Reinforced Silicon Carbide Research Articles

High-temperature flexural strength of I-CVI processed Cf/SiC composites with variable interphases

The effect of single-layer pyrocarbon (PyC) and multilayered (PyC/SiC)n=4 interphases on the flexural strength of un-coated and SiC seal-coated stitched 2D carbon fiber reinforced silicon carbide (Cf/SiC) composites was investigated. The composites were prepared by I-CVI process. Flexural strength of the composites was measured at 1200 °C in air atmosphere. It was observed that irrespective of the type of interphase, the seal coated samples showed a higher value of flexural strength as compared to the uncoated samples. The flexural strength of 470 ± 12 MPa was observed for the seal coated Cf/SiC composite samples with multilayered interphase. The seal coated samples with single layer PyC interphase showed flexural strength of 370 ± 20 MPa. The fractured surfaces of tested samples were analyzed in detail to study the fracture phenomena. Based on microstructure-property relations, a mechanism has been proposed for the increase of flexural properties of Cf/SiC composites having multilayered interphase.

Investigation on fiber fracture mechanism of c/sic composites by rotary ultrasonic milling

With wide application of continuous carbon fiber reinforced silicon carbide matrix (C/SiC) composites, machining damages have been paid more and more attention. Due to prominent anisotropy and heterogeneity, fiber damages affect the service performance of C/SiC parts directly. Surface quality is closely related to fiber fracture mechanism. This paper emphatically analyzed fiber removal process of rotary ultrasonic milling (RUM) of C/SiC composites. A calculation method for fiber fracture stress based on ultrasonic vibration was presented. High-frequency, low-amplitude oscillation varied fiber cutting angle and increased fiber shear stress through deflecting friction form the axial section to radial section of fiber. It promoted shear fracture mode to dominant removal mechanism greatly. The proportion of fiber cutting angle under shear fracture mode was enlarged by 30%. Then both RUM and conventional milling (CM) C/SiC tests were carried out. The principle of surface quality improvement during rotating ultrasonic milling was presented. Experimental results showed that fiber cutting angle affected C/SiC surface morphology directly. Surface of RUM had better machining quality with less delamination, fiber-matrix debonding length and fiber pulling-out damage. Its surface roughness Sa values were reduced by 26.8% and 40.6% during fiber forward cutting and backward cutting, respectively. It proved the rationality and effectiveness of rotary ultrasonic milling C/SiC composites.

A Review on Mechanical and Tribological Properties of Graphite, Silicon Carbide and Pineapple Leaf Fibre Reinforced Polymer Composites

This paper presents a review of the mechanical and tribological properties of a reinforced polymer matrix composite of graphite, Silicon Carbide (SiC), and Pineapple Leaf Fibre (PALF). Also investigated are the factors influencing the properties such as type and variety of natural fibres, type of matrix materials, fibre length and their orientation, surface treatment to improve the interfacial property of fibre, type of graphite, and its particle size. Also discussed is the tribological property of SiC and its application for improving the wear property of the composite. It is hoped that this review article would be useful to those working in the domain of polymer matrix composites with SiC, graphite and natural fibre leaves such as pineapple leaf. How to cite this article: Mahadevareddy, Adveesh B, Hiremath VK. A Review on Mechanical and Tribological Properties of Graphite, Silicon Carbide and Pineapple Leaf Fibre Reinforced Polymer Composites. J Adv Res Mfg Mater Sci Met Engr 2020; 7(3): 11-22. DOI: https://doi.org/10.24321/2393.8315.202004

Characterization and Properties of Silicon Carbide Reinforced Ni-10Co-5Cr (Superalloy) Matrix Composite Produced Via Powder Metallurgy Route

