fabric with 30% CH3COOH and 20% tannic acid together show better dyeing properties than modifications with other conditions and unmodified silk fabric. Direct Orange 31 shows better colorfastness than Reactive Brown 10 after exposure to sunlight in air and also after washing with a soap solution.

The shock consolidation of magnesium (Mg)/silicon carbide (SiC) composites using axisymmetric explosive fabrication setup is reported. Pure Mg and SiC powders are consolidated in a three-layered cylindrical assembly with the energy being derived from a high-detonation velocity explosive. The pressure of underwater shock wave is experimentally measured and simulated using AUTODYN 2D. Microstructural characterization of the samples revealed a well-flown Mg matrix enveloping near homogeneous SiC particles. Occasional clustering of SiC particles and interparticle melting is evidenced. Results of microhardness revealed that the presence of SiC particulates led to a substantial increase in the hardness of the composite. Fractography results indicate the lack of formation of ductile dimples, which is attributed to the presence of discontinuous SiC particles. The strengthening mechanism, the absence of reaction products, the structure–property correlation of the shock consolidated composite are discussed.