SiC Particle Reinforced Aluminium Alloy Research Articles

An overview of the effect of stirrer design on the mechanical properties of Aluminium Alloy Matrix Composites fabricated by stir casting

An overview of the effect of stirrer design on the mechanical properties of Aluminium Alloy Matrix Composites fabricated by stir casting

Electron beam surface heating-diffusion bonding: An effective joining method for aluminum alloy metal-matrix composite with high SiC volume

As a novel method to reduce the temperature during electron beam welding, and to subsequently inhibit interfacial reaction between SiC and Al matrix, the electron beam surface heating - diffusion bonding is proposed for joining SiC particle reinforced aluminum alloy metal - matrix composite of 45 vol.% SiC/2024 Al. The defocused electron beam was used to heat the base metal surface, and the simultaneous pressure was applied to the butt surface to achieve bonding. The base metals were successfully joined by diffusion. The maximum temperature of the whole joint was effectively decreased to less than 650 ℃. The Gibbs free energy change of interfacial reaction was calculated, meaning a positive value reaching 218 kJ/mol and a consequently prominent inhibitory effect on the formation of brittle Al4C3 that was proved by microstructural observation. The tensile strength for the bonded joint was increased by 35 % compared to that for ordinary welded joint. When the TC4 layer was added, TiC strengthening particles were formed with the deficiency of Al4C3, corresponding to the significantly increased tensile strength of 63 % of base metal (154 MPa).

Laser Shock Peening of SiCp/2009Al Composites: Microstructural Evolution, Residual Stress and Fatigue Behavior.

SiC particle reinforced aluminum alloy has a wide application in the aerospace industries. In this study, laser shock peening (LSP), an advanced surface modification technique, was employed for SiCp/2009Al composite to reveal its microstructure, microhardness and residual stress evolution. After peening, high densities of dislocations were induced in the aluminum substrate, and stacking faults were introduced into the SiC particle. The microhardness was increased from 155–170 HV to 170–185 HV, with an affected depth of more than 1.5 mm. Compressive residual stresses of more than 200 MPa were introduced. The three-point bending fatigue of the base material, laser peened and milled after laser peened specimens with artificial crack notch fabricated by a femtosecond laser was investigated. The average fatigue lives of laser peened and milled after laser peened specimens were increased by up to 10.60 and 2.66 times, compared with the base material. This combined fundamental and application-based research seeks to comprehensively explore the applicability of LSP on metal matrix composite.

Geometry segmentation of voxelized representations of heterogeneous microstructures using betweenness centrality

We present a robust method for automating removal of “segregation artifacts” in segmented tomographic images of three-dimensional heterogeneous microstructures. The objective of this method is to accurately identify and separate discrete features in composite materials where limitations in imaging resolution lead to spurious connections near close contacts. The method utilizes betweenness centrality, a measure of the importance of a node in the connectivity of a graph network, to identify voxels that create artificial bridges between otherwise distinct geometric features. To facilitate automation of the algorithm, we develop a relative centrality metric to allow for the selection of a threshold criterion that is not sensitive to inclusion size or shape. As a demonstration of the effectiveness of the algorithm, we report on the segmentation of a 3D reconstruction of a SiC particle reinforced aluminum alloy, imaged by X-ray synchrotron tomography.

Characterisation of thermal cycling induced cavitation in particle reinforced metal matrix composites by three-dimensional (3D) X-ray synchrotron tomography

Metal matrix composites are known for their high strength, fatigue resistance, and wear resistance. The coefficient of thermal expansion between the reinforcement and matrix can result in thermal stresses during thermal cycling. In this paper we quantify the evolution of cavitation damage in SiC particle reinforced aluminium alloy matrix composite subjected to thermal cycling by X-ray synchrotron tomography at the advanced photon source at the Argonne National Laboratory. It will be shown that, while surface examination did not show significant damage, X-ray synchrotron tomography enabled us to resolve and quantify the amount and nature of cavitation with increasing thermal cycling. The influence of the microstructure in damage initiation and evolution is discussed.

