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In the current studies an investigations were made to know the effect of 63 micron sized B4C particles addition on the mechanical and wear behavior of aerospace alloy Al2618 metal composites. Al2618 alloy with different weight percentages (2, 4, 6 and 8 wt. %) of 63 micron sized B4C particles reinforced composites were produced by stir cast process. These synthesized composites were tested for various mechanical properties like hardness, compression strength and tensile behavior along with density measurements. Further, microstructural characterization was carried by SEM/EDS and XRD analysis to know the micron sized particles distribution and phases. Wear behavior of Al2618 alloy with 2 to 8 wt. % of B4C composites were studied as per ASTM G99 standards with varying loads and sliding speeds. By adding 63 micron sized B4C particles hardness, compression and tensile strength of Al2618 alloy was enriched with slight decrease in elongation. Further, wear resistance of Al2618 alloy was enriched with the accumulation of B4C particles. As load and speed on the specimen increased, there was increase in wear of Al2618 alloy and its composites. Various tensile fracture surface morphology and worn surface behavior was observed by SEM analysis.

The demand for materials with an unusual combination of properties has increased tremendously at a level that cannot be attained through the use of conventional materials. This is especially true for materials used in aircraft, automotive and power generation applications. The microstructure and mechanical properties of Al7075 – 6, 9 and 12 wt.% WC-Co particles reinforced composites are shown in this study. Liquid metallurgy is used to create the composites. The planetary ball milling method is utilized to turn the WC-Co mixtures into cermets, and the particles with a size range of 30-40 µm are employed as reinforcement. SEM and EDS analyses were used to characterise the microstructure. ASTM standards are used to test the mechanical characteristics of both as cast Al7075 and Al7075-6, 9 and 12 wt.% WC-Co composites. SEM was used to perform fractography study on the prepared composite.

MMC based on aluminium (Al) were produced for light-weight applications especially in aviation and automobile areas. Present paper deals with the fabrication and mechanical performance of AA6061 matrix composites fortified with Al2O3 (alumina) and graphene particulates. Fluid metallurgy method namely stir casting route was employed for fabricating the hybrid composites. Al2O3p and graphene powder are mixed in different weight fractions in which graphene (1 wt. %) particle reinforcement is held consistent and Al2O3 reinforcement is differed freely with 5, 10 and 15 wt. %. Using optical analyser and SEM equipment, microstructural examination is carried out and the result reveals that the graphene and Al2O3 particles prevalently are homogeneously appropriated on the grain limits of Al matrix and Al2O3 particles are disseminated between graphene in the as-cast AA6061 MMC’s. Detailed analysis on investigation of the microstructure and mechanical aspects of Al6061-graphene-Al2O3p composites is presented by following ASTM guidelines, results uncovered that with increment in reinforcement particles, there is an enhancement in the hardness, ultimate strength, yield strength and a decline in the elongation values was however noticed when contrasted with Al6061 alloy. Fractography investigation revealed dimples in unreinforced alloy and the composite.

In the present investigation synthesis, microstructure, mechanical and wear behavior of 5 weight percentage of nano Al2O3 particulate reinforced AA7475 alloy composites has been reported. AA7475 matrix composite containing nano Al2O3 were fabricated by conventional stir casting method. The microstructures of the composites were examined by scanning electron microscopy. Further, mechanical and wear behavior of as cast AA7475 alloy and AA7475 - 5 wt. % nano Al2O3 composites were studied. Mechanical properties like hardness, ultimate, yield strength and percentage elongation were evaluated as per ASTM standards. Pin on disc apparatus was used to conduct the dry sliding wear tests. The experiments were conducted by varying loads and constant sliding speed of 300rpm for sliding distance of 4000m. Microstructural observation revealed the uniform distribution of particles in the AA7475 alloy matrix. From the analysis, it was found that the hardness, ultimate tensile strength and yield strength of composites were increased due to addition of nano Al2O3 particle in the AA7475 alloy matrix. Percentage elongation of the composite decreased in 5 wt. % nano Al2O3 reinforced composites. Further, the volumetric wear loss was found to increase with the load and sliding distance for all materials. Worn surface analysis made by using scanning electron micrographs to know the various mechanisms involved in the wear process.

Nano particulates fortified metal lattice composites are finding extensive variety of utilizations in car and sports hardware fabricating businesses. In the present investigation, an endeavor has been made to create copper-zinc-nano ZrO2 particulates strengthened composites by utilizing fluid liquefy technique. 4, 8 and 12 wt. % of nano ZrO2 particulates were added to the Cu-Zn base grid. Microstructural studies were finished by utilizing SEM and EDS examination. Mechanical behavior of Cu-Zn-4, 8, 12 wt. % of nano ZrO2 composites were assessed according to ASTM benchmarks. Checking electron micrographs uncovered the uniform dispersion of nano ZrO2 particulates in the copper zinc composite network. EDS examination affirmed the nearness of Zr and O components in nano ZrO2 strengthened composites. Further, it was noticed that hardness, UTS, yield quality of Cu-Zn composite expanded with the expansion of 4, 8 and 12 wt. % of nano ZrO2 particulates. Ductility of nano composites was decreased by adding zirconium oxide particulates. Fractography of tensile specimens were carried out by using SEM micrographs to understand the failure mechanisms. &nbsp

The paper reports a study on wear properties of boron carbide reinforced Al metal matrix composite processed via stir casting route at lower temperature of 775 o C using halide salt K 2 TiF 6 with ratio 0.05Ti/B 4 C p to enhance better wettability. Fairly uniform distribution of B 4 C p in the matrix with no segregation is seen and revealed from SEM microphotographs. Micro hardness of the alloy and the composite was determined using Vickers micro hardness tester and found to increase with increase in volume fraction of B 4 C p addition to as cast 6061Al alloy. Pin-On-Disc tribometer was used to analyze wear behaviour of prepared composite and the alloy by applying normal load of 49.05m/s for a sliding velocity ranging from 3.34m/s - 10m/s up to a sliding distance of 565.4m at room temperature. Minimum wear rate was observed for 6061Al+ 6% B 4 C p at sliding velocity of 6.67m/s, normal load of 49.05N with sliding distance of 565.4N compared to 6061Al+ 4% B 4 C p composite and as cast 6061Al alloy. Worn surface were studied using optical microscopy to understand the wear mechanism exhibited by composites prepared.

A systematic study has been conducted to investigate the matrix properties by introducing nanosize ZrO2 (60-100 nm, 0.5–10 wt.%) fillers into an epoxy resin. High shear mixing process was employed to disperse the particles into the resin. The experimental results indicated that the frictional coefficient and wear rate of epoxy can be reduced at rather low concentration of nano-ZrO 2 . The lowest specific wear rate 0.1 x 10 -4 mm 3 /Nm is observed for the composites with 0.5 wt.% which is decreased by 95% as compared to the value of unfilled epoxy. Although the incorporation of nano-ZrO 2 particles leads to increased flexural modulus and flexural strength of epoxy, the wear performance of the composites does not correlate with these static mechanical properties. In contrast, there is a positive correlation between wear resistance and impact strength (i.e. increase in impact strength correlates with a decrease in specific wear rate).