LM13 Alloy Research Articles

Eksperiment i istraživanje tvrdoće i zatezne čvrstoće u mikrostrukturi hibridnih kompozita sa metalnom matricom od Al - Gr - Fe3O4

In the current scenario, aluminium metal matrix composites (AMMCs) are most important as an auspicious high class of materials. Metal matrix composites are emerging as very much endowed materials exclusively in the fields of automotive, aerospace, electrical and electronics for their numerous applications and technical challenging properties. In the present work, a courageous is perfect to prepare and compare the hardness and tensile properties of LM25-graphite (Gr) and LM25-graphite (Gr)-Ferrous oxide (Fe3O4) hybrid composites. The composites were primed to make use of stir casting process in which quantity of reinforcement is speckled from 4 wt% of Gr and 3 wt% of Fe3O4. The prepared composites are characterized by micro-structural studies and tensile properties were estimated as per the standards. The microphotographs of the composites revealed the reasonably homogeneous supply of the particles in composites with a group at a small number of places. The dispersed graphite and Fe3O4 in LM25 alloy contributed to enhancing the tensile strength of the composites. The SEM of the illustration specifies the homogeneous supply of the reinforcement particles in the matrix without any annulled.

Synthesis and characterization of Al-B4C nano composites

Abstract In the present study, effect of incorporation of varying weight percentages (0.5, 1, 1.5, and 2) of boron carbide nanoparticles in aluminum-silicon alloy LM6 is investigated. Nanocomposites are fabricated using ultrasonic vibration assisted stir casting process. Field emission scanning electron microscopy (FESEM) and Energy Dispersive spectroscopy images are used to characterize the base alloy and fabricated composites. Nanoparticles are seen to be homogeneously incorporated in the alloy matrix. Refinement in the microstructure is seen effecting improvement in the hardness and density of composites. Hardness values of as cast composites are obtained using Vickers microhardness tester which are found to be higher than the base alloy.

Heat treatment and mechanical characterization of LM-25/tungsten carbide metal matrix composites

Abstract In this work, the effect of heat treatment on the mechanical properties and the microstructure of heat treated aluminium alloy LM 25 (Al-Si7-Mg) as well as on the metal matrix composite (LM 25), reinforced with tungsten carbide (WC) has been experimentally studied. The composites were fabricated through Stir Casting Method with LM 25 as matrix material and tungsten carbide (WC) with 0%, 3%, 6% and 9% by weight as reinforcement material. The specimens were made as per ASTM standards in order to test for its tensile strength, hardness and wear performance. It is observed that LM 25 alloy aged at 150 °C has better mechanical properties. Significant improvement in tensile strength and hardness is observed with addition of WC as reinforcement. The results show up to 30% improvement in wear strength of 6% and 9%wt WC when compared to 0%wt WC. The property enhancement of the composites can be achieved by adding WC in to LM 25.

Effect of Heat Treatment on Tensile and Corrosion Properties of LM6 Hybrid Metal Matrix Composite Reinforced with Cenosphere and Red Mud

The increased expectation of automotive, aviation and marine industries pertaining to the enhanced properties and their use in elevated temperature conditions and also corrosive environments leads to the development of the newer material to meet the requirements. The requirements of the automobile and marine applications call for the increased mechanical properties and lower density accompanied with higher resistance to oxidation. Hence the present research work is aimed at the development of Hybrid metal matrix composites (HMMCs) using low-density base material and reinforcements. The aluminum of grade LM6 is preferred material in automobile industries, because it can be cast to any complex geometry and possess good machinability, further upon heat treatment, the properties of LM6 alloy can be enhanced to meet the industry requirements. However, requirements of automobile industries consist of increased mechanical properties, lower density and higher corrosion resistance. Hence, in the present research work, it is aimed to develop newer composite material using LM 6 grade Aluminum alloy as matrix material which is reinforced with varied percent Cenosphere and Red mud.

