Processing and Characterization of Functionally Graded In Situ Aluminum Composite

2015 ◽  
Vol 830-831 ◽  
pp. 485-488
Author(s):  
A.G. Arsha ◽  
E. Jayakumar ◽  
T.P.D. Rajan ◽  
Ballembettu Chandrasekhar Pai
Keyword(s):  
Centrifugal Casting ◽  
Wear Test ◽  
Primary Silicon ◽  
Functionally Graded ◽  
Die Design ◽  
Composition Analysis ◽  
Head Region ◽  
Aluminum Composite ◽  
Centrifugally Cast

A390 functionally graded material (FGM) pistons were fabricated by centrifugal casting, where the silicon particles were segregated in the head portion of the pistons by appropriate design and their density differences. Centrifugal casting offers casting of cylindrical structures with gradation in its properties. In centrifugally cast A390, a suitable die design can lead to the formation of hard primary Si particles gradually distributed towards the head region producing a particle rich zone, transition zone and matrix rich zone. Microstructure and chemical composition analysis confirms the composition gradation. Hardness and wear test results revealed that the gradation positively helps to improve the desired properties with the presence of in-situ primary silicon reinforcements.

Processing of Primary Silicon and Mg2Si Reinforced Hybrid Functionally Graded Aluminum Composites by Centrifugal Casting

2012 ◽  
Vol 710 ◽  
pp. 395-400 ◽  
Author(s):  
S. Raghunandan ◽  
Jasim Akber Hyder ◽  
T.P.D. Rajan ◽  
K. Narayan Prabhu ◽  
B.C. Pai
Keyword(s):  
Centrifugal Casting ◽  
Casting Process ◽  
Primary Silicon ◽  
Shrinkage Porosity ◽  
Functionally Graded ◽  
Al Alloy ◽  
Primary Si ◽  
The Difference ◽  
Silicon Particles

In the present investigation, FGMs of mono-dispersed in-situ primary Si and their hybrids with Mg2Si reinforcements have been fabricated by the centrifugal casting process using 390 commercial Al alloy. Hard primary silicon particles are formed during the solidification of the 390 alloy and Mg2Si reinforcements are formed by the addition of varying amount of magnesium into the A390 aluminium alloy. Owing to the difference in density both primary silicon and Mg2Si gets segregated towards the inner periphery during centrifugal casting. The size of the Mg2Siin-situreinforcement phase is relatively smaller and is distributed in the edges of primary silicon particles and also individually in the matrix. Thein-situMg2Si and primary silicon can significantly increase the hardness and strength of the inner periphery of the casting. Higher Mg contents have been observed to introduce significant porosity leading to poor castings. Addition of phosphorous to the melt has led to the modification and refinement of primary Si morphology and also helped in the reduction of shrinkage porosity. Maximum hardness of 167 BHN is observed towards the inner periphery of the 390Al-2.5%Mg added in-situ composite.

Effect of Copper and Magnesium on the Microstructure of Centrifugally Cast Al-19%Si Alloys

2018 ◽  
Vol 930 ◽  
pp. 484-488
Author(s):  
Chester Contatori ◽  
Antônio Augusto Couto ◽  
Jan Vatavuk ◽  
Arnaldo A. Ciquielo Borges ◽  
Nelson Batista de Lima ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Molten Metal ◽  
Centrifugal Casting ◽  
Intermetallic Phase ◽  
Outer Wall ◽  
Primary Silicon ◽  
Functionally Graded ◽  
High Wear Resistance ◽  
Centrifugally Cast ◽  
Β Phase