Mechanical Properties of Stirred SiC Reinforced Aluminium Alloy: Stir Casting with Different Composition of SiC, Blade Angle and Stirring Speed

Discontinuously reinforced cast metal-matrix composites are increasingly attracting the attention of aerospace, automotive and consumer goods industries. In this study, SiC particle reinforced aluminium alloy is selected to produce metal matrix composites (MMC) using different of parameters blade angle and stirring speed and composition of SiC reinforcement. Mechanical test, metallographic analysis and fracture analysis will be conducted to investigate mechanical properties of material and to observe particle distribution of SiC reinforcement and fracture properties respectively with varies angles and stirring speed of impellers and different composition of SiC reinforcement. Metallographic analysis on composition records at low speed, there exist a particle collection and gas existence on the specimen. At blade angles of 300, increasing on stirring speed and composition of SiC reinforcement may result better of particle distribution. For mechanical test, different composition of SiC reinforcement, blade angle and stirring speed will be affecting a mechanical property of material. The result of the experiment showed at blade angle 300, stirring speed 100rpm and 10% composition of SiC reinforcement give better result of hardness, ultimate strength, energy absorption, microstructure and fracture of composite. For this study, it proved that at the lower blade angle and the increment on stirring speed and composition of SiC reinforcement give a better result on particle distribution of SiC reinforcement, fracture and mechanical properties for A1-MMC.

Dissimilar aluminium weldability of SiC particle reinforced aluminium alloy to Al–Si, Al–Mg, Al–Mg–Si, Al–Zn–Mg–Cu alloys by electron beam welding

The SiC particle reinforced aluminum alloy has been developed for various machine parts. Aluminum welded machine parts often require welded joints composed of dissimilar alloys. In the present study, electron beam weldability of dissimilar joints was investigated on different combinations of aluminum alloys of 10 mm thickness. The main alloy is 10% SiC particle reinforced Al–Si aluminum alloy. Combination wrought alloys are Al–Si, Al–Mg, Al–Mg–Si and Al–Zn–Mg–Cu alloys. The electron beam machine is a 6 kW high voltage type. The joint groove is of square butt without filler metal. In the case of SiC reinforced alloy/Al–Si and Al–Mg, joints, weldability was poor because some weld imperfections were recognized such as arcing and other defects. In the case of SiC reinforced alloy/Al–Mg–Si, Al–Zn–Mg–Cu, the cracking sensitivity is low while some small porosity was recognized. Tensile strength became about 150 MPa such as SiC reinforced alloy. Impact values of the SiC reinforced alloy/Al–Mg–Si joint were recovered through 2160 h room temperature ageing. Micro segregation of the Si element was recognized for the SiC reinforced alloy/Al–Mg–Si joint by electron probe microanalyser analysis.

Multi-Scale Strength Evaluations of SiC Particle Reinforced Aluminum Alloy by Using FEM Superposition Method

This article presents a modified FEM Superpostion method (S-FEM) for composite material analysis. Around the reinforcement body, failure and interface fracture may occur in the matrix. So the S-FEM was employed to detect the stress distribution around the reinforcement. One particle in big matrix is studied. Area of twice of particle radium is selected as local field.First, the feasibility of modified S-FEM is verified. And by symmetric analysis, geometric distribution of particle which may influence on the strength of composite material were discussed.

Effect of microstructure on Young’s modulus of extruded Al–SiC composites studied by resonant ultrasound spectroscopy

In this work, an attempt was made to correlate the Young’s modulus of SiC particle reinforced aluminum alloy composites, measured by resonant ultrasound method, to reinforcement spatial distribution. Composites were fabricated by extrusion of billets that were previously formed using cold pressing blend of matrix alloy powders and ceramic particles. It has been shown that more aggregated microstructures were generated with an increase in ceramic volume fraction (to 20%) and the matrix alloy powder mean particle size from 40 to 180 μm as well as with a decrease in the reinforcement particle size (3–14 μm). At the same time, ultrasonic wave velocity as well as Young’s modulus diminish with a decrease in SiC content and its particle size, and with increase in matrix alloy particle size. The analysis showed that it could be partly attributed to the higher amount of residual porosity in agglomerated structures. An addition decrease of elastic characteristics was attributed to the increasing influence of mechanically imperfect contacts that formed between ceramic particles in the more aggregated microstructures.

