Reinforced Silicon Carbide Research Articles

Microstructure Characterization, Mechanical and Wear Behavior of Silicon Carbide and Neem Leaf Powder Reinforced AL7075 Alloy hybrid MMC’s.

The demanding material quality criteria in the automotive and aerospace industries have recently had an impact on the development of lightweight aluminium alloys. The choice and application of metal-matrix composites as structural materials in this context are known to offer a variety of benefits. These benefits include the ability to combine high elastic modulus, toughness, and impact resistance; minimum sensitivity to change in temperature or thermal shock; durability of the surface is good; moisture absorption leads to the potential issue while minimum exposure which leads to environmental degradation; and improved fabricability with conventional metalworking equipment. Aluminium metal matrix composites (AMMCs) are a potential material for advanced structural, aviation, aerospace, marine, and defence applications, as well as for the automotive sector and other related fields, due to their outstanding combination of qualities. The stir casting procedure is used to create an aluminium metal matrix composite (AMMC), which is the most efficient way to do so. In this study, the aluminium alloy 7075 is strengthened using neem leaf powder and SiC. The Vickers hardness examination method is used to govern the hardness of hybrid composites. Eventually, the mechanical and tribological properties of the composites were assessed, and their relationship to the composites' matching microstructure and wear was addressed.

Micromechanics-Based Modeling of SiC/SiC Ceramic Matrix Composites and Structures

The behavior and response of ceramic matrix composites (CMCs), in particular silicon carbide fiber reinforced silicon carbide matrix (SiC/SiC), is affected by many factors such as variation of fiber volume fraction, residual stresses resulting from processing of the composites at high temperature, random microstructures, and the presence of matrix flaws (e.g., voids, pores, cracks etc.) as well as general material nonlinearity and heterogeneity that occurs randomly in a composite. Residual stresses arising from the phase change of constituents are evaluated in this paper and it is shown that they do influence composite strength and need to be properly accounted for. Additionally, the microstructures (location of fiber centers, coating thickness etc.) of advanced CMCs are usually disordered (or random) and fiber diameter and strength typically have a distribution. They rarely resemble the ordered fiber packing (square, rectangular, or hexagonal) that is generally assumed in micromechanics-based models with periodic boundary conditions for computational expediency. These issues raise the question of how should one model such systems effectively? Can an ordered hexagonal packed repeating unit cell (RUC) accurately represent the random microstructure behavior? How many fibers need to be included to enable accurate representation? Clearly, the number of fibers within an RUC must be limited to insure a balance between accuracy and efficiency. NASA’s in-house micromechanics-based code MAC/GMC provides a framework to analyze such RUCs for the overall composite behavior and the FEAMAC computer code provides linkage of MAC/GMC to the commercial FEA code, ABAQUS. The appropriate level of discretization of the RUC as well as the analysis method employed, i.e., Generalized Method of Cells (GMC) or High Fidelity Generalized Method of Cells (HFGMC), is investigated in this paper in the context of a unidirectional as well as a cross-ply laminated CMC. Results including effective composite properties, proportional limit stress (an important design parameter) and fatigue are shown utilizing both GMC as well as HFGMC. Finally, a few multiscale analyses are performed on smooth bar test coupons as well as test coupons with features such as open-hole and double notches using FEAMAC. Best practices and guidance are provided to take these phenomena into account and keep a proper balance between fidelity (accuracy) and efficiency. Following these guidelines can account for important physics of the problem and provide significant advantages when performing large multiscale composite structural analyses. Finally, to demonstrate the multiscale analysis framework, a CMC gas turbine engine vane structure is analyzed involving a progressive damage model.

