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Over the last few decades, particle-reinforced Zn based metal matrix composites have begun to supplant monolithic Zn matrix. High strength to weight ratio, near-isotropic characteristics and cost are the key factors. The objective is to analyze the mechanical and wear activities of a unique composite Zn-Sn alloyed with nano B4C based on the literature. The effect of nano-sized B4C particulates on Zn85-Tin 15alloy is investigated. Nano B4C particulates are employed as reinforcement. Instep of B4C 0%, 2%, 4%, 6% and 8% by weight, composites are manufactured utilizing a two-step approach method. On a pin-on-disc type wear testing machine, wear tests were performed on all specimens under various operational settings such as typical loads of 10N, 20N, 30N and 40N and sliding speeds of 1.4, 1.8, 2.3 and 2.8 m/s at 2000m sliding distance and 90mm track diameter. Each specimen was subjected to 16 wear tests, resulting in a total of 80 wear tests. As the usual load increases, the volumetric wear rate increases, the volumetric wear rate reduces as the sliding speed increases. Corresponding worn out surface, wear debris and EDS are revealed. The surface roughness and surface hardness values increase as the sliding speed increases. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

MMCs exhibit increased modulus, strength, and fatigue strength. In MMCs, reinforcements can either be discontinuous or continuous or a combination of both. Owing to lower aspect ratio, and random orientation of the reinforcements, discontinuously reinforced composites exhibit comparatively higher isotropic properties than composites that are continuously reinforced. In the current research an attempt has been made to carry out experiments on Al-7Si and Fly ash and Graphite hybrid composites which were fabricated in steps of 3 wt.% of Flyash with 3 wt.% of Graphite and 3 wt.% of Flyash with 5 wt.% of Graphite for 25mm and 75mm diameter dies. Microstructural characterization of the specimens prepared following SEM, XRD, and EDS. Mechanical properties like hardness, yield strength, and ultimate tensile strength were evaluated as per ASTM standards. The composites prepared in 25 mm cast iron die were exhibited superior mechanical properties as compared to the composites prepared in the 75 mm diameter cast iron die. Further, with the addition of fly ash and graphite particles mechanical properties of Al-7Si alloy were improved [ABSTRACT FROM AUTHOR]

In the current studies an investigations were made to know the effect of 20 to 25 micron sized B4C particles addition on the physical and mechanical behaviour of Al7010 alloy metal composites. Al7010 alloy with 4 and 8 wt.% of B4C composites were produced by stir cast process. These synthesized composites were tested for numerous mechanical properties like hardness and tensile behaviour along with density measurements. Further, microstructural characterization was carried by SEM and XRD analysis to know the micron sized particles distribution and phases. By adding 20 to 25 micron sized B4C particles hardness and tensile strength of Al7010 alloy was enriched with slight decrease in elongation. Further, density of Al7010 alloy was decreased with the accumulation of B4C particles. Various tensile fracture behaviours were observed by SEM analysis. [ABSTRACT FROM AUTHOR]

The paper focused on an experimental study on the microstructural, mechanical, and wear characteristics of 15 wt.% alumina (Al2O3) particulates with an average particle size of 20 µm, reinforced in Al2014 alloy matrix composite as-cast and heat-treated samples. The metal matrix composite (MMC)samples were produced via a novel two-stage stir-casting technique. The fabricated composite samples were subjected to evaluate hardness, tensile strength, fatigue behavior and wear properties for both as cast and T6 heat-treated test samples. The Al2014 alloy and Al2014-15 wt.% Al2O3 MMCs were in solution for 1 h at a temperature of 525 °C, quenched instantly in cold water, and then artificially aged for 10 h at a temperature of 175 °C. SEM and X-ray diffraction analyses were used to investigate the microstructure and dispersion of the reinforced Al2O3 particles in the composite and the base alloy Al2014. The obtained results indicated that the hardness, tensile and fatigue strength and wear resistance increased when an amount of Al2O3 particles was added, compared to the as-cast Al2014 alloy and it was observed that after subjecting the same composite samples to heat treatment, there was further enhancement in the mechanical and wear properties in the Al2014 matrix alloy and Al2014-15 wt.% Al2O3 composite samples. [ABSTRACT FROM AUTHOR]

