Influence Of SiC Particles Research Articles

Influence of SiC particles on the microstructure and mechanical behaviors of AlMgScZr alloy processed by laser powder bed fusion

Laser powder bed fusion (LPBF) of AlMgScZr alloy has garnered significant attention as a high-strength aluminum alloy. However, its low modulus, Portevin-Le Chatelier (PLC) behavior, and weak strain hardening capability restrict its application in the aerospace sector. In this study, SiC/AlMgScZr composites with different SiC content have been successfully fabricated using LPBF. The inherent bimodal grain structure of AlMgScZr alloy was not completely altered by the addition of SiC particles. However, with increasing SiC content, heat accumulation increased, and the solidification cooling rate decreased. This led to an increase in the size of α-Al grains in the 5 wt% SiC/AlMgScZr composites. Meanwhile, movable dislocations can be efficiently preserved inside the grains, where they effectively accumulate and become entangled. Consequently, the strain hardening capability of the 5 wt% SiC/AlMgScZr composites improved by approximately 58 % compared to AlMgScZr alloy, with a strain hardening index (n) reaching 0.29. Additionally, the addition of SiC particles led to an increase in the elastic modulus (81.0 GPa). Furthermore, the reaction between Mg atoms and SiC particles resulted in the formation of Mg2Si, which altered the distribution of Mg elements and initiated the reactive precipitation of a Mg-rich phase. There is no competition between the diffusive migration of solute atoms and the motion of movable dislocations within the composites. The additional SiC particles effectively eliminated the PLC effect in the LPBF of AlMgScZr alloy. This work provides essential guidance for developing high-strength and high-stiffness aluminum matrix composites with excellent processing properties in LPBF technology.

Development of Novel Wear Equation of AA7050/SiC-Steel Interface for High Temperature Application

AA7050 aluminium alloy used for the main landing gear link was reinforced with SiC particles utilizing stir casting and uniform dispersion of reinforced particles was analyzed through SEM with EDS mapping. Wear test were performed on pin on disc apparatus by varying the process parameters and experimental runs were designed using response surface methodology. The influence of SiC particles on wear resistance at high temperatures was explored and the findings led to the development of a novel wear equation. The hardness of composites increased due to impediments of dislocation movement, and it declines with an increase in temperature owing to a reduction of Pierls stresses. The formation of a Mechanically Mixed Layer (MML) enhances wear resistance with the inclusion of reinforced particles, and the breakdown of this layer swifts the wear from moderate to severe. The mode of wear was a combination of shearing and abrasive at room temperature, shearing and adhesive until the temperature 200ᵒC, and plastic deformation when the temperature exceeded 200 °C, which was confirmed by worn surface morphology.

Influence of SiC particles and post-heat treatment on the properties of Ti-6Al-4V-based surface nanocomposite fabricated by friction stir processing

Friction stir processing was used to successfully fabricate a Ti-6Al-4V-based surface nanocomposite with a uniform dispersion of SiC reinforcement particles (FSP). Reinforced SiC particles showed good interfacial bonding with the matrix material. Microstructural modification after FSP and post-FSP heat treatment in terms of grain refinement and reinforcement behavior of SiC particles was investigated using an optical microscope (OM), scanning electron microscope (SEM), and electron back-scattered diffraction (EBSD). Microhardness test, Charpy impact test, and pin-on-disc wear test were carried out to measure the hardness, impact toughness, and tribological behavior of fabricated surface composites, respectively. Fully β-transformed microstructure comprising a mixture of fine basket-weave lamellar α/β and ultrafine martensite α′ was evident in the FSPed stir zone. The incorporation of SiC reinforcement resulted in additional microstructure refinement during FSP due to Zener pinning and particle-stimulated nucleation (PSN) caused by SiC particles. Nearly two-fold improvements in microhardness and wear resistance, whereas a slight but noteworthy improvement in impact toughness was observed. Enhancements in mechanical and wear properties were primarily ascribed to the combined effect of microstructural refinement, formation of martensite (α′), and dispersion strengthening (Orowan Mechanism).

