Showing papers on "Metal matrix composite published in 2019"

Experimental study and analysis of machinability characteristics of metal matrix composites during drilling

Abstract: In this study, the metal matrix composite materials were produced by hot press with various production parameters. The drilling experiments were performed on computer numerical control vertical machining centre without cutting fluid. Analysis of variance (ANOVA) was carried out in order to determine the effects of the production parameters on thrust force and surface roughness of metal matrix composites drilled with different feed rate. The effect of production parameters such as temperature, pressure and reinforcement ratio were investigated, and their effects were presented. The optimal level for each production parameters was determined by ‘Maximize the S/N ratio approach with a Taguchi design’. The test results revealed that the reinforcement ratio was the main factor affecting the surface roughness of the metal matrix composites for both feed rate. However, same singularity was not matter on thrust force due to close contribution rates of production parameters and high error rates of analysis. In literature, an increase on the thrust force and the surface roughness values was reported as the feed rate increased during machining. Nevertheless, in our MMCs system, the thrust force and the surface roughness values were in tendency of declination as the feed rate increased which makes this study more novel research.

Microstructural, mechanical and corrosion behaviour of Al─Si alloy reinforced with SiC metal matrix composite

Abstract: The aim of the present study is to investigate the effect of Si and SiC addition on the microstructure, mechanical, and corrosion properties of Al matrix-based composites. Al–Si (2 wt% fixed) alloy...

Microstructure and mechanical properties of friction stir welded AA6092/SiC metal matrix composite

Abstract: There is a need for improved understanding on the effects of friction stir welding (FSW) on the metallurgical and mechanical properties of aluminium matrix composite (AMC). In this study, AA6092/SiC/17.5p-T6 AMC joints were produced by using FSW with varying tool rotation and traverse speeds. The microstructural characterisation by scanning electron microscopy equipped with electron backscattered diffraction (EBSD) system revealed a substantial grain refinement and a homogeneous distribution of reinforcement particles in the nugget zone. The grain size of the nugget zone was greatly influenced by weld pitch, as a key indicator to control the amount of heat input, exposure time and cooling rate. Vickers microhardness profile across the welding zone revealed a significant difference in microhardness among the base metal, heat affected zone, thermo-mechanically affected zone and nugget zone. The tensile strength of the cross-weld specimens showed a high joint efficiency of about 75% of the base metal combined with relatively high ductility. Low-cycle fatigue properties were investigated in the axial total strain-amplitude control mode (from 0.3% to 0.5%) with R = e min / e max = − 1 . The results indicate that the fatigue life of the cross-welded joints varies with grain size in the nugget zone and it is lower than that of the base metal. A significant improvement of fatigue life is found to be related to the finer equiaxed grains dominated by high angle grain boundaries in the nugget zone.

Microstructure, wear and corrosion characteristics of Cu matrix reinforced SiC–graphite hybrid composites:

Abstract: The aim of the present study is to investigate the effect of SiC-graphite reinforcement on the properties of pure copper. Copper matrix composites with SiC-graphite reinforcement (0, 2.5,5, 7.5 and...

An Overview of the Recent Developments in Metal Matrix Nanocomposites Reinforced by Graphene.

Abstract: Two-dimensional graphene plateletes with unique mechanical, electrical and thermo-physical properties could attract more attention for their employed as reinforcements in the production of new metal matrix nanocomposites (MMNCs), due to superior characteristics, such as being lightweight, high strength and high performance. Over the last years, due to the rapid advances of nanotechnology, increasing demand for the development of advanced MMNCs for various applications, such as structural engineering and functional device applications, has been generated. The purpose of this work is to review recent research into the development in the powder-based production, property characterization and application of magnesium, aluminum, copper, nickel, titanium and iron matrix nanocomposites reinforced with graphene. These include a comparison between the properties of graphene and another well-known carbonaceous reinforcement (carbon nanotube), following by powder-based processing strategies of MMNCs above, their mechanical and tribological properties and their electrical and thermal conductivities. The effects of graphene distribution in the metal matrices and the types of interfacial bonding are also discussed. Fundamentals and the structure–property relationship of such novel nanocomposites have also been discussed and reported.