Effect of mould vibration on the mechanical properties of aluminium alloy castings

This paper presents the effects of mould vibration on the mechanical properties and microstructure of LM6 and LM26 aluminum alloy castings at different vibration frequencies. The vibration frequencies used during the solidification process were 0, 5 and 9 Hz. The mechanical tests conducted were hardness test, tensile test and fatigue test while microstructure analysis was performed using scanning electron microscope. The experimental results show that the mechanical properties of LM6 and LM26 alloys can be improved by vibration. It was observed that increase in vibration frequency up to 9 Hz led to an increase in ultimate tensile strength from 89.11 to 100.17 MPa for LM6 and from 102.42 to 117.65 MPa for LM26 aluminum alloys. It was also found that hardness and fatigue life improved significantly with the increase in vibration frequency. The microstructural studies reveal finer grains, fragmented microstructure, better distribution and low porosity with the increased application of vibration. This leads to less defects and improved mechanical properties in castings products.

Analysis of Filling in Thin Section by FEM Based Simulation for LM6 Material

This paper deals with the cooling characteristics of LM6 alloy used as a pouring material for manufacturing of thin hollow rectangular section during the solidification process inside the mold. For purpose of an accurate mathematical modeling, it is essential to establish appropriate gating design and pouring temperature. Here simulation experimental study is carried out by using Pro CAST 2009.0 for LM6 alloy. In this investigation pouring is done on thin rectangular section at different pouring temperature and sprue height. Finally a comprehensive analysis result shows that for efficient casting, pouring temperature is more significant parameter as compared to sprue height.

Synthesis and Dry Sliding behaviour of LM24-TiB₂ Reinforced Particulate Composite

The existing effort deals with synthesis of (LM24) composite developed by reinforcing 3wt % and 5wt % TiB2 particles in the size range of 20-60 μm in the LM24 matrix. Hardness of the alloy and the composites were evaluated to see the changes in the hardness of the materials. The sliding wear tests were performed using pin on disc machine to study the wear properties. Effect of various experimental parameters like sliding distance, and applied pressure were studied on sliding wear response of the alloy and the composite. Micro structural examination of the alloy and composite was done to see the structural changes and distribution of the particles in the matrix. Worn surfaces were examined to see the mechanism of material removal. Results show that reinforcement of TiB2 particles in LM24 alloy increases the hardness and wear resistance. Microstructural study of the base alloy LM24 and composites were performed having special attention to the dispersion of TiB2 particles in LM24 base alloy matrix and interface closeness between TiB2 particles and LM24 alloy matrix. The microstructure of aluminium alloy shows primary Al dendrites and intermetallic phases around in the inter-dendrites region. The TiB2 particles were noted to be more or less uniformly distributed within the metallic matrix and these particles were trapped within the primary aluminium dendrites instead of inter-dendritic region.The importance of this work is to study the importance of TiB2 particles in enhancing the properties of the base alloy. In general, the properties of unreinforced materials show poor mechanical as well as wear properties and there is a need to improve the properties to a certain level so that the material can be extended to a certain level for its usefulness. In the present work, it has been observed that after reinforcing TiB2 particles to the base alloy considerable amount of enhancement in the properties can be achieved. It is quite sure that this project work will certainly help in designing of the various parts.

Synthesis & Analysis Of Mechanical Properties Of LM24/B4C Particulate Composites

Aluminium Matrix Composites (AMCs) are nowadays under serious consideration to replace conventional materials for a large number of structural applications such as those in the aeronautical/aerospace, transportation, defense and sports industries because of their superior properties. The excellent mechanical properties and comparatively low cost make them as an attractive option. They were developed to meet the demands for lighter materials with high specific strength, stiffness and wear resistance. Particulate reinforcement is among one of the routes to improve the strength, ductility and toughness of the composites. Their ability to be produced by conventional method such as stir casting and powder metallurgy is an added advantage. A lot of researchers have tried to synthesize these materials using numerous combinations. The present investigation deals with synthesis and mechanical properties evaluation of LM24 alloy based composites reinforced with B4C particles in order to find its feasibility for application in flywheels of sports vehicles, connecting rods etc. Thus properties such as density, ultimate tensile strength, hardness, Impact strength were found at different compositions and after proper analysis various results were generated.