Evaluation of material properties of SiC particle reinforced aluminum alloy composite using neutron and X-ray diffraction

The phase stresses under loading in a monolithic aluminum alloy and an aluminum alloy reinforced with silicon carbide particles were measured by the neutron diffraction method. Under uniaxial loading, the longitudinal and transverse strains in each constituent phase were measured. The diffraction elastic constants for each diffraction plane were investigated as a function of the diffraction intensity by TOF. Single peak analysis was carried out for each diffraction profile. The measured results were compared with the theoretical micromechanical models such as the self-consistent and Mori–Tanaka method using the Eshelby theory (MTE). The accuracy of the elastic constant strongly depends on the diffraction intensity. In order to confirm the rule of mixture, the phase stress was measured by the X-ray method. The macrostress calculated by the rule of mixture agreed very well with the applied stress. Finally, fatigue damage was evaluated by the neutron method. The change of the full width at half maximum in the aluminum phase during fatigue is small. On the other hand, the value in the SiC phase increased steeply just before fracture.

Influence of microstructure and experimental parameters on the erosion–corrosion behavior of Al alloy composites

The influence of material related parameters such as alloy composition and reinforcement volume fraction and the experimental parameters such as the slurry concentration and rotational speed on the erosion–corrosion behavior of SiC particle reinforced aluminum alloy composites in saline, acidic and basic environments is studied. It is observed that 2014–SiC composite exhibited better wear resistance than LM13–SiC composite in acidic and NaCl media. Further both the composites exhibited better wear resistance than their matrix alloys in these environments irrespective of the sand content in the slurry and the rotational speed. The wear rates increased with increasing sand content in both the media. Al/Si/precipitate interfaces were found to be the preferential sites for corrosive attack in both the alloys and composites. In basic media the trend was reversed with both the composites exhibiting lower wear resistance than their matrix alloys. Further 2014–SiC composite exhibited lower wear resistance than LM13–SiC composite in basic media.

Filaments in Superplastic Deformed SiC Particle Reinforced Aluminium Alloy Matrix Composites

Filaments in Superplastic Deformed SiC Particle Reinforced Aluminium Alloy Matrix Composites

Analyses of metallurgical behavior of Al–SiCp composites after ballistic impacts

The dynamic failure of SiC particle reinforced aluminum alloy composite; AA5083 is studied under ballistic impact loading. Tests were done with two different projectile types, AP (Army Piercing) 7.62 and 9 mm, and the hole surfaces created by the projectiles were investigated using both optical and scanning electron microscopy. Examination of the hole surface of the composite after dynamic failure showed microscopically ductile failure in the matrix following brittle cracking of the particles. The dynamic failure process involved both matrix and particle cracking. The high velocity of the projectile led to the melting of some surface layers because of the excess heat resulting from high velocity friction. Because of high friction, some melted regions had a porous structure due to shrinkage during rapid solidification caused by the high-speed projectile at the hole surface. The type of projectile strongly influenced the damage formation and the deformation type was also affected by the backing condition.

Preparation and some properties of SiC particle reinforced aluminium alloy composites

Abstract Aluminium alloy composites containing various particle sizes of 10 and 20 wt.% SiC particles were prepared by molten metal mixing and squeeze casting method under argon gas. The stirring was carried out with graphite impeller during addition of particle. The molten mixture was poured into a die when the stirring was completed and metal matrix composites were produced by applying the pressure. Optical microscopic examination, hardness, density and porosity measurement were carried out. Moreover, metal matrix composites were machined at various cutting speeds under a fixed depth of cut and feed rate using different cutting tools. It is observed that there was a reasonably uniform dispersion of particles in the matrix alloy. The density decreased with decreasing particle sizes, but porosity decreased considerably with increasing particle size. In addition, the tool life decreased considerably with increasing cutting speeds for all tests. Among cutting tools, the wear resistance of Al2O3 coated tools showed better performance than those of the other tools without chip breaker geometries in the machining of SiCp-reinforced composites.