In this investigation, Ni-Co-Cr-SiC composites with various weight percentages were manufactured via powder metallurgy (PM) route. The compositions of the composites are Ni-10%Co-5%Cr, Ni-10% Co-5%Cr-4%SiC, Ni-10%Co-5%Cr-8%SiC and Ni-10%Co-5%Cr-12%SiC. The powders were mixed using planetary ball mill for a period of 10 h. The ball milled powders were subjected to X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) analysis. By utilizing 150 kN hydraulic press with appropriate punch and die the ball milled powders were compacted as a cylindrical billets. The green compacts were sintered in a tubular furnace at two different temperatures 1000 °C and 1200 °C for3 h. The characterization examination namely XRD, SEM and Energy Dispersive Analysis (EDAX) was made on the sintered samples. Unreinforced Ni-Co-Cr exhibits higher sinterability at both sintering temperature. The sintering temperature and reinforcement weight percentage effect on the mechanical properties and corrosion behavior of the composites were examined. From these investigations, the mechanical properties and corrosion resistance of the composites were enhanced while increasing the sintering temperature and SiC weight percentage in the Ni-Co-Cr super alloy matrix.

Comparison studies on mechanical and wear behavior of Stir Cast Al-SiC-B4C metal matrix composites

This paper studies the surface tribology and mechanical properties of AA6061 graded aluminum alloy matrix composite, reinforcing Silicon Carbide and Boron Carbide. In this work, the AA6061 graded aluminum alloy is reinforced with 3%, 6%, 9% (By weight) of B4C with constant 5% (By weight) of SiC under stir casting and producing three test samples A, B and, C respectively. The Samples were subjected to wear test, tensile test, impact test, and hardness test calculating wear loss, wear rate, coefficient of friction, ultimate tensile strength, impact strength, and brinell hardness. From analyzing the results from the test conducted, it is inferred that maintaining the optimum B4C composition between 3% and 6% in Al-SiC produces better mechanical properties and wear resistance.

Instrumentation Based Microstructural Characterization of the Friction Stir Welded SiC/B4C Aluminium Metal Matrix Composites and Optimization of Governing Process Parameters

Aluminium Metal Matrix Composites reinforced with particulate silicon carbide and Boron Carbide reinforcements have demanding applications in aerospace and automotive domains. With a lack of sufficient literature on this composite combination and emerging demands, it is highly essential to understand their weldability and material characteristics. Friction Stir Welding is a feasible choice for joining of Aluminium Metal Matrix Composites over the conventional fusion welding owing to narrow Heat Affected Zone and minimized Intermetallic Compound formation at the weld interface. In this work, AA6061 matrix composite plates are fabricated with a varying weight percentage of particulate SiC and B4C reinforcements using powder metallurgy process. The study mainly focusses on the tensile strength, hardness and microstructural properties of composite plates joined using Friction Stir welding subjected to a constant load of 8KN at three-level process parameters experimental design of varying spindle speed, weld speed and plunge depth. The outcomes reveal sufficient information on the microstructural analysis of the weldments and the subsequent effects on the material strength. Followed by, statistical process parameter optimization is performed to improve the tensile properties of the weldments and the results are experimentally validated. The study confirms the feasibility and applicability of FSW in joining Al-MMCs.

Influence of silicon carbide and porcelain on tribological performance of Al6061 based hybrid composites

The impact of silicon carbide (5 wt%) and porcelain (1.5–6.0 wt%) reinforcements on mechanical and tribological features of Al-based hybrid composite (manufactured by metal stir casting) is investigated. A pin-on-disc tribometer was used for experiment and SEM for the characterization of wear for different operating conditions. The hardness of the hybrid composites enhanced approximately by 57% with an increment in porcelain particulates from 1.5 to 6 wt%. However, the wear loss and average coefficient of friction decrease when the porcelain content was added and was found to be minimum at 4.5 wt% porcelain. Hence, the presence of 4.5 wt% porcelain in the Al6061/5SiC hybrid composites produces the best wear properties.