An investigation on the tensile properties and micro-structure of hybrid metal matrix composites

In recent years, aluminium metal matrix composites (AMMCs) have emerged as a promising high class of materials. Metal matrix composites are emerging as very promising materials especially in the fields of aerospace, electrical, electronics and automotive for their various applications and technical demanding properties. In the present work, a brave is consummate to prepare and compare the tensile properties of LM25-Gr and LM25-graphite/boron carbide (B4C) hybrid composites. The composites were primed to make use of stir casting process in which quantity of reinforcement is speckled from 4 wt% of Gr and 3 wt% of B4C. The prepared composites are characterised by micro-structural studies and tensile properties were estimated as per the standards. The microphotographs of the composites revealed the reasonably homogeneous supply of the particles in composites with a group at a small number of places. The dispersed graphite and B4C in LM25 alloy contributed in enhancing the tensile strength of the composites. The SEM of the illustration specifies the homogeneous supply of the reinforcement particles in the matrix without any annulled.

Optimization of Machining Parameters for CNC Turning of Al/Al2O3 MMC Using RSM Approach

This paper discusses the influence of cutting variables such as feed, cutting speed and depth of cut at work-tool interface zone temperature and surface finish while machining aluminium alloy LM6 reinforced with Al2O3 metal matrix composites. Response surface methodology with central composite rotatable design matrix was employed to optimise and analyse the cutting variables. Second order regression models were developed for predicting the output responses and the adequacy of the developed model was tested using analysis of variance (ANOVA). ANOVA results revealed that the feed and depth of cut were the major influencing parameters for the work-tool interface temperature and cutting speed and feed were prominent influential parameters in surface roughness. The optimal parameters for multiple responses were arrived for the specified range of input parameters using overall desirability index.

Influence of Process Parameters on CNC Turning of Aluminium Hybrid Metal Matrix Composites

An effort has been made in this investigation to find the influence of turning process parameters on the machinability of hybrid metal matrix composite comprising alumina (Al2O3) and molybdenum disulphide (MoS2) particulates dispersed on aluminium casting alloy LM6 in turning process. Design of Experiments approach was used to plan the experiments and the acquired data were analysed using design expert software associated with response surface method (RSM). In this paper work cutting speed, feed and depth of cut were considered as input process parameters and the resultant force of cutting forces in three directions, Specific Cutting Pressure (SCP) and surface roughness Ra were considered as responses. Statistical analyses were carried out to estimate the performance of machining parameters. The influence of input parameters on machining-force, SCP and the surface roughness Ra were analysed using surface response graphs. The experimental study revealed that cutting speed and feed were the most influencing parameter that affects the machining force and SCP.

Ann Based Optimization Model for Die Casting of Aluminium Alloy Lm6

Ann Based Optimization Model for Die Casting of Aluminium Alloy Lm6

Wear Characteristics of LM13 Alloy with Course Size of Rutile Reinforcement

Wear Characteristics of LM13 Alloy with Course Size of Rutile Reinforcement

Micro structural and static structural analysis of LM6/B4C and LM6/B4C/GR hybrid aluminium metal matrix composites

This research work was performed to interpret the fabrication and mechanical characteristics of LM6/B4C and LM6/B4C/Gr aluminium matrix composites. The aluminium matrix composites were manufactured by reinforcing B4C particles with varying wt % of 3, 5, 7 using stir casting technique. LM6/B4C 7% composite was made hybrid by adding 2% Graphite into it. The presence of graphite in such composites provide the self-lubricating effect, replacing conventional sliding contacts (bearings, sheaves, pistons, pulleys) with them. This also helps to reduce the lubricating oil and fuel consumption along with environmental benefits reducing energy wastage in industrial and automotive components. The properties of the composites were collated with the base alloy to analyse the enhancement in mechanical characteristics that had been transmitted by the reinforcement particles to the composites. The specimen microstructure was inspected using an optical microscope to ensure the uniform distribution of reinforcement particles in the matrix. The piston was modelled in CREO and using ANSYS 14.5 workbench static structural analysis of LM6 alloy, LM6/B4C composite and LM6/B4C/Gr hybrid aluminium composites are executed. Compared to LM6 alloy, better static structural properties were obtained in composites and hybrid composite.