The current work intended to synthesize Al-Mg-Si (Al6061)-B4C particulate metal matrix composites by varying weight percentage of B4C particulates (0, 3 and 6 wt.%) with an average particle size of 80 to 90 microns by vortex process (melt technique). The incorporated B4C particles distribution in the Al6061 alloy matrix was studied by SEM micrographs and confirmed the thorough distribution of carbide particles in the matrix. EDS spectrums and XRD patterns were obtained for Al6061 and its composites to identify various elements and phases present in the Al6061-B4C composites. Al6061 alloy with 3 and 6 wt.% of B4C composites was subjected to hardness, tensile, impact and fatigue behavior evaluation. By adding boron carbide particles hardness, tensile and impact strength of Al6061 alloy was improved with slight decrease in fatigue strength. Further, various fracture morphologies were studied on tensile, impact and fatigue fractured surfaces using SEM micrographs. [ABSTRACT FROM AUTHOR]

In this paper, an impact of Al2O3 and B4C particles addition on the mechanical properties of Al6061 alloy has been studied. Al6061 alloys with 5% wt. of Al2O3 and 9% wt. of B4C particles reinforced composites were fabricated by vortex method with novel two sate reinforcement addition procedures. Al6061-Al2O3-B4C hybrid composites were subjected to microstructural characterization using SEM, EDS and XRD patterns. SEMs of Al6061 alloy with 5% wt. Al2O3-9%wt. B4C hybrid composites revealed thorough circulation of particles in the Al matrix, EDS and XRD patterns confirms the various elements and phases in hybrid composites. Further, these composites were evaluated for hardness, tensile and impact behaviour as per ASTM standards. Dual particles reinforced hybrid composites were exhibited superior hardness, tensile and impact properties with reduction in ductility. Fractography analysis was carried out on tensile and impact fractured specimens using SEM to know the impact of dual particles on the fracture behaviour of Al6061 alloy. The developed composites are superior in strength to weight ratio hence can be utilized for automotive applications to replace conventional materials. [ABSTRACT FROM AUTHOR]

In the current investigation, efforts are being made to produce an Al2014-Al2O3p composite with an average particle size of 88 μm by liquid stir casting route. 9, 12 and 15 weight proportions of Al2O3p were added to the Al2014 base alloy. By using SEM and EDS testing, microstructural studies have been conducted. Al2014-9, 12 and 15 weight proportion of Al2O3p composites mechanical behavior is determined in line with ASTM standards. Electron microscopic images showed that alumina (Al2O3p) particles are dispersed uniformly within the Al2014 composite matrix. EDS study confirmed the proximity of Al and O elements to composites reinforced by Al2O3p. It is also found that Al2014-Al2O3p composite hardness, UTS, and yield strength are improved by the addition of 9, 12 and 15 weight proportion of Al2O3p. Due to the addition of alumina particles in the Al2014 matrix alloy, the ductility of the produced composites decreases. Tensile fractography is performed using SEM to consider the mechanisms for failure. [ABSTRACT FROM AUTHOR]

In the current investigations, the microstructure, mechanical properties and tensile fractography of Al2219 alloy with 2 and 4 wt.% of 90-micron-sized titanium carbide (TiC) particles reinforced composites were developed. The composites containing 2 and 4 wt.% of TiC particles in the Al2219 alloy were created by melt stir technique. During the preparation of composites, TiC particles were preheated to a temperature of 400 °C, and these preheated particles were dispersed into the Al2219 alloy matrix in two steps to improve the wettability between Al matrix TiC particles. Microstructural examinations on the specimens were carried out by SEM, EDS and XRD. Mechanical properties of 2 to 4 wt.% of micro-TiC particles reinforced Al alloy composites were evaluated as per ASTM standards. Microstructural studies by SEM and EDS confirmed the dissemination and the presence of micro-TiC particles in the Al2219 alloy matrix. The presence of TiC phase in Al matrix was confirmed by the XRD patterns. The hardness, ultimate yield and compression strength of Al2219 alloy enhanced with the incorporation of 2 and 4 wt.% of micro-TiC particles. Further, ductility of Al2219 alloy decreased with the presence of TiC particles. The prepared Al2219 alloy with TiC particles composites was studied for tensile failure analysis using SEM microphotographs to reveal the several mechanisms involved in the tensile fracture. [ABSTRACT FROM AUTHOR]