Influence of Silicon Carbide and Graphite Reinforcements and T6 Aging Heat Treatment on the Fatigue Characteristics of AZ91D Magnesium Alloy

Influence of Silicon Carbide and Graphite Reinforcements and T6 Aging Heat Treatment on the Fatigue Characteristics of AZ91D Magnesium Alloy

Thermal Kinetics of Varying Weight Fraction of Silicon Carbide Reinforced Al–Zn–Mg–Cu Alloy Composite

Thermal Kinetics of Varying Weight Fraction of Silicon Carbide Reinforced Al–Zn–Mg–Cu Alloy Composite

Enhancing the Mechanical Properties of AZ31D Alloy by Reinforcing Nanosilicon Carbide/Graphite

Magnesium-based alloys were more prevalent in automobile applications owing to their mechanical properties, low mass, and density. However, its poor mechanical properties are restricting its applications. Therefore, the present study focuses on improving the mechanical properties of AZ31D alloy by reinforcing silicon carbide (SiC) and graphite (Gr) nanoparticles with weight fractions of 2%, 4%, and 6% using stir-casting technique. The microstructure analysis was performed using a scanning electron microscope. The elemental analysis was confirmed using energy-dispersive spectroscopy, and X-ray diffraction was used to study various phases in the nanocomposites. Further, the mechanical properties, such as microhardness, ultimate tensile strength, yield strength, and compression strength of the nanocomposites, were significantly improved by 53%, 59%, 62%, and 82%, respectively, as compared with base alloy.

Study of Mechanical Characteristics of Silicon Carbide Reinforced Zn-Mg Based Metal-Ceramic Composite

Study of Mechanical Characteristics of Silicon Carbide Reinforced Zn-Mg Based Metal-Ceramic Composite

Investigations on the effect of ultrasonic vibration on fibre fracture and removal mechanism in cutting of fibre reinforced silicon carbide ceramic matrix composites

To clarify the effectiveness of ultrasonic vibration-assisted cutting (UVAC) technology for improving the surface quality of FRCMCs-SiC, it is necessary to have a deep understanding of fibre fracture and removal mechanism of UVAC. The paper focuses on the feasibility and effect of UVAC technology on improving the machined surface quality of FRCMCs-SiC combining finite element model (FEM). The results show that applying ultrasonic vibration (UV) along the cutting direction, whether in the micro brittle fracture regime or the macro brittle fracture regime, is beneficial to reduce the cutting force, the machined surface roughness and the depth of the subsurface damage. When UV is applied perpendicular to the cutting direction, it can promote fibre fracture in the macro brittle fracture regime and reduce the depth of the subsurface damage, but deteriorate the machined surface quality in the micro brittle fracture regime.

Microstructural tailoring, mechanical and thermal properties of SiC composites fabricated by selective laser sintering and reactive melt infiltration

Poor flowability of printable powders and long preparation cycles are the main challenges in selective laser sintering (SLS) of chopped carbon fiber reinforced silicon carbide composites (SiC composites) with complex structures. In this study, we develop an efficient and novel processing route in the fabrication of lightweight SiC composites via SLS of phenolic resin (PR) and C_f powders with the addition of α-SiC particles combined with one-step reactive melt infiltration (RMI). The effects of α-SiC addition on the microstructural evolution of the C_f/SiC/PR printed bodies, C_f/SiC/C green bodies, and derived SiC composites were investigated. The results indicate that the added α-SiC particles play an important role in enhancing the flowability of raw powders, reducing porosity, increasing the reliability of the C_f/SiC/C green bodies, and contributing to improving the microstructure homogeneity and mechanical properties of the SiC composites. The maximum density, flexural strength, and fracture toughness of the SiC composites are 2.749±0.006 g×cm⁻³, 266±5 MPa, and 3.30±0.06 MPa·m^1/2, respectively. The coefficient of thermal expansion (CTE) of the SiC composites is approximately 4.29×10⁻⁶ K⁻¹ from room temperature (RT) to 900 °C, and the thermal conductivity is in the range of 80.15-92.48 W·m⁻¹·K⁻¹ at RT. The high-temperature strength of the SiC composites increase to 287±18 MPa up to 1200 °C. This study provides a novel as well as a feasible tactic for the preparation of high-quality printable powders as well as lightweight, high strength, and high thermal conductivity SiC composites with complex structures by SLS and RMI.

