Centrifugal Casting Machine Research Articles

DESIGN AND FABRICATION OF A MANUAL CENTRIFUGAL CASTING DEVICE PROTOTYPE FOR POST COVID-19 RECOVERY GROWTH OF THE TRADITIONAL GOLD JEWELLERY INDUSTRY IN GHANA

Innovation in equipment and technology development has been identified as a powerful trigger for SMEs resilience and recovery in the context of the Covid-19 pandemic crisis. This paper presents the design, fabrication and operationalization of a simple but effective centrifugal casting device prototype, for the traditional gold jewellery industry in Ghana. The design process commenced by the conceptual design phase; detailed design phase followed by the embodiment design stage. The device was constructed using local materials. The device is easy to manufacture, maintain and relatively cheap. It can therefore be easily replicated or fabricated by ‘’wayside’’ welders. It is also easily transportable and can be used for teaching and demonstration purposes for students of tertiary institutions. The merit of this project is its innovative concept and constitutes a fundamental and important contribution to the research and development of new pioneering centrifugal casting machine for the local gold jewellery industry in Ghana.

Effect of temperature on the tribological characteristics of A356/15 wt.% SiCp functionally graded composites in unidirectional contact

In this paper, preparation of A356-15 wt.% SiC particle reinforced functionally graded metal matrix composite[FGMMC] was done using a vertical centrifugal casting machine and elevated temperature (350 °C) tribological characteristics were reported in unidirectional sliding contact. The operating parameters of tribo pair tested were fixed with a load in the range of 15 N to 45 N under a constant sliding speed of 1 m/s slid through 350 m. The gradient distribution of FGMMC disc was evaluated using optical microscopy. Hardness values were obtained from the Brinell hardness tester and found to be well correlated with the obtained microstructures. Two types of wear and friction test pins were prepared from the disc for the elevated temperature tribo testing, one obtained from the FGM's outer zone, when the particle concentration is at its highest, and another taken from the inner zone, where the matrix concentration is at its highest. According to the wear results, both test pins exhibit an increase in wear rate as the load increases. Furthermore, for all loads, it is found that the test pin from the matrix rich portion has a higher wear rate than the test pin from the particle rich portion. At high temperatures, higher coefficients of friction are seen in the pins of the matrix rich portion, while lower coefficients of friction are observed in the test pins of the particle rich portion. The SEM images reveal that for test pins obtained from matrix rich portions, adhesion and metal flow are the main wear mechanisms, and for test pins taken from particle rich portions, abrasion, delamination and severe plastic deformation. It was observed that the pin tested in the matrix-rich region generates plate-like debris, whereas the pin tested in the particle-rich portion generates powdery-type debris.

Rancang Bangun Mesin Cetak Centrifugal Casting untuk Pembuatan Pipa Komposit Geopolimer

In the field of materials engineering, various types of advanced materials have been found. This must also be accompanied by technological advances in the production process. Centrifugal casting is an effective method for casting cylindrical objects such as pipes and pressure vessels. In this research, a centrifugal casting machine is designed and made. The design process follows the steps proposed by Pahl and Beitz, starting from requirements identification, concept design, layout and analysis to the fabrication method. Furthermore, this machine was tested for casting geopolymer composite pipes. From the test results it is stated that this machine works well and can cast pipe samples at various speeds. Furthermore, the sample is cut into a three-point bending test specimen. From the test results obtained bending strength of about 50 MPa (1500 rpm tube rotation) and about 36 MPa (1200 rpm tube rotation). Thus, it is concluded that the higher the tube rotation, the higher the quality of the resulting product.

Determination of prediction model and optimization of process parameters for fabrication of Al-SiC composite using response surface methodology

ABSTRACT The study attempted to optimise the fabricating process parameters for Aluminium silicon carbide (Al-SiC) metal matrix composites (MMCs) in a centrifugal casting machine. The effects of centrifugal casting die speed, melting temperature, the wt.% of reinforcement, and particle size were investigated experimentally based on wear performance and coefficient of friction (CoF). The wt.% of reinforcement (SiC) varied from 10% to 20% and particle size from 40 to 100 µm. While the die speed and melting temperature varied from 800 to 1200 RPM and 800 to 900°C respectively. Experiments were performed according to the central composite design model. For optimisation and investigation of individual and interaction effect of each variable on wear loss, and CoF response surface methodology tool was used. The statistical study of experimental results showed that reinforcement wt.% is the most influential factor on wear, followed by die speed, particle size, and melting temperature, respectively. The increased wt.% of reinforcement, die speed, and particle size results in decreased wear loss. At the same time, the effect of melting temperature on wear loss was also observed. The effect of melting temperature on wear and CoF was the least, and an increase in melting temperature increases the wear loss, while particle size was the second most influential factor found after reinforcement wt.% on CoF. Abbreviations: MMCs Metal Matrix Composites PMCs Polymer Matrix Composites CMCs Ceramic Matrix Composites D.O.E. Design of Experiment FGMMC Functional Grade Metal Matrix Composites CoF Coefficient of FrictionCCD Central Composite Design RSM Response Surface Methodology ANN Artificial Neural Network GRA Grey Relational Analysis ASTM American Society for Testing and Materials ANOVA analysis of variance Al-SiC Aluminium Silicon Carbide