C/C‐SiC component for metallic phase change materials

AbstractThanks to their high energy density and thermal conductivity, metallic Phase Change Materials (mPCM) have shown great potential to improve the performance of thermal energy storage systems. However, the commercial application of mPCM is still limited due to their corrosion behavior with conventional container materials. This work first addresses on a fundamental level, whether carbon‐based composite‐ceramics are suitable for corrosion critical components in a thermal storage system. The compatibility between the mPCM AlSi12 and the Liquid Silicon Infiltration (LSI)‐based carbon fiber reinforced silicon carbide (C/C‐SiC) composite is then investigated via contact angle measurements, microstructure analysis, and mechanical testing after exposure. The results reveal that the C/C‐SiC composite maintains its mechanical properties and microstructure after exposure in the strongly corrosive mPCM. Based on these results, efforts were made to design and manufacture a container out of C/C‐SiC for the housing of mPCM in vehicle application. The stability of the component filled with mPCM was proven nondestructively via computer tomography (CT). Successful thermal input‐ and output as well as thermal storage ability were demonstrated using a system calorimeter under conditions similar to the application. The investigated C/C‐SiC composite has significant application potential as a structural material for thermal energy storage systems with mPCM.

Optimization and Effect of Reinforcements on the Sliding Wear Behavior of Self-Lubricating AZ91D-SiC-Gr Hybrid Composites

This article statistically investigates the effect of various parameters such as material factors: silicon carbide (SiC) fraction, graphite (Gr) fraction and mechanical factors: normal load, sliding distance and speed on the sliding wear rate of self-lubricating AZ91D-SiC-Gr hybrid magnesium composites. The self-lubricating hybrid composites were fabricated using advanced vacuum assisted stir casting process. The sliding wear tests have been performed under dry conditions on pin-on-disc tribometer at 10-50 N loads, 1-3 m/s sliding speed and 1000-2000 m sliding distance. It has been examined that hybrid composites yielded improved wear resistance with reinforcement of SiC and solid lubricant graphite. ANOVA and signal-to-noise ratio investigation indicated that applied load was the most critical factor influencing the wear rate of fabricated hybrid composites followed by sliding distance. Further, the AZ91D/5SiC/5Gr hybrid composite has exhibited the best wear properties. From the SEM and EDS analysis of worn surfaces, delamination was confirmed as the dominant wear mechanism for AZ91D-SiC-Gr hybrid composites.

Microstructural studies on aluminium metal matrix composite (Al7075-SiC) fabricated through stir casting process

In the present work Al7075 metal matrix reinforced with silicon carbide (SiC) powder is fabricated through stir casting route. Metal matrix composites were manufactured by altering percent weight fraction of silicon carbide powder as 5% & 7.5% by weight with average particle size of 50 µm. Microstructural evaluation and Vickers microhardness studies on stir casted Aluminium 7075 alloy which has silicon carbide (SiC) reinforcement are reported in current paper. After stir casting of composites, manufactured composite samples are examined by using optical microscope and scanning electron microscope (SEM) in order to study distribution SiC particles in aluminium matrix. The microstructural observations on metal matrix composites have reported the presence of SiC reinforcement in the matrix which are very much fairly distributed into the matrix phase. Also it can be seen that there is little clustering of SiC particles in Al7075 matrix and porosity in manufactured composites. It is also been found that microhardness of aluminium metal matrix composites was improved with increment in reinforcement content.

Tensile Fractography of Artificially Aged Al6061-SiC+B<sub>4</sub>C Hybrid Composites

In the current work Al6061 hybrid composites reinforced with Silicon Carbide (SiC) and Boron Carbide (B4C) were studied for improvement in hardness and behavior of fracture surface after artificial aging. It was found that after aging at 100 and 200 OC, presence of SiC and B4C particles in the Hybrid Al6061 Matrix Composites showed substantial improvement in hardness compared to that of the base alloy. Behavior of fracture mechanism after tensile strength have been discussed to conclude the factors which impact the mechanism of crack growth. Presence of SiC and B4C reinforcement particulates and artificially aged at 100°C for Al6061-SiC+ B4C hybrid metal matrix composite shows enhancement in hardness by 180% and tensile strength by 80% due to the presence of finer secondary solute rich intermetallic phases of alloying elements. Fractography analysis displays particle interface failure and combination of brittle and ductile mode of failure.