Tailoring friction and wear properties of titanium boride reinforced silicon carbide composites

Besides continuous progress in designing superior composition for silicon carbide (SiC) ceramics, a thorough understanding of the relation of material composition with contact surface characteristics is necessary to cater varied requirements of friction and wear for tribological applications. In the present study, the friction and wear behaviour of spark plasma sintered SiC ceramics in sliding contacts against SiC is explained in terms of titanium boride (TiB2) addition (0–30 vol%) and sliding load (5–15 N). Abrasion, fracture, and grain pull-out are observed on worn surfaces. X-Ray photoelectron spectroscopy results confirm the absence of dominant tribo-chemistry and Raman spectroscopy analysis confirms tensile stress accumulation on wear track. The microstructure and mechanical properties strongly influenced the wear resistance of the composites, while the roughened contact with hard debris increased friction. A combination of low wear rate (2.5 X 10−6 mm3/Nm) and high COF (0.47) obtained at 5 N load for SiC-20 vol% TiB2 composite. Experimental wear results are in agreement with the estimation using lateral fracture model. Results from the present study are believed to be useful in designing new generation SiC based composites for high friction and low wear applications.

Effects of Multi Walled Carbon Nanotube and Silicon Carbide Reinforcement on Wear Performance in Zinc-Aluminium Alloys

In this study, hybrid composite materials were produced by adding SiC (Silicon carbide) and MWCNT (Multi-walled carbon nanotube) to Zinc-Aluminium (ZA40) alloy, sintering under 700 MPa pressure and 500 °C using mechanical alloying and hot press technique. Hybrid samples were produced with 2% MWCNT constant and SiC ratio 1-2-3 and 4% by weight in the mixtures. The mechanical properties such as hardness and porosity of the produced hybrid composite materials were determined and their wear properties were investigated by traveling 300 m using 10 and 20N loads under 300 rpm constant speed in a ball-on-disc wear test setup. The obtained internal structure and wear surface images showed that the SiC and MWCNT reinforcement contributed significantly to the wear resistance of the hybrid composites, and in the SEM analyzes of the worn surfaces, there was a transition from abrasive wear to adhesive wear in the wear mechanism.

Mechanical Study of Aluminium -Silicon Carbide -Tungsten Carbide Hybrid Composite Synthesized Through Powder Metallurgy Technique

In this study, powder metallurgy is used to create hybrid metal matrix alloys made of aluminium-silicon carbide -tungsten carbide. Aluminium metal matrix composites are now vastly used in automobile industry due to superior qualities, such as improved corrosion protection, high ductility, and strength to weight ratio is also high too. With individual silicon carbide reinforcement, weight percentages of 5%, 10%, 15% and 20% of composite samples are created using the powder metallurgy method. The manufactured composite samples' physical and mechanical characteristics were examined. By using two analysis(SEM and XRD), aluminium, siliconcarbide, and tungsten carbide are found. Aluminium -10%Silicon Carbide -10%Tungsten Carbide reinforcement was determined to have a higher ultimate tensile strength (UTS) of 263 MPa as well as yield strength (YS) of 202 MPa for composite. Aluminium -10%Silicon Carbide -15 %Tungsten Carbideand Aluminium -10%Silicon Carbide -20%Tungsten Carbide reinforcement showed that the intermetallic specimenis formed(eg: Al2Cu), which causes a drop in the UTS and YS of manufactured samples. Hybrid composites made of Aluminium, silicon carbide10%, and 10% WC had the greatest combination of mechanical properties. Aluminium, silicon carbide, and WC particles can be seen in the XRD images. Aluminium-silicon carbide 10%-15% WC and aluminium-silicon carbide 10%-20% WC were found to have intermetallic phases present as well. SEM as well as EDS mapping were verified, reinforcements for the 15% and 20% WC reinforcements were distributed uniformly and formed into agglomerations. In comparison to monolithic aluminium, the results revealed that the aluminium-silicon carbide 10%- 10% WC has superior mechanical properties.