Modeling and investigation of cutting force for SiCp/Al composites during ultrasonic vibration-assisted turning

The machining process of SiCp/Al composites is considerably difficult because of the addition of ceramic particles. As an effective machining method, ultrasonic vibration-assisted turning is used to process SiCp/Al composites, which can effectively reduce the cutting force, improve the surface quality, and reduce the tool wear. This study developed a cutting force prediction model for ultrasonic vibration-assisted turning of SiCp/Al composites, which comprehensively considers the instantaneous depth of cut and the instantaneous shear angle. This model divides the cutting force into the chip formation force considering the instantaneous depth of cut, the friction force considering the influence of SiC particles at tool-chip interface, the particle fracture force, and the ultrasonic impact force in the cutting depth direction. By comparing the predicted value of the main cutting force with the experimental values, the results present the same trend, which verifies the feasibility of the cutting force prediction model. In addition, the influence of vibration amplitude, depth of cut, and cutting speed on the main cutting force is analyzed. The systematic cutting experiments show that ultrasonic vibration-assisted turning can significantly reduce the cutting force and improve the machinability of SiCp/Al composites.

Influence of SiC Particles on Mechanical and Microstructural Properties of Modified Interlock Friction Stir Weld Lap Joint for Automotive Grade Aluminium Alloy

The present requirement of the aerospace industry is seeking light-weight joining material that satisfies the technical and technological requirements with better mechanical characteristics. Aluminum alloy with spot-welding process meet the requirements of modern demands. In this present paper, a modified-interlock friction stir weld lap joint is induced to join AA8011-AA7475 with different wt% of SiC particles. Friction stir machine process parameters were tool rotational speed 1600 rpm, plunge speed rate 0.08 mm/s and traverse speed 40 mm/s maintained constantly. Mechanical and metallurgical characterizations were investigated. EDS analysis and microstructure confirmed the presence of silica particles in the NZ of the weld joints and uniformed homogenous distribution of the particulates throughout the weld. Joints made with SiC particulates showed improved static properties because intensive softening occurred in the stir zone leading to Si-Al-based precipitate particulates. The fracture test showed that the joints with SiC had a ductile fracture. AA8011-AA7475 with 2 wt% SiC showed maximum hardness, tensile strength of 229 HV, 192 MPa and a decrease in elongation was observed from 9.5 to 5%. AA8011-AA7475/2 wt% showed improved hardness, tensile strength and elongation suitable for aircraft wing stringers application.

Influence of reinforcement particles on the mechanism of the blasting erosion arc machining of SiC/Al composites

Electrical arc machining has shown its remarkable efficiency in processing difficult-to-cut materials, especially high-temperature alloys and metal-based composites. Despite several studies about the material removal mechanisms of the electrical arc machining of metal alloys, few of these reports relate to the mechanism of machining composites with electrical arcing. Considering that reinforcements such as SiC particles have different thermal and electrical properties with metal alloys, research on the influence of SiC reinforcement on the electrical arc machining process is important and necessary. Based on comparison experiments using 20 and 50 vol.% SiC/Al composites, this research focused on the influence of SiC particles on the machining performance and material removal mechanism of blasting erosion arc machining (BEAM), and further analyzed the influence of reinforcements on composite material removal mechanisms. Analysis revealed that the molten material expelling mechanism is also influenced by the SiC fraction difference. For the BEAM of lower SiC fraction composites, both the SiC particles and the molten aluminum are mainly pumped and ejected by the flushing dielectric. In greater SiC fraction composites, most SiC particles are directly sublimed by heat. In addition, the mechanism of BEAM in the material removal and tool wear of SiC/Al composites was discussed based on heat transfer simulation and observation. Furthermore, the results disclosed that many chemical reactions take place during machining that have an obvious influence on the tool wear rate.