Hypereutectic Al-Si alloys can be used in applications that require high wear resistance. Such wear resistance is achieved by the presence of hard primary silicon particles, allied to the formation of Mg2Si intermetallic phase when magnesium is added in this alloy. Centrifugal casting generates a gradient in the microstructure of hypereutectic Al-Si alloys that can favor such applications. Cylindrical components of Al-19%Si alloy containing added copper and magnesium contents were processed by centrifugal casting. The purpose of this study is to investigate the formation and segregation of particles of primary silicon (β) and Mg2Si in Al-19%Si alloy containing additions of copper and magnesium. Because the density of silicon (2.33 g/cm3) and Mg2Si (1.88 g/cm3) is lower than that of aluminum (2.67 g/cm3), centrifugal casting causes primary silicon (β) and Mg2Si particles to concentrate more at the outer wall of the centrifuged pipe. In this study, primary silicon (β) and Mg2Si particles were found to be retained at the outer wall of the pipe. It is believed that the rapid cooling of the molten metal in the region of contact with the mold, whose temperature is lower than that of the molten metal, allied to the centrifugal force, prevented the particles from migrating to the inner wall of the pipe. The microstructure shows a gradient in the distribution of these phases, enabling the production of a functionally graded material. The addition of copper and magnesium leads to the formation of Mg2Si and Al5Cu2Mg8Si6 phases, reducing the amount of primary β phase (Si) particles. In all the evaluated conditions, a tendency is also observed for a gradual increase in the segregation of silicon towards the inner wall along the entire length of the centrifuged pipe.

Empirical Model for Dry Sliding Wear Behaviour of Centrifugally Cast Functionally Graded Al/SiCp Composite

2018 ◽  
Vol 786 ◽  
pp. 276-285 ◽  
Author(s):  
Islam M. El-Galy ◽  
Bassiouny I. Bassiouny ◽  
Mahmoud H. Ahmed
Keyword(s):  
Pure Aluminum ◽  
Centrifugal Casting ◽  
Wear Test ◽  
Functionally Graded ◽  
Wear Behaviour ◽  
Dry Sliding ◽  
Test Duration ◽  
Loading Conditions ◽  
Centrifugally Cast ◽  
Production Parameters

Horizontal centrifugal casting machine was adopted to fabricate tubes of functionally graded materials (FGM) made of commercially pure aluminum reinforced with different weight fractions of SiC particles. Tubes with 2.5, 5 and 10%wt. SiCpwere produced in the speed range 800 to 1100 rpm. Wear experiments involving dry sliding under different loading conditions were conducted on samples taken from three consecutive layers across the wall of the FGM tubes. Analysis of variance (ANOVA) was used to determine the significant FGM production parameters and wear test parameters (normal load and test duration) affecting the wear resistance of the samples. Obtained wear test results have been used to build a regression model to predict the expected weight loss across the wall thickness of the tube depending on the production parameters and the loading conditions.

Optimization of the In-Situ Al-Si Base Functionally Graded Material Fabricated by Centrifugal Casting

2001 ◽  
Vol 702 ◽  
Author(s):  
Yoshihiro Oya-Seimiya ◽  
Tetsumori Shinoda ◽  
Yoshimi Watanabe
Keyword(s):  
Functionally Graded Material ◽  
Centrifugal Casting ◽  
Functionally Graded ◽  
Outer Side ◽  
Casting Method ◽  
Graded Material ◽  
Base Composite

ABSTRACTThe fabricating conditions for the in-situ Al-Si base composite by the centrifugal casting method (CCM) have been examined. The crystallized Si particles with a lower density distribute in a gradient fashion as densely on the inner and thinly on the outer side of the wall of the cylindrical CCM-composite. Synthetically, the 25 mol% Si composite is recommended for the application like the engine liner.

Studies on Adhesive Wear Characteristics of Centrifugally Cast Functionally Graded Ceramic Reinforced Composite

2020 ◽  
Vol 17 (4) ◽  
Author(s):  
K. Kartik Sriram ◽  
N. Radhika ◽  
Manu Sam ◽  
Shrihari S
Keyword(s):  
Adhesive Wear ◽  
Centrifugal Casting ◽  
Longitudinal Axis ◽  
Functionally Graded ◽  
Dry Sliding Wear ◽  
Sliding Velocity ◽  
Cross Sectional ◽  
Centrifugally Cast ◽  
Pin On Disc ◽  
Sliding Distance