Microstructural evolution of polymer derived SiC ceramics and SiC/SiC composite under 1.8MeV electron irradiation

Continuous silicon carbide fiber reinforced silicon carbide matrix composites (SiC/SiC) are promising candidate materials for nuclear applications. Herein, SiC ceramics and SiC/SiC composite were prepared by a polymer deriving method, and irradiated using a 1.8 MeV electron beam. The microstructural evolution and radioluminescence performance were investigated, and the results showed that the SiC ceramics and the SiC/SiC composite all exhibited evident amorphization after the electron irradiation. In addition, the radioluminescence intensity of the SiC ceramics and the SiC/SiC composite was too low owing to the self-absorption of the free carbon in the polymer derived SiC ceramics.

Characterization and corrosion behavior of composites reinforced with ZK60, AlN, and SiC particles

In this paper, microstructure, mechanical, immersion and potentiodynamic corrosion behaviours of extruded ZK60 matrix composites reinforced with forty-five µm 15% silicon carbide (SiC) particles and aluminium nitride nanoparticle (AIN) (0.2–0.5% 760 nm) were investigated. The SiC and AlN mixtures, which are the reinforcing elements of the composites, were first mixed with magnesium powder as the main alloy, then pressed under a pressure of 450 MPa and sintered at 420 °C. Second, the sintered compacts are placed in the ZK60 alloy matrix at the semi-solid melting temperature, and the melt is mixed mechanically. After the melts are mixed for 30 min and a homogeneous mixture is obtained, the mixtures are poured into metal moulds and composite samples are produced. After homogenization for 24 h at 400 °C, the composite samples were extruded at 300 °C with an extrusion ratio of 16:1 and a piston speed of 0.3 mm/s. Then, microstructure characterization of all composite samples was performed and potentiodynamic and immersion corrosion behaviours were analyzed in 3.5% NaCl solution. It was seen that the corrosion resistance increased depending on the percentages of SiC and AlN reinforcement elements in the matrix. As a result, it was seen that the potentiodynamic corrosion resistance of reinforced ZK60 + 15% SiC (ZK60SiC15), ZK60 + 15% SiC + 02AIN (ZK60SiC15AlN0.2) and ZK60 + 15% SiC + 0.5% AIN (ZK60SiC15AlN0.5) compounds increased by 1.6, 1.8 and 3.5 times compared to the unreinforced ZK60 alloy. The immersion corrosion rates were calculated as 2090.73, 1748.19, 1479.84 and 1397.79 (mg/year) for the unreinforced ZK60, ZK60SiC15, ZK60SiC15AlN0.2 and ZK60SiC15AlN0.5 reinforcements, respectively. As a result of the SEM and elemental spectrum response analysis of the corrosion surfaces, the presence of a layer rich in Si-O elements on the surface of the AlN + SiC reinforced composites enhanced corrosion resistance. Additionally, the formation of the Mg2Si intermetallics in the structure of the SiC reinforced composites improved corrosion resistance, according to the XRD results.

Investigations on Silicon Carbide Reinforced High Entropy Alloy (CoCrNiMnFe) matrix Composites Produced by Powder Metallurgy Process

Investigations on Silicon Carbide Reinforced High Entropy Alloy (CoCrNiMnFe) matrix Composites Produced by Powder Metallurgy Process

Evaluating the dynamic characteristics of microwave-casted metal matrix composite material by using experimental modal analysis