Microstructure and Mechanical Properties of TiC-Reinforced 316L Stainless Steel Composites Fabricated Using Selective Laser Melting

Abstract: TiC/316L stainless steel (316Lss) metal matrix composite parts have been formed using selective laser melting (SLM). In this study, we have investigated the influence of the TiC mass fraction on the microstructure evolution, microhardness, friction properties, wear properties, and corrosion resistance of the TiC/316Lss composites. The results show that the microhardness increased by the addition of the TiC mass fraction. In terms of friction and wear properties, the corrosion resistance initially increased, and then decreased. Compared with the pure 316Lss (298.3 HV0.2), the microhardness of the TiC/316Lss composites, which were formed with 2 wt% TiC, was raised to 335.2 HV0.2, which was a 12.4% increase, while the average friction coefficient was 0.123. The reason for this is that the addition of TiC can effectively refine the cell size, and as the TiC content increases, the refinement effect is more obvious. During the melting process, TiC particles act as nucleation centres, hindering the growth of crystal cells, promoting the formation of the austenite phase, and forming fine equiaxed structures, which increases the strength. However, excessive TiC particles aggravate the spheroidisation during the process of SLM, leading to increased defects, as well as a decrease in density and corrosion resistance.

The porosity, microstructure, and hardness of Al-Mg composites reinforced with micro particle SiC/Al2O3 produced using powder metallurgy

Abstract: In this study, Al-Mg metal matrix composite (MMC) materials reinforced with micro-sized SiC, Al2O3 particles were manufactured using powder metallurgy. SiC and Al2O3 particles with 1 μm size were added to the Al-Mg matrix at different volume ratios (15–30%). A mixture of Al, Mg, reinforcement (SiC, Al2O3) powders was mixed at a speed of 16 rpm over a 24 h-time period for a homogeneous dispersion. The mixed powders were pressed at 300 and 600 MPa. Composite materials produced at different pressures were sintered under for 30, 60, 90 min and at 300, 400, 500 °C and allowed to cool in the furnace. The microhardness, porosity, microstructure of Al-Mg/SiC and Al-Mg/Al2O3 composites were investigated and characterized. The highest porosity ratio for all test conditions was measured as being 17% in the Al-Mg composite reinforced with 15% SiC produced at 300 MPa and 400 °C for 90 min. The lowest porosity ratio was measured as being 5.4% in the Al-Mg composite reinforced with 15% SiC produced at 600 MPa and 500 °C for 90 min. In their microstructure studies, a generally homogeneous microstructure was observed.

Experimental investigations on wear and friction behaviour of SiC@r-GO reinforced Mg matrix composites produced through solvent-based powder metallurgy

Abstract: In the present study, wear and friction behaviour of Magnesium(Mg) Metal Matrix Composite(MMC) reinforced with Silicon carbide(SiC) doped reduced graphene oxide (r-GO) nanosheets is carried over. In addition, a mathematical model is developed to predict the influence of various control factors of the Mg composites fabricated through Solvent-based powder metallurgy process. Herein SiC is doped with varying wt. % (10, 20, 30) into r-GO nanosheets and its effect over dry sliding wear is studied at constant control parameters like that of load (10N), sliding distance (1000m) and sliding velocity (1 m/s). Optimal parameter for specific wear rate (SWR) is attained by Taguchi method and the mathematical model was developed using Artificial Neural Network in order to understand the wear behaviour of developed MMC under varying parametric condition. Analysis of variance result reveals that wt.% of r-GO have major influence on SWR and sliding velocity have least effect. Occurrence of delamination wear could also be notified over the worn out surface.

Mechanical and tribological properties of LM13/TiO2/MoS2 hybrid metal matrix composite synthesized by stir casting

Abstract: This paper involves the fabrication of LM13/TiO2 (12 wt%)/MoS2 (3 wt%) hybrid metal matrix composite and unreinforced alloy using liquid metallurgy route and evaluation of mechanical properties and...

Influence of machining parameters on wire electrical discharge machining performance of reduced graphene oxide/magnesium composite and its surface integrity characteristics

Abstract: Taguchi coupled grey relation analysis is adopted to study the effects of machining parameters of Wire Electrical-Discharge Machining (WEDM) on magnesium metal matrix composite reinforced with Reduced Graphene Oxide(r-GO). An optimal combination of process parameter was expected to be finalized in this research to attain maximum Material Removal Rate (MRR) with a minimal surface roughness (Ra) value. The composite was fabricated through solvent based powder metallurgy route for varying percentage of r-GO. Experimental combination for WEDM of developed composite specimens were finalized to be L27 orthogonal array (OA) using Taguchi's method mainly based on the control factors namely reinforcement weight percentage (wt.%), pulse ON time (P1), pulse OFF time (P2) and wire feed rate (Wfd). ANOVA results revealed that wt.% and P1 are the most influencing parameters for MRR and Ra. Outputs scaleup that the developed regression model augments well with the experimental values. Using grey relation analysis (GRA) the optimal parameter was set and the final results obtained based on the optimal combination was found to be with a maximum MRR (18.38 mm3/min) and minimum Ra (3.29 μm). Traces of intermetallic formation are identified over the machined surface due to the action of machining parameters.