Microstructural and sliding wear behavior of SiC-particle reinforced copper matrix composites fabricated by sintering and sinter-forging processes

Cu and Cu/SiCp composite compacts were prepared through sintering and sinter-forging processes. Influence of SiC particles and fabrication type on the tribological behavior of pure Cu and Cu/SiCp composites was investigated. Dry sliding wear tests represented that the sinter-forged Cu composite compacts with 60vol.% SiC exhibit the lowest wear loss compared to other compacts. Moreover, the results indicated that applying compressive force during sintering process of Cu and Cu/SiCp compacts has a significant effect on reducing and eliminating porosities and achieving to higher bulk density. Therefore, wear loss of the Cu and Cu/SiCp compacts produced through sinter-forging process was improved significantly compared to conventionally sintered Cu and Cu/SiCp composite compacts.

Influence of SiC particles on compressive deformation of magnesium matrix composites

Abstract The influence of the presence of ceramic particles on the twinning mechanism in magnesium matrix composites was measured using synchrotron radiation diffraction during in situ compressive tests. As with the unreinforced alloys, the plasticity of extruded composites is controlled by the 〈 1 0 1 ¯ 1 ¯ 〉 { 1 0 1 ¯ 2 } tensile twining process. However, the volume fraction of twins is rapidly saturated as the volume fraction of reinforcement increases. SiC particles balance the tensile stress generated by twins during plastic deformation.

An investigation of the effect of work piece reinforcing percentage on the machinability of Al-SiC metal matrix composites

This paper presents the study of the tool wear mechanism in machining the metal matrix composites (MMC) and its dependence on the percentage of reinforcing with MMC. Aluminum alloy (A356 - SiC) silicon carbide metal matrix composite of two samples, were prepared in-house by using stir casting method. Samples having 10 and 20% silicon carbide particles (grain size ranging from 55 to 85 mm) by weight are fabricated in the form of cylindrical bars. Experiments were conducted in the medium duty lathe by using polycrystalline diamond (PCD) insert. Optimum parameters were obtained by analyzing the power consumed on an average surface roughness (Ra) of the machined component. By setting these optimum parameters at a constant machining condition, tool wear study was carried out for a time duration of 100 min. The result showed that the tool flank wears was maximum while machining 20% of the SiC reinforcing MMC when compared with 10% of the SiC reinforcing MMC. The result proved that the influence of SiC particles’ weight percentage was a dependent parameter on tool wear. The main mechanism of tool wear in machining Al-SiC MMC includes two-body abrasion and three-body abrasion. However, the tool wear images were captured by optical microscope and SEM, which supported the result. Key words: Machining, PCD, Al-SiC-MMC, different percentage of SiC reinforcing, power consumed, tool wear.

The Influence of SiC Particles on Tool Wear in Machining of Al/SiC Metal Matrix Composites Produced by Powder Extrusion

Metal matrix composites (MMCs) have received considerable attention due to their excellent engineering properties. However, poor machinability has been the main deterrent to their substitution for metal parts. The hardness and abrasive nature of reinforcement phase causes rapid tool wear during machining which results in high machining costs. In this study, the effect of SiC particles (5, 15 & 20 percent) on tool wear in turning process is experimentally investigated. Continuous dry turning of Al/SiC particulate metal matrix composite produced by powder metallurgy and utilizing titanium carbide inserts has been achieved as the test method. The influence of machining parameters, e.g. cutting speed, feed rate and depth of cut on tool wear and cutting forces were investigated during the experiments. The results show that tool wear increases with increasing cutting speed, depth of cut and feed rate. The cutting speed and depth of cut are more dominant factors compared to feed rate on the tool wear. In addition, it is concluded that the flank wear increases with the increase of SiC percentage in the MMC.

The influence of SiC particles on the corrosion resistance of electroless, Cu–P composite coating in 1 M HCl

The present paper aims to compare the corrosion resistance of the electroless Cu–P–SiC with Cu–P composite coating on carbon steel in 1 M HCl solution by the weight loss, potentiodynamic polarisation and electrochemical impedance spectroscopic (EIS) techniques. The study reveals that, the corrosion current density ( I corr) and the double layer capacitance ( C dl) values decrease, the charge transfer resistance ( R ct) and inhibition of efficiencies (IE %) increase with the incorporation of SiC particles in the Cu–P matrix indicating the improvement in corrosion resistance.