Weldability Study of LM25/ZrO2 Composites by Using Friction Welding

In this paper aluminum (LM25) alloy was chosen as a base matrix metal, and it was reinforced with 0, 3, 6, 9, 12% of Zirconium dioxide (ZrO2) particulates based on weight fraction method. Stir casting method was used to cast LM25/ZrO2 composite material. The cast samples were subjected to physical and mechanical test viz, density, hardness, tensile, compression and impact test. The feasibility trial weld was carried out on the developed composite (similar metals) using Friction welding process (FSW) and then welded sample were prepared for the various test. The welded samples were subjected to various mechanical tests such as tensile, hardness and bend test to evaluate the strength of the friction welded joints. Then welded samples were also subjected to optical microscopy analysis to evaluate microstructures of the base and the weld regions. The tensile, hardness, compression and impact strength increases with increase in the percentage of ZrO2 in LM25 alloy. The tensile, hardness and bending strength were high in the welded zone. The microstructures of the welded tensile tested specimen were analyzed using the Scanning Electron Microscopy (SEM) in a different region of the welded area. From the above results shows weldability of LM25/ZrO2 composites was improved with the increase in weight percentage of ZrO2 reinforcement.

Optimization of friction and wear behaviour of Al–Si3N4 nano composite and Al–Gr–Si3N4 hybrid composite under dry sliding conditions

The tribological behaviour of gravity die stir cast LM6 alloy with graphite (Gr) and silicon nitride nanoparticles was investigated. Al–Gr–Si3N4 hybrid composite, Al–Si3N4 nanocomposite and Al–Gr nanocomposites were separately fabricated to investigate their frictional and wear characteristics under dry sliding conditions. EDS was used to ensure the uniform presence of nano Si3N4 and graphite in the cast. L9 orthogonal array method was chosen to conduct the experiments to study the effect of different applied loads (20, 30 and 40 N) and sliding distances (1, 2 and 3 km). The results showed that the respective wear rate and coefficient of friction (COF) decreased by 25% and 15% for hybrid composite when compared with those of Al–Si3N4 nanocomposite whereas the wear rate and COF of Al–Gr was found to be very minimal. The micro Vickers hardness of the hybrid composite was 14% more than that of the simple nanocomposite and there was not much notable variation for Al–Gr and Al–Si3N4 nanocomposite materials. Scanning electron microscope was used to analyze the worn surface and subsurface, from which it was noted that the predominant wear mechanisms observed were abrasive for nanocomposite and both abrasive and adhesive mechanism for hybrid composite. Analysis of variance (ANOVA) and F-test were used to check the validity model and to determine the significant parameters affecting the wear rates.

Microstructural and Erosive Wear Behavior on Coarse Silica Sand of Dual Reinforced Particle (DRP) LM-13 Alloy Composites

The present investigations are a comparative study and effects of SiC and ZrSiO4 ceramic grain sizes and mixing proportions on the microstructural and slurry erosion wear characteristics of composite materials. SiC / ZrSiO4 dual reinforced particles (DRP) LM-13 alloy matrix composites were manufactured. Dual reinforced particles composites were generated by adding combinations of (9+3)wt%,(6+6)wt%, (3+9)wt% of Silicon carbide (SiC) and zircon sand (ZrSiO4) to LM-13 alloy matrix composites. LM-13 alloy composite with Silicon carbide and zircon sand samples were also prepared for comparison of dual reinforcement particles on microstructural features and wear behavior in various slurry concentrations. Silicon carbide (35-44 µm) and zircon sand (20-35 µm) particles are reinforced in the alloy by two-step stir casting method. Slurry erosion wear study reveals that the dual particle reinforcement enhances the wear resistance as compared to single particle reinforcement if mixed in a definite proportion. Study also indicate that a combination of 12% reinforcement of silicon carbide and zircon sand particles in the ratio of 9 and 3wt% into the composite exhibits better microhardness and wear resistance as compared to other combination.