In the present research, an effect of nanographite and zirconium oxide (ZrO2) dual reinforcement addition on the mechanical and wear behaviour of Al7075 alloy has been studied. The Al7075 alloy with constant 3 wt.% of graphite particles and varying (3 and 6) weight percentages of ZrO2 particle-reinforced hybrid composites were fabricated by stir casting method. The synthesized dual particle-reinforced Al7075 alloy hybrid composites were subjected to microstructural studies, mechanical and wear properties testing. Microstructural characterizations of obtained samples were carried out by scanning electron microscopy. The graphite and ZrO2 particles were evenly distributed in the Al7075 alloy matrix. The hardness, impact and tensile strength of hybrid composites have been increased with the addition of dual reinforcements. There was slight decrease in the ductility of the Al7075 alloy after the incorporation of these reinforcements. The wear behaviour of the prepared samples was tested at varying loads and speeds. The hybrid composites exhibited a superior wear resistance as compared to base matrix alloy Al7075. Various fracture and wear mechanisms were observed in the Al7075 alloy with graphite and ZrO2 particle-reinforced composites using SEM. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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The present work aims at producing 6061Al metal matrix composites reinforced with 5 and 7wt% of B4C particulates at temperature of 750°C via melt stirring method involving two-step additions. In order to improve wettability and to avoid agglomeration of B4C particulates, K2TiF6halide salt in the ratio of 0.2 were mixed with B4C particulates and the mixture were being dropped into the melt batch wise (twice). The prepared composites were characterized by scanning electron microscopy (SEM)/energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD) studies. SEM microphotographs revealed homogeneous dispersion of B4C particulates without agglomeration in 6061Al matrix. Indexing of the XRD peaks confirmed the presence ofα-Al, B4C and minor phases like Al3Ti and Al3BC. Presence of Al3Ti phase as confirmed by XRD and EDX studies is clear indication of Ti compound/layer formed around the B4C particles. Further, improvements in mechanical properties like hardness, tensile and compression strengths of the 6061Al matrix were obtained in the composites. [ABSTRACT FROM PUBLISHER]

Abstract: In the present work, binary Al–3Ti and Al–3B master alloys were prepared at different reaction temperatures in an induction furnace by the reaction of halide salts like potassium fluoborate and potassium titanium fluoride with liquid molten Al. The reaction temperatures of 800, 900 and 1000°C were selected while the reaction time was kept constant at 60min for the preparation of master alloys. These master alloys were characterized by chemical analysis, particle size analysis, XRD and SEM/EDX studies. The indigenously developed master alloys were used for grain refinement studies of Al–7Si alloy and evaluated for their grain refining ability by CA-CCA studies. The present results suggest that, the reaction temperature influences the size, size distribution and morphology of the intermetallic (Al3Ti in Al–3Ti and AlB2/AlB12 in Al–3B) particles present in Al–3Ti and Al–3B master alloys. Grain refinement studies of Al–7Si alloy reveal that, Al–3Ti and Al–3B master alloys prepared at 800°C–60min have shown better grain refining efficiency on Al–7Si alloy when compared to the master alloys prepared at 900°C–60min and 1000°C–60min, respectively. In addition, B-rich Al–3B master alloy shows efficient grain refinement than Ti rich Al–3Ti master alloy. [Copyright &y& Elsevier]