The Correlation between Plastic Deformation and Surface Properties of SiC Structured AM50 Magnesium Alloy

This research has focused on understanding the correlation between the raw material, processes, microstructure and corrosion behavior of AM50 containing SiC particles magnesium sheet. The magnesium sheets were produced from cast ingot AM50 containing different amount of SiC particles. The magnesium sheets were exposed to 3.5 % NaCl solution with Mg(OH)2 , pH=10.5 in room temperature. The influence of SiC particles on the micro-galvanic corrosion was studies by Scanning Kelvin Probe Force Microscopy.

The influence of SiC particles on the compressive properties of metal matrix composites

Room temperature compressive tests have been carried out on three metal matrix composites (MMCs), all based on the Al alloy CW67 and on monolithic material. The composites, CW67 alloy reinforced with homogeneously distributed SiC particles in three nominal sizes 0.7, 15 and 33 μm, were produced by hot pressing up to the theoretical density. The addition of the SiC particles increased the yield strength and elastic modulus while decreasing the ultimate compressive strength and ductility of the CW67 alloy in both the peak-aged and under-aged conditions. The greatest strengthening effects were achieved with the CW67–15 μm SiC composite material. Both the presence of agglomerations of small (0.7 μm) SiC particles and the cracking of large (33 μm) SiC particles had detrimental effects on CW67 alloy strengthening. The higher compressive strength and lower ductility were achieved with the peak-aged matrix compared with the under-aged matrix. The presence of SiC particles causes the aging process to be accelerated due to an increase in dislocation density, which provides more sites for the nucleation of precipitates.

201 Al基MMCのトライボロジー特性に及ぼすメゾ構造因子の影響について

The influence of SiC particles on the wear property of MMC based on AC4CH was studied in air at room temperature. Especially, the wear mechanism was investigated from viewpoint of mesoscopic size. The result indicated that the wear amount of MMC was less than that of AC4CH. SiC particles reduced wear amount of MMC. Therefor, the wear process of MMC was dominated by interaction between SiC particles and substrate.

Influence of SiC particles on mechanical properties of Mg based composite

AZ91 magnesium alloy reinforced with different sizes of SiC particulates has been fabricated using powder metallurgy route. Mechanical properties of the specimens have been studied. Yield and ultimate tensile stresses show a decrease with the increase in the size of SiC particulates. The influence of thermal shock between 400°C and 30°C on the mechanical properties was also investigated. The results show a decrease in yield stress and elongation to fracture with the number of thermal shock cycles.

Effect of SiC particles on fatigue crack propagation in SiC/Al composites

Fatigue crack propagation has been studied in two SiC particulate-reinforced aluminium-matrix composites with differing matrix alloys and composite heat treatments. Results indicate that the fatigue crack propagation rate (FCPR) of aged SiC/LY12 Al composites decreases with increasing volume fraction ( V f) of SiC particles; for composites containing 15 volume % SiC particles in an LY12 Al matrix the FCPR is independent of heat treatment (ageing or annealing). Annealed SiC/5083 Al composite has a higher FCPR than annealed SiC/LY12 AI. The influence of SiC particles on crack path is briefly discussed.

The effect of particulate SiC on fatigue crack growth in a cast-extruded aluminum alloy composite

Detailed micromechanical analyses of fatigue crack growth have been performed on a composite with 15 vol. pct particulate SiC in a peak-aged 2014 aluminum alloy matrix. This composite was manufactured by the Dural Aluminum Composites Company, San Diego, CA, by casting and extrusion. About 3 pct intermetallic particles were found in the matrix alloy in addition to those expected for this material. Fatigue cracks were grown from approximately threshold to rapid fracture. Analyses of the crack tips were performed by stereoimaging at low and intermediate stress intensities and just prior to the onset of rapid fracture. Detailed maps of strain were derived, and a considerable influence of SiC particles on strain was found. Analyses of microcracks near the main crack were made and found to have only a small influence on fracture. Fatigue threshold was explained on the basis of measured and calculated crack closure.