Assessment of the mechanical properties of aluminium metal matrix composite: A review:

Abstract: In the present scenario, composites are in huge demand in the industries due to their light weight, wear resistance, stiffness and high strength. The functional and structural properties were impro...

Titanium-based matrix composites reinforced with particulate, microstructure, and mechanical properties using spark plasma sintering technique: a review

Abstract: The interest for lightweight and high-temperature materials for critical innovative applications is expanding in numerous modern industries. Reinforcing ceramic particles with micro/nano-scale sizes into titanium alloys is distinguished, thereby increasing the hardness and wear resistance. Alternatively, reduction in particles sizes also helps in increasing the strength, ductility, and creep resistance of the reinforced materials. Nano-ceramic has significant improvement in mechanical properties of a material, which makes it practically a good reinforcement in metal composites. Recent advancement in nanotechnology area demands innovative improvement in metal matrix composite for critical and functional applications. The effects of micro/nanomaterial dispersion in the metal matrix composite are spoken about and the formation of unexpected interfacial reaction on these properties. Powder metallurgy is a process where powder materials are being compacted or sintered in the furnace with the perspective of accomplishing higher densities. Spark plasma sintering techniques have a favorable condition over other sintering methods since it tends to decrease the sintering time with high temperatures, attaining higher densities, microstructural evolution, and the tendency to improve the mechanical properties of the material. This review focuses on the fabrication and mechanical properties of titanium alloy strengthening with micro/nano-ceramics.

The influence of the pre-placed powder layers on the morphology, microscopic characteristics and microhardness of Ti-6Al-4V/WC MMC coatings during laser cladding

Abstract: Ti-6Al-4V/WC metal matrix composite (MMC) coatings provide an adequate solution for high wear resistance application of Ti-6Al-4V. Laser cladding process, which has been extensively researched as an advanced repairing and strengthening technology, is considered to be an important candidate to combine the ductile metal matrix and high surface properties. In this study, the powder-presetting laser cladding technology was employed to fabricate WC particles reinforced MMC coatings applying pre-placed pure WC powder layers and Ti-6Al-4V/WC powder layers, respectively. These experiments were performed to investigate the influence of the pre-placed powder layers on the Ti-6Al-4V/WC MMC coatings. The morphology, microscopic characteristics and microhardness of the coatings were scrutinized using optical microscopy, X-ray diffractometer, scanning electron microscopy and Vickers hardness tester. The experimental results show that the coatings fabricated from pre-placed Ti-6Al-4V/WC powder are enhanced more obviously in comparison with pure WC powder, which is related to the more uniform distribution of WC, smooth morphology of coatings and homogeneous distribution of microhardness.

Tribological characterization of Al6061/alumina/graphite/redmud hybrid composite for brake rotor application

Abstract: Dry sliding tribological characterization of redmud particle-reinforced Al6061/alumina/graphite hybrid metal matrix composite (RM-AlHMMC) was investigated as per ASTM G99-05 using pin on disc exper...

Manufacturing of a Metal Matrix Composite Coating on a Polymer Matrix Composite Through Cold Gas Dynamic Spray Technique

Abstract: In this work, the manufacturing through cold gas dynamic spray (cold spray or CS) of metallic composite coatings of Al-Al2O3 on organic composite substrates with thermoplastic PLA matrix and hemp fibers was studied. Alumina powders, with a mean diameter of 50 μm, were used blended with aluminum powders in three different weight concentration percentages (0, 15, 20, and 45%) as feedstock material in order to highlight and discuss the variations of the coating surface properties depending on the alumina percentage. The coatings were produced by using a low-pressure cold spray equipment. A detailed experimental campaign, including microstructural observations and confocal microscopy, was carried out to study the structure of the coatings. Moreover, the tribological behavior of the coatings was studied through both scratch test and pin-on-disk test. The experiments showed that a small addition of alumina improves the compactness of the coating and its resistance to scratch and wear behavior.