Detection of particle damage event by acoustic emission during tensile straining of SiC particle reinforced aluminium alloy composites

The fracture mechanisms of composites which contain coarse second phase (30 µmSiC) have been studied by acoustic emissions measurement. The fracture mechanism for these composites is different from that for composites containing small particles. In the latter case, it is well known that the void nucleation during fracture occurs at interface between matrix and reinforcement. The experimental data and the current model for fracture were compared, and fracture strain has been estimated using a modified particle fracture model based on the Evensen void growth model. Acoustic emissions were detected from fractured particle, although there are some differences in AE responses caused by difference in heat treatment. Void nucleation occurs by particle fracture in all of the materials. A modified equation for the fracture strain has been proposed and this equation provides a good quantitative agreement with experimental data.

Application of a novel multilayer spray forming technology in the preparation of large dimension aluminium alloy blanks

Principle of multilayer spray forming and preparation technique of tubes and billets by it were presented and described in the article. The marked characteristic of multilayer spray forming technology is the to-and-fro movement of spray system, so the preform is deposited layer by layer with the surface of the deposit retaining relatively low temperature during the spray forming process. The two outstanding advantages of multilayer spray forming are as follows: suitable for manufacturing large dimension blanks, higher solidification cooling rate. Now Al-Fe-V-Si alloy (8009) and SiC particle reinforced aluminium alloy metal matrix composite billets of 300–600 mm in diameter and tubular blanks of size up to 650 mm in outer diameter, 360 mm in inner diameter and 1 200 mm in length have been made with the technology. After extrusion, the material has good properties.

New Retainer Material for High Speed and High Temperature Cylindrical Roller Bearing

Cylindrical roller bearings are being developed which can operate over 300°C and greater than three million DN for innovative gas-generators. Under such severe conditions, it is necessary for retainers to be frictionless, lightweight and strong. After preliminary testing, SiC particle reinforced aluminum alloy composite appeared to have good friction and wear properties. It's specific gravity is about one-third of the present material in use, silver-coated SAE4340. In the course of the study, two different friction and wear tests were conducted to investigate the optimum volume fraction of SiC. The results indicated that the most efficient volume fraction was 20vol%. The tensile strength of Al-20vol%SiC was about 140MPa at 300°C. Based on the results of FEM analysis, 140MPa is considered sufficient to endure any stress concentration caused by tensile hoop stresses up to four million DN. Presented at the 54th Annual Meeting Las Vegas, Nevada May 23–27, 1999

High pwder Nd-YAG laser welding of SiC particle reinforced aluminium alloy 2124

The effects of different Nd-YAG laser output waveforms on the weldability of a SiC particle reinforced aluminium alloy 2124 have been studied. The results show that although the square waveform can produce the greatest depth-of-penetration among the three different waveforms studied, i.e. continuous wave, sine wave and square wave, a high level of porosity was observed in the weld. Alternatively, porosity free welds with a reasonable depth-of-penetration can be obtained by using a sine waveform operated at high peak powers. However, the results also show that it would be difficult to stop theformation of aluminium carbides entirely in the fusion zone simply by varying the laser output parameters and the waveform. In order to stop the, formation of carbides, a new laser joining technique has been developed. This involved brush plating of nickel on the joining surfaces before laser welding. The results of the corrosion tests of the weld zone show that welding with a nickel coating would result in a much lower corrosion current than that without nickel coating.

High pwder Nd-YAG laser welding of SiC particle reinforced aluminium alloy 2124

High pwder Nd-YAG laser welding of SiC particle reinforced aluminium alloy 2124

Influence of thermomechanical processing on the tensile and fatigue properties of a SiC particle reinforced aluminium alloy: Harris, S.J., McColl, I.R. and Huang, Z.W. Proc. Conf. Developments and Applications of Ceramics and New Metal Alloys, Quebec City, Quebec, Canada, 29 Aug.-2 Sept. 1993, pp. 117–126

Influence of thermomechanical processing on the tensile and fatigue properties of a SiC particle reinforced aluminium alloy: Harris, S.J., McColl, I.R. and Huang, Z.W. Proc. Conf. Developments and Applications of Ceramics and New Metal Alloys, Quebec City, Quebec, Canada, 29 Aug.-2 Sept. 1993, pp. 117–126