Effect of shear strain rate on interlaminar shear behavior of 2D-C/SiC composites: A damage transition from notch ends initiation to gauge section initiation

Two-dimensional carbon fiber reinforced silicon carbide composites (2D-C/SiCs) exhibit excellent mechanical properties at high temperature. However, the weak interfacial performance limits range of their applications. In the present work, interlaminar shear strength (ILSS) of 2D-C/SiC was investigated. By using an industrial camera and an acoustic emission (AE) detection system, quasi-static tests at the shear strain rates from 10−5/s to 10−3/s were conducted. Strain contours revealed the damage evolution process. Peak frequencies of AE signals were clustered into three groups, corresponding to matrix damage, interfacial debonding and fiber fracture. Dynamic tests at the shear strain rates of 200/s and 600/s were conducted using a modified split Hopkinson bar (SHPB). The dynamic deformation phenomenon was captured by a high-speed camera. The high-speed images and digital image correlation (DIC) strain contours revealed the damage initiation under dynamic loading. Damage morphologies were observed by a scanning electron microscope (SEM). The real-time images and damage morphologies explained the mechanisms of shear strain-rate effect on ILSS. The proposed experimental method elicited a fresh perspective on designing dynamic interlaminar shear experiments. Moreover, the interlaminar shear performance over a wide range of shear strain rates enhanced our understanding of the strain-rate sensitivity of compressive strength and tensile strength of 2D-C/SiCs.

Machine Learning-Based Erosion Behavior of Silicon Carbide Reinforced Polymer Composites

The machine learning methodology is gaining immense exposure as a potential methodology for solving and modelling the machining behaviour of advanced materials. The present paper deals with the application of machining learning approach in analyzing and predicting the effect of reinforced silicon carbide (SiC) particle size on the erosion behaviour of silicon carbide reinforced polymer composites. L27 orthogonal array was designed based on Taguchi’s methodology to execute the experiments. Support vector machine (SVM) and multi-linear regression (MLR) approach were coupled with Taguchi’s methodology to validate obtained optimized response characteristics. These machine learning-based SVM and MLR models are adopted to analyze the absurdity among obtained experimental results and predicted response. Out of 27 experimental runs based on experimental design, 19 experimental runs were selected for training models whereas 08 models were selected for the testing phase. Impingement angle, workpiece reinforcement, standoff distance and slurry pressure were used as input process parameters, whereas material loss was observed as response characteristics. The kernel functions, i.e. Pearson VII based universal kernel (PUK) and radial based function (RBF) kernel were used with machine learning models to obtain the best performing machine learning approach in predicting erosion behaviour of polymer composites.

Effect of CNT impregnation on the mechanical and thermal properties of C/C-SiC composites

The present study investigates the effect of additional carbon source, in the form of carbon nanotubes (CNTs), on mechanical and thermal properties of carbon fiber reinforced silicon carbide (C/C-SiC) ceramic matrix composites (CMC) produced by liquid silicon infiltration (LSI) technique. The CNTs used in this study were impregnated into the C/C preforms before the liquid silicon infiltration stage. The results showed that the addition of excess carbon to the C/C preforms in the form of CNTs enhanced Si infiltration efficiency significantly resulting in C/C-SiC composites with higher density and microstructural uniformity. Accordingly, the addition of CNTs improved the flexural strength of the composites by 40% with respect to no-CNT-containing composites due to a lower amount of residual porosity and additional reinforcement effect of the unreacted CNTs. The thermal conductivity of the resulting C/C-SiC composites has been also increased by 31% and 18% parallel and perpendicular to the carbon fiber–woven fabric surface, respectively, by CNT addition.