Investigation of mechanical properties and electrical discharge machining of LM25-RHA metal matrix composite

In this work, the effect of weight percentage of rice husk ash (RHA) on mechanical properties and machinability of LM25 alloy of aluminium has been investigated. RHA has been mixed with the LM25 alloy by 4%, 6%, 8%, and 12% and aluminium metal composite (AMC) has been prepared by two-step stir casting process. The tensile strength, compressive strength, wear strength, hardness and optical microscopy examination have been done in order to characterise the AMC. Composite prepared. Further, the machinability has been investigated by conducting experiments on electrical discharge machining (EDM). The experiments have been conducted on Taguchi's L9 orthogonal array, the parameters being weight percentage (wt%), pulse current (Ip), pulse on time (Ton), and gap voltage (V) and the responses are material removal rate (MRR), tool wear rate (TWR), and surface roughness (Ra). The result reveals that the tensile, compressive, wear strength and hardness has increased sharply by increasing the reinforcing RHA. Further, Ip is significant parameter for MRR which shows an increasing trend with the pulse current, similar observation has seen with TWR, while Ra has increased by varying percentages of RHA from 4% to 12%. The microstructure examination through an optical microscope shows the uniform distribution of RHA into the base alloy with some casting defects.

Investigation of mechanical properties and electrical discharge machining of LM25-RHA metal matrix composite

In this work, the effect of weight percentage of rice husk ash (RHA) on mechanical properties and machinability of LM25 alloy of aluminium has been investigated. RHA has been mixed with the LM25 alloy by 4%, 6%, 8%, and 12% and aluminium metal composite (AMC) has been prepared by two-step stir casting process. The tensile strength, compressive strength, wear strength, hardness and optical microscopy examination have been done in order to characterise the AMC. Composite prepared. Further, the machinability has been investigated by conducting experiments on electrical discharge machining (EDM). The experiments have been conducted on Taguchi's L9 orthogonal array, the parameters being weight percentage (wt%), pulse current (Ip), pulse on time (Ton), and gap voltage (V) and the responses are material removal rate (MRR), tool wear rate (TWR), and surface roughness (Ra). The result reveals that the tensile, compressive, wear strength and hardness has increased sharply by increasing the reinforcing RHA. Further, Ip is significant parameter for MRR which shows an increasing trend with the pulse current, similar observation has seen with TWR, while Ra has increased by varying percentages of RHA from 4% to 12%. The microstructure examination through an optical microscope shows the uniform distribution of RHA into the base alloy with some casting defects.

Effects of Iron, Manganese, and Cooling Rate on Microstructure and Dry Sliding Wear Behavior of LM13 Aluminum Alloy

ABSTRACTThe presence of Fe in eutectic Al-Si alloy can give rise to formation of a β-Al5FeSi needle-like phase because of low solubility of Fe in this alloy. The brittle nature of this phase leads to decreased mechanical properties of piston alloys, one of which is wear resistance. In this research, to modify β-Fe morphology, Sr and Mn elements were added to the samples prepared from LM13 containing different amounts of Fe. The effect of cooling rate on wear properties of this alloy was also investigated. Results show that the addition of Mn/Fe at aratio of 1/2 can modify the needle-like intermetallics present in the samples containing up to 1.2 wt% Fe. In addition, increasing the cooling rate from 3 to 15°C s−1 refined the eutectic structure and the intermetallics. Hence, it can be considered as another important factor to improve the wear properties of LM13 alloy. To study the wear behavior of this alloy, worn surface and subsurface areas were examined using scanning electron microscopy (SEM) equipped with an energy-dispersive spectrometry (EDS) analyzer.