Optimization of WEDM control parameters for machining of functionally graded Al6061-10 %Al2O3 composite

Functionally Graded Metal Matrix Composites (FGMMCs) are the advanced developing engineering substance due to its different gradient properties within the single element. Machining is one of the major challenging subjects in the FGMMCs due to its hard ceramic particles. The objective of this experimentation is to make aluminium reinforced with 10% alumina (Al2O3) FGMMC using Horizontal centrifugal casting technique and machine the fabricated specimen using Wire Electric Discharge Machining (WEDM) with varying levels of control variables such as wire feed rate (1, 2 and 3 mm/min), pulse on time (1, 2.5 and 3 μs) and pulse off time (12, 16 and 18 μs). Optimization was performed to derive the optimal output responses such as highest Material Removal Rate (MRR) and smallest Surface Roughness (Ra) using Taguchi’s technique. The optimum operation parameters obtained from this study to get the highest MRR are wire feed rate 2 mm/min, pulse on time 3 μs and pulse off time 18 μs and smallest surface roughness are wire feed rate 1 mm/min, pulse on time 3 μs and pulse off time 12 μs.

The impact of centrifugal casting processing parameters on the wear behaviour of Al alloy/Al2O3 functionally graded materials

In this study, a vertical centrifugal casting machine has used for the fabrication of a functionally graded material (FGM) which has prepared by a non-commercial pure aluminium (>97.9% Al) with Al2O3 reinforcement particles were produced at different speeds rang 800 rpm and 1200 rpm. The reinforcement was varied with different volume percentage such as 3, 4.5, 6, and 7.5 vol.% A Pin on the Disc tribometer has used to investigate the sliding wear behaviour of metal matrix composites. The disc speed was kept constant (0.5 m/s) during the wear test, with a load was 30 N at room temperature. The disc as a counter body has made of AISI 52100 steel. For wear testing all specimen has prepared as per the ASTM standards. Establish wear test outcomes have been used the weight loss method across the inward to outward of the cast ring, which depends on the fabrication parameters, sliding distance, velocity, the loading conditions also exhibited in the Scanning Electron Microscopy analysis and micro hardness in that region.

Investigation of the microstructure and thermo-mechanical properties of functionally graded materials fabricated by the vibrating centrifugal solid particle method

In this research, SiC/Al A413.1 functionally graded materials (FGMs) were fabricated by the vibrating centrifugal solid particle method (VCSPM), and the effects of the SiC particles on the microstructure and thermo-mechanical properties of an A413.1 aluminium alloy were investigated. The benefits of a vibration during centrifugal casting of FGMs are illustrated. After designing and fabricating the centrifugal casting machine, cylindrical FGM specimens were produced using the centrifugal solid particle method (CSPM) and VCSPM. This study used SiC particles with an average particle size from 50 to 62 μm as reinforcements to fabricate A413.1-10 wt% SiC functionally gradient composites at three annular mould speeds (900–1500 and 2100 rpm) and with or without a vibration of the mould. The Brinell hardness was measured; the yield strength (YS), ultimate tensile strength (UTS) and Young’s modulus (E) were determined by tensile testing; the density was determined by the Archimedes method; and the thermal expansion coefficients were measured with a dilatometer. A comparison of the samples produced by the conventional method and VCSPM shows a significant reduction in the porosity and an increase in the distribution gradient of the reinforcing particles for the VCSPM case. It can be concluded that in both processes, the mechanical and thermal properties improved in most cases by moving from the inner radius to the outer radius because of the movement of particles towards the outer radius from the centrifugal force. The results also show that the use of a vibration dramatically increased the rate and speed of migration of gas bubbles towards the inner radius, and the mechanical properties (hardness, YS, UTS and E) improved by moving from the inner to outer radius due to an increase in the percentage of silicon carbide particles. Upon increasing the velocity and using the VCSPM, the slope of these changes becomes steeper than those for the vibration-free mode and at low rotation speeds.

A Preliminary Study of Fabrication Technology for Dynamic Compression Plates Using Centrifugal Casting Process

The high cost of health services in low-income countries has caused them to produce implants and medical devices at low cost. This research highlights a preliminary study of the design concept, mould design, and fabrication of horizontal type centrifugal casting machines for the manufacture of dynamic compression plates materials. Normally, dynamic compression plate is produced from materials such as 316L stainless steel, cobalt, and titanium alloys. In this work, aluminium-silicon alloy was used in this preliminary study. Aluminium-silicon alloy was melted at a temperature of 730 °C and poured into a mould with a rotational speed of 1500 rpm. Tensile, hardness and microstructure investigation were carried out to discern the mechanical properties of the cast product from the horizontal type centrifugal casting machine. Results showed the measured value of tensile strength is not significantly different in the two zones of cast pipe, the butt zone of fall of molten metal (specimen A) was 147 MPa, and the butt-end zone (specimen B) was 142 MPa. The hardness value for the as-cast pipe obtained from the outside, middle, and inside, was 104.0, 92.9, and 80.3 HV, respectively. Evaluation of microporosity in fractures (from tensile test) results from horizontal type centrifugal castings showed a small distribution. Meanwhile, the calculation of the contour hole processing time for DCP with eight holes is 38 minutes per implant.