This paper proposes an experimental modal analysis technique to measure the dynamic characteristics of microwave-casted metal matrix composite (MMC). To fabricate MMC, silicon carbide (SiC) is reinforced into the SS202 matrix. The damping capacities of MMC at different reinforcements of SiC powder such as 0.05%, 0.1% and 0.2% are measured through experimental modal analysis. The main objective is to study the effect of reinforcement on the damping capacity of SS202. The domestic microwave oven with the specification of 2.45 GHz and 900 W power is used to cast the MMC material. The graphite split mold is used for in-situ microwave casting. The mechanical characterization in terms of micro-hardness and scanning electron microscopy (SEM) of MMC is also examined. From SEM imagining, complete diffusion of the SiC in SS matrix is observed for 0.05% of SiC reinforcement; however, incomplete diffusion is observed for 0.1% and 0.2% of SiC reinforcement. It is observed that the hardness of the SS202 is increasing with the decrease in the percentage of SiC powder. The experimental modal analysis is carried out by using SO Analyzer. The response model in terms of the frequency response function (FRF) curve is measured when the specimen is excited at impact excitations. The half power bandwidth method is used to calculate the damping factor of the material from the measured FRFs. It is observed that the damping capacity increases with the increase in percentage of SiC in SS202. SS202 with 0.05%, 0.1% and 0.2% SiC have the hardness value of 155.33 HV, 107.33 HV and 58.33 HV, respectively.

Fiber orientation effects on grinding characteristics and removal mechanism of 2.5D Cf/SiC composites

Carbon fiber reinforced silicon carbide (Cf/SiC) composites are widely used in aerospace for their excellent mechanical properties. However, the quality of the machined surface is poor and unpredictable due to the material heterogeneity induced by complex removal mechanism. To clarify the effects of fiber orientation on the grinding characteristics and removal mechanism, single grit scratch experiments under different fiber orientations are conducted and a three-phase numerical modelling method for 2.5D Cf/SiC composites is proposed. Three fiber cutting modes i.e., transverse, normal and longitudinal, are defined by fiber orientation and three machining directions i.e., MA (longitudinal and normal), MB (longitudinal and transverse) and MC (normal and transverse), are selected to investigate the effect of fiber orientation on grinding force and micro-morphology. Besides, a three-phase cutting model of 2.5D Cf/SiC composites considering the mechanical properties of the matrix, fiber and interface is developed. Corresponding simulations are performed to reveal the micro-mechanism of crack initiation and extension as well as the material removal mechanism under different fiber orientations. The results indicate that the scratching forces fluctuate periodically, and the order of mean forces is MA > MC > MB. Cracks tend to grow along the fiber axis, which results in the largest damage layer for transverse fibers and the smallest for longitudinal fibers. The removal modes of transverse fibers are worn, fracture and peel-off, in which normal fibers are pullout and outcrop and the longitudinal fibers are worn and push-off. Under the stable cutting condition, the change of contact area between fiber and grit leads to different removal modes of fiber in the same cutting mode, and the increase of contact area results in the aggravation of fiber fracture.

Material Removal Behavior of Ultrasonic Vibration Helical Grinding of SiCf/SiC Composites

Abstract To reveal the material removal mechanism of silicon carbide fiber reinforced silicon carbide ceramic matrix (SiCf/SiC) composites during the ultrasonic vibration helical grinding (UVHG) of hole-making process, a hole-making experiment of UVHG was conducted, and the contact behavior between a grain and different components in the SiCf/SiC was analyzed. The evaluation index of the hole wall quality Cw which comprehensively considers the overall level and local defects of surface quality was proposed, while the evaluation index of the hole exit quality Ce which comprehensively considers the area and depth of edge chipping was proposed too. The results show that the periodic changes of the fiber cutting angle θ will lead to different fracture mechanisms of the fibers and the interfaces, so the surface topography will change regularly. The brittle fracture of the matrixes under different process parameters is different, so the surface topography is different. The quality evaluation indexes Cw and Ce are highly reliable. Within the experimental parameters, selecting a smaller pitch, a smaller helical feed rate, and an appropriate ultrasonic amplitude can obtain better hole-making quality.