Damage monitoring of carbon fiber reinforced silicon carbide composites under random vibration environment by acoustic emission technology

Carbon fiber-reinforced silicon carbide (C/SiC) composites are widely used in high-temperature thermo-structural applications. They are subjected to extreme loading conditions, such as random vibrations, which are likely to damage the structure. Structural micro-damage identification during vibration is very difficult, owing to the randomness of the environmental vibration and the complicated response it causes in structures. This study aims to determine a method for monitoring the damage properties of a C/SiC structure under a random vibration environment using acoustic emission (AE) technology. First, a pencil break experiment is conducted to verify the feasibility of the AE technology. Then, an AE monitoring experiment of the structural damage in a vibration environment is systematically conducted. Two types of experiments are designed for simulating the damage formation process inside the structure. In addition, the parameter characteristics of typical AE signals in the random vibration test are analyzed, and the relationships between the AE signal parameters and vibration loading are obtained. Lastly, the different stages of material damage development and damage types in each stage are provided to reveal the damage evolution processes of C/SiC composites. The results indicate that AE technology can be effectively applied to investigate the damage behaviors of C/SiC composites in random vibration environments.

Revealing thermal ablation mechanisms of C/SiC with in situ optical observation and numerical simulation

Structural ceramics such as C/SiC (carbon fiber reinforced silicon carbide) are of great importance for high temperature applications, where thermal ablation could occur and impair the structural integrity. Here we adopt in situ and real time optical visualization technique and numerical simulation to study the thermal ablation mechanisms of C/SiC subjected to oxyacetylene flame. The in situ optical setup captures the real time surface evolution at temperatures up to 1800℃, demonstrating clearly the formation of surface gas bubble, the flowing and merging process of liquid SiO2, which are later well reproduced and explained by the numerical simulation. Four different surface ablation regions on the sample subjected to thermal ablation have been identified by the captured images and flow field streamlines, which reveal the distribution and flow mechanism of SiO2 droplets on the C/SiC surface.

Remaining Useful Strength (RUS) Prediction of SiCf-SiCm Composite Materials Using Deep Learning and Acoustic Emission

Prognosis techniques for prediction of remaining useful life (RUL) are of crucial importance to the management of complex systems for they can lead to appropriate maintenance interventions and improvements in reliability. While various data-driven methods have been introduced to predict the remaining useful life (RUL) of machinery systems or batteries, no research has been reported on the remaining useful strength (RUS) prediction of silicon carbide fiber reinforced silicon carbide matrix (SiCf-SiCm) materials with pivotal role in its potential usage as a structural material in nuclear reactors and turbine engines. Knowledge of its degradation process is of the utmost importance to the manufacturers. For this purpose, two approaches based on the machine-learning techniques of random-forest (RF) and convolutional neural network (CNN) are proposed to predict the RUS of SiCf-SiCm using only acoustic emission (AE) signals generated during the material’s stress applying process. Experimental results show that the CNN models achieved better predictive performance than the RF models but the latter with expert-engineered features achieves better prediction for AE signals in the early stage of degradation. Additionally, our results demonstrate that both models can correctly predict the SiCf-SiCm RUS as evaluated by our robust testing method from which the best average root mean square error (RMSE) and Pearson correlation coefficient of 3.55 ksi units and 0.85 were obtained.