Microstructure characterization and maximization of the material removal rate in nano-powder mixed EDM of Al-Mg2Si metal matrix composite—ANFIS and RSM approaches

Abstract: Al-Mg2Si in situ composite is a new metal matrix composite (MMC) with numerous applications in different engineering fields. MMCs are considered difficult-to-cut materials due to the abrasive nature of the reinforcement (e.g., Mg2Si), hardness, and built-up edge. Hence, electrical discharge machining (EDM) is one of the alternative ways to machine Al-Mg2Si. With EDM, it is possible to machine conductive materials with different strength, temperature resistance, and hardness as well as produce complicated shapes, high-aspect ratio slots, and deep cavities with precise dimensions and good surface finish. The experiments in this study were designed by response surface methodology (RSM) and ANFIS was utilized to analyze the nano-powder mixed EDM (NPMEDM) of Al-Mg2Si in situ composite. The study represents the impacts of NPMEDM parameters on changes in microstructure and material removal rate (MRR). The results revealed that among all interactions, the current-voltage and current-pulse ON time interactions have the most significant effect on MRR. Moreover, current has most significant effect, followed by voltage, pulse ON time and duty factor. An analysis of the Al-Mg2Si microstructure demonstrated that current, pulse ON time, and voltage have remarkable impact on the microstructure, size of craters, and profile of the machined surface. Moreover, decrease in spark energy leads to less microstructural change and better surface finish.

Elucidation of the role of rotation speed and stirring direction on AA 7075-B4C surface composites formulated by friction stir processing:

Abstract: In the present research investigation, aluminum–boron carbide surface composites were fabricated using friction stir processing technique. Boron carbide powder particles were incorporated into AA 7...

Dry sliding wear behaviour of single and dual ceramic reinforcements premixed with Al powder in AA6061 matrix

Abstract: This work highlighted the preparation of a hybrid of AA6061/Al 2 O 3 /graphite composite by additionally incorporating Si 3 N 4 nanoparticles in the material system. The reinforcements were premixed with Al metal powder to improve their diffusion into the matrix during manufacturing of composites. The composites were manufactured by stir casting method. The pin on disc wear test was carried out as per ASTM G99 standard. Field emission scanning electron microscope (FESEM) and energy dispersive spectroscopy (EDS) analysis were conducted on worn out surface and subsurface of the composite specimens to determine the wear mechanism. From the results, it was found that the wear behaviour of Al powder premixed reinforcement was superior to unmixed reinforcements. The composites with dual ceramic reinforcement have shown lesser wear rate and coefficient of friction than composites with single ceramic reinforcement. Abrasive wear and grain structure refinement just beneath the worn out surface were noted in composites with Si 3 N 4 nanoparticles. Single ceramic reinforcement of Al premixed Al 2 O 3 was identified with abrasive wear, micro cuts and formation of mechanically mixed layer on the worn out surface. Single ceramic reinforcement of unmixed Al 2 O 3 exhibited abrasive wear and severe plastic deformation on worn out surface. Porosity, particle fracture and particle pull out were noticed in the subsurface of the composites with unmixed single ceramic reinforcement of Al 2 O 3 .

Characterization of dry sliding wear mechanisms of AA5083/B 4 C metal matrix composite

Abstract: Aluminium alloy is known to be a soft material with inadequate hardness, poor wear resistance and good castability; in order to improve its wear resistance, numerous researches have been conducted. This paper deals with the wear mechanisms of aluminium alloy (AA5083) composites reinforced with boron carbide (B4C) particles having 300 mesh size. The fabrication of aluminium metal matrix composite specimen by varying boron carbide in 5%, 10%, 15% and 20% of the weight of aluminium alloy was produced (composite-A, composite-B, composite-C and composite-D, respectively) by the stir-casting technique. The wear mechanisms of the developed metal matrix composites were studied at various parameters such as sliding distance (1000 m, 2000 m and 3000 m), load (30 N, 40 N and 50 N) and sliding velocity (1 m/s, 2 m/s and 3 m/s). The wear mechanisms of the prepared specimen (composites-A, B, C and D) were compared with each other under the same experimental condition on the pin-on-disc wear machine. The major findings in this paper are: the better wear resistance property of the developed metal matrix composites than that of the alloy used as matrix, the wear of composite has been linear and effortless prediction of the wear characteristics by the researchers.