Study on the Optimization of Surface Modification Processing of SiCp and Tribological Properties of AA6061-SiCp based Composites

The unique property combination of Al/SiCp based composites make them very attractive for applications in automotive and aerospace industries. The choice of composite materials for these applications is directly influenced by their inherent properties which are a function of the processing route employed. Like other processing parameters, surface modification treatment of SiCp can play a major role in determining the properties of Al/SiCp composites. In this study, the effects of SiC reinforcement (wt%) fractions (SRF), surface oxidation temperature (SOT) and preheating temperature (PT) parameters on the wear and friction properties of stir-cast Al-SiCp based composite were investigated. Experimental data and models are generated and analyzed based on a three-factors-five-level central composite design (CCD) and analysis of variance (ANOVA). The empirical models developed for wear rate and coefficient of friction (COF) considering the pre-processing parameters adequately predicts the Al-SiCp properties with the silicon carbide reinforcement (wt%) fraction emerged as the most influencing factor. The goal of the optimization process is to minimize both wear rate and COF. For wear rate, SRF at 44.49 % contribution had the most influence on wear rate, while SOT and PT had 0.65 % and 1.03 % influence on wear rate respectively. For COF, SRF also showed highest influence of 35.48 % on COF, while SOT and PT had 0.047% and 2.66% influence on COF respectively. From the optimization analysis, the set of conditions that simultaneously optimizes both wear rate and COF are 10% SiC weight (SW), 1234°C surface oxidation temperature (SOT), and 376.2°C preheat temperature (PT). The resulting responses at this optimized condition are minimum wear rate of 0.11 mm3/m and COF of 0.11 with a confidence and desirability level of 1.

Heat transfer mechanism of fiber reinforced composites processed by pulsed laser

The generate principle and suppression method of thermal effect of silicon carbide fiber reinforced silicon carbide (SiC/SiC) in processing of nanosecond lasers with infrared band (fiber laser with maximum power of 20 W), visible light band (solid-state laser with maximum power of 4 W) and ultraviolet band (fiber laser with maximum power of 7 W) were studied. Firstly, the three-dimensional temperature field model was established to simulate the ablation process of SiC/SiC composites by pulsed laser. It was found that the SiC fiber bundle has a great influence on the energy distribution acting on the SiC/SiC composites, and the heat tends to transfer along the longitudinal direction of the fiber bundle. Secondly, nanosecond lasers with wavelengths of 1064, 532, and 355 nm were used for processing experiments in air and water environments respectively. The scanning power was set to 1.5–3 W, and the morphology quality of the microstructure after processing was analyzed. The results showed that: As the wavelength increases, the energy value of the pulsed laser increases, the oxidation and melt accumulation are more obvious, and the heat affected zone (HAZ) is larger. Besides that, the water solution can take away part of the heat and debris during the processing, reduce the accumulation of the melt, effectively avoid the processing damage caused by the thermal effect, and improve the quality of the microstructure.

An examination of microstructure, microhardness and tribological properties of ceramic reinforced bronze matrix composite materials

In order to obtain better mechanical properties in a bronze alloy, it is important to produce new materials by adding reinforcements and to offer these materials to the industry. In this study, bronze matrix (Cu10Sn) materials were reinforced with boron carbide (B4C) and silicon carbide (SiC) ceramic materials by using the mechanical alloying method. New composite materials were produced by powder metallurgy method by adding ceramic reinforcement (B4C and SiC) at 1, 2, 4 and 8 weight ratios to Cu10Sn alloy, which is the main matrix material. The obtained composite materials examined in terms of structural, microhardness and wear resistance. Coefficient friction, specific wear rate and volume loss rates under 5N, 10N, and 15N loads were examined for the samples produced. When the applied microhardness and wear behaviors were examined, it was generally seen that the hardness and wear behaviors were improved with the added reinforcement ratios. In line with the examinations made, based on the hardness and wear processes applied to the materials consisting of the bronze matrix of the reinforcement material, it was observed that the most appropriate results were obtained from composite materials (Alloy 4 and Alloy 8), which contain 4% B4C and SiC reinforcement.