Mechanical Behaviour of Micro and Nano Scaled Silicon Carbide Reinforced Al 6063 Metal Matrix Composite

In this research study Al 6063 is used as the base matrix element, due to less weight, high specific strength, impact strength and good mechanical properties. Further, SiC are reinforced in Al 6063 matrix for enhancing its properties. Stir casting process has been accomplished for fabricating the (Al 6063-SiC) composites. In this experiment two various size of reinforcement particle are utilized, one of them is micro sized and another one is nano sized. Micro sized reinforcement particle has dimensions of (25-40µ), while nano sized particle consists dimensions of 500nm. The weight fraction of the micro and nano sized SiC particle taken in this experiment are in order of 0%, 2%, 4%, 6%, 8%, and 10% respectively. Various mechanical tests such as hardness, tensile tests and impact tests were conducted for determining the effect of micro and nano sized SiC reinforced aluminum matrix composites. The comparative study related with impact strength, hardness and tensile strength of micro and nano sized silicon carbide reinforced with aluminum matrix composites were shown in this work. There is an enhancement of mechanical properties has been observed with enhancement in weight percentage of micro sized silicon carbide, on other hand there is also a decrease in mechanical properties has been found while increasing the weight percentage of nano sized silicon carbide. The main objective of this paper is to enhance the mechanical properties of the Al 6063 metal matrix with reinforcing silicon carbide particle.

Experimental study on tool wear in ultrasonic vibration–assisted milling of C/SiC composites

Carbon-fiber reinforced silicon carbide matrix (C/SiC) composites are typical difficult-to-cut materials due to high hardness and brittleness. Aiming at the problem of the serious tool wear in conventional milling (CM) C/SiC composite process, ultrasonic vibration–assisted milling (UVAM) and conventional milling tests with a diamond-coated milling cutter were conducted. Theoretical and experimental research on the cutting force during the ultrasonic vibration milling process of C/SiC composites is carried out. Based on the kinematics analysis of tool path during ultrasonic vibration milling process, the cutting force model of ultrasonic vibration milling is established, and the influence mechanism of ultrasonic vibration on the cutting force is revealed. Based on the analysis of the evolution law of tool wear profile and wear curve during the traditional milling and ultrasonic vibration milling of C/SiC, the tool wear forms and mechanism of diamond-coated milling cutters in two processing modes and the influence mechanism of ultrasonic vibration on tool wear are revealed. It is found that the main wear mechanism of the diamond-coated milling cutter is abrasive wear, and the main wear form is the coating peeling. Compared with the traditional milling, the tool wear can be reduced by the ultrasonic vibration milling in machining process. In the range of test parameters, the tool wear decreases first and then increases with the increase of ultrasonic amplitude.

The effects of preparation temperature on the SiCf/SiC 3D4d woven composite

Continuous silicon carbide fiber reinforced silicon carbide matrix (SiCf/SiC) composites have promising applications in aero-engine due to their unique advantages, such as low density, high modulus and strength, outstanding high temperature resistance and oxidation resistance. As SiC fibers are main reinforcements in SiCf/SiC composites, the crystallization rate and initial damage degree of SiC fibers are seriously influenced by preparation temperatures of SiCf/SiC composites, namely mechanical properties of SiC fibers and SiCf/SiC composites are influenced by preparation temperatures. In this paper, KD-II SiC fibers were woven into 3D4d preforms and SiC matrix was fabricated by PIP process at 1100 °C, 1200 °C, 1400 °C and 1600 °C. Digital image correlation (DIC) method was adopted to measure the uniaxial tensile properties of these SiCf/SiC composites. In addition, finite element method (FEM) based on representative volume element (RVE) was adopted to predict the mechanical properties of SiCf/SiC composites. The good agreements between numerical results and experimental results of uniaxial tensile tests verified the validity of the RVE. In last, the transverse tensile, transverse shear, uniaxial shear properties were predicted by this method. The predicted results illustrated that axial tensile, transverse tensile and axial shear properties were greatly influenced by the preparation temperatures of SiCf/SiC composites while transverse shear properties were not significantly various. And the mechanical properties of SiCf/SiC composites peaked at 1200 °C among these four temperatures while their values reached their lowest points at 1600 °C because of thermal damage and brittle failure of SiCf/SiC composites.