Functionally graded material containing LM13 aluminium alloy as matrix and alumina as reinforcement (10 wt. %) was fabricated (Φout150 × Φin90 × 100 mm) by centrifugal casting. Samples were machined from the cylindrical cast along its longitudinal axis. Variation in hardness along the radial cross-sectional wall revealed 33.7% improvement at the outer periphery due to higher presence of alumina. This zone was preferred for dry sliding wear experiments, designed based on Taguchi L27 orthogonal array by varying the process parameters like sliding velocity, sliding distance and load using pin-on-disc tribometer. Analysis of variance revealed velocity as most influential wear factor, next to load. An optimal condition to minimise adhesive wear was determined at a load of 15 N, sliding velocity of 3.5 m/s and sliding distance of 1250 m. Scanning electron microscope analysis on abraded surfaces showed formation of tribolayer at high velocities and delamination at high loads.

Effect of Heat Treatment on Mechanical and Tribological Properties of Centrifugally Cast Functionally Graded Cu/Al2O3 Composite

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Manu Sam ◽  
N. Radhika
Keyword(s):  
Heat Treatment ◽  
Wear Resistance ◽  
Centrifugal Casting ◽  
Casting Process ◽  
Sem Analysis ◽  
Functionally Graded ◽  
Dry Sliding Wear ◽  
Centrifugally Cast ◽  
Mechanical And Tribological Properties ◽  
Different Temperatures

A functionally graded Cu–10Sn–5Ni metal matrix composite (MMC) reinforced with 10 wt % of Al2O3 particles was fabricated using the centrifugal casting process with dimension Φout100 × Φin85 × 100 mm. The mechanical and wear resistance of the composite has been enhanced through heat treatment. Samples from of the inner zone (9–15 mm) were considered for heat treatment, as this zone has higher concentration of less dense hard reinforcement particles. The samples were solutionized (620 °C/60 min) and water quenched followed by aging at different temperatures (400, 450, and 550 °C) and time (1–3 h). Optimum parametric combination (450 °C, 3 h) with maximum hardness (269 HV) was considered for further analysis. Dry sliding wear experiments were conducted based on Taguchi's L27 array using parameters such as applied loads (10, 20, and 30 N), sliding distances (500, 1000, and 1500 m), and sliding velocities (1, 2, and 3 m/s). Results revealed that the wear rate increased with load and distance whereas it decreased initially and then increased with velocity. Optimum condition for maximum wear resistance was determined using signal-to-noise (S/N) ratio. Analysis of variance (ANOVA) predicted the major influential parameter as load, followed by velocity and distance. Scanning electron microscope (SEM) analysis of worn surfaces predicted the wear mechanism, observing more delamination due to increase in contact patch when applied load increased. Results infer 8% increase in hardness after heat treatment, making it suitable for load bearing applications.

Improvement of mechanical and tribological properties of centrifugally cast functionally graded copper for bearing applications

2018 ◽  
Vol 233 (9) ◽  
pp. 3208-3219 ◽  
Author(s):  
N Radhika ◽  
Rakesh Reghunath ◽  
Manu Sam
Keyword(s):  
Wear Rate ◽  
Coefficient Of Friction ◽  
Centrifugal Casting ◽  
Mechanical Tests ◽  
Functionally Graded ◽  
Sliding Velocity ◽  
Centrifugally Cast ◽  
Casting Technique ◽  
Mechanical And Tribological Properties ◽  
The Coefficient Of Friction

The functionally graded Cu-11Ni-4Si/10wt%WC composite and its alloy have been synthesized using horizontal centrifugal casting technique to compare the mechanical and tribological improvement and its utility for bearings and bushes. Microstructure analysis and mechanical tests showed 43% improvement in hardness and 160% improvement in tensile strength at inner radial distances compared to the outer composite periphery. Fractural analysis showed ductility for alloy, whereas for composites, brittleness at outer and a combination of both ductility and brittleness were observed at inner. Proportional rise in the wear rate and coefficient of friction was observed with increasing load and sliding distances for both composite and alloy. Composite showed a slight decline in the wear rate and coefficient of friction with an increase in the sliding velocity, while alloy showed a linear rise. Worn surfaces analysis of composite showed the formation of oxide layers, which reduced the coefficient of friction at higher sliding velocity, resulting in lower wear rate.

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