Fabrication and dry sliding wear analysis of centrifugally casted A 356-10% SiCp functionally graded metal matrix composites at different rotational speeds

Functionally graded materials (FGMs) are advanced composite materials characterized by their variation in the composition or microstructure in a specific direction. The composition of FGMs is continuously varying. The desired properties can be achieved in a single bulk material of FGM which makes them especially applicable for mechanical and tribological applications. Using a vertical centrifugal casting machine fabrication of aluminium A 356-SiCp functionally graded metal matrix composites (FGMMC) were done. 10% by volume of SiCp particle were taken. An average size of 34 μm is chosen for additive SiCp, so that dispersed particulate matter in matrix of A-356 will enhance mechanical and tribological properties such as wear resistance, ultimate strength and hardness. The castings were carried out at 1100 rpm, 1200 rpm, 1400 rpm, 1550 rpm, 1700 rpm and 1950 rpm of the machine. The microstructural analysis projects a good gradation at 1700 rpm. The observations are validated using hardness analysis. Dry sliding wear behaviour of FGMMCs fabricated at rotor speeds of 1550 rpm, 1700 rpm and 1950 rpm were done. Hardness improvement at outer radial position than that of inner radial position of FGMMCs are 1.19, 1.29, 1.35 and 1.54 times at speeds 1400, 1550, 1700 and 1950 rpm of the machine respectively. The casting at 1700 rpm showed a good gradation at transition region compared to others. Wear resistance at outer surfaces of FGMMCs are improved with the presence of SiCp at the expense of COF.

The effect of pouring temperature on the tensile strength and micro structure of Al alloys by centrifugal casting

There are many ways to overcome the leaking pipes in pipe joining; one of them is by using centrifugal casting as method for its production. The goal of this study is to know the effect of pouring temperature on the tensile strength and microstructure of centrifugal casted pipe product. We tried to produce the pipe at temperature of 680°C, 700°C and 720°C, with the constant rotation speed of the centrifugal casting machine (1500 rpm). The tensile test was done based on standard of ASTM E8. The results show that the highest tensile strength is obtained from the product that was manufactured at 680°C (136.3 MPa) and the lowest is at 720°C (115.3 MPa). These data are supported with the result of microstructure test which revealed that the amount of Al dendrite structure is more homogenous and uniform when the pouring temperature is closed to melting point.

Possibility of using yttrium oxide powder as a strengthening phase for centrifugal casting of corrosion-resistant steels

The authors have made an analysis of necessity to improve the composition of the existing structural materials for critical purposes in the direction of creating metal matrix materials, which combine a highly plastic metal base and refractory high-strength high-modulus fillers. For iron matrix alloys, dispersed yttrium oxide (Y2O3 ) particles are preferred because of their stability at pyrometallurgical process temperatures and inertness to alloy components. The technology of obtaining new materials by introducing dispersed particles into a liquid melt during casting using a centrifugal casting machine to obtain a hollow (pipe) billet is considered. The possibility of increasing the mechanical and operational properties of metal matrix materials in comparison with monomaterial is shown. The article describes results of the thermodynamic modeling of high-temperature processes occurring in the yttrium oxide - metal matrix (melt) system. Modeling was carried out using the FactSage software package. A composition corresponding to 12Cr18Ni10Ti steel was used as the modeling composition of the matrix material. The calculations were made according to the ratio of 1 g of yttrium oxide additive per 100 g of matrix metal melt. From the simulation results it is possible to conclude that the introduced dispersed yttrium oxide powder does not interact with the alloy components, does not dissociate, and does not undergo allotropic transformations. The expediency of conducting experiments on the production of centrifugal castings using yttrium oxide as a hardening phase with the aim of a possible increase in radiation resistance is shown. Directions are indicated for developing the most effective technology for creating metallic materials based on an iron matrix dispersed-hardened by yttrium oxide.

Influence of Reinforcement of TiC Particles on Wear Behaviour of Al7075/TiC Composite Material

TiC particles are reinforced with Al 7075 to develop metal matrix composite. Special purpose die is fabricated for centrifugal casting machine for the preparation of composite material. The tribological properties such as wear rate and coefficient of friction are determined by using pin on disc wear testing machine. Weight percentage of TiC, applied load, sliding distance are considered as parameters for the wear test. The results show that the wear resistance of the developed composite increases with increase of TiC percentage. Wear rate of Al-TiC composite is observed to be reduced by 11%, 31% and 42% with increasing percentage of TiC by 2.5%, 5% and 7.5% respectively. SEM and EDS analysis are used for morphological study of the worn surfaces of composite. Keywords: Composites, Al-TiC, Wear, Coefficient of Friction (CoF), SEM

Investigations on the Melt Flow Behavior and Microstructure of A390 Alloy During Vertical Centrifugal Casting Process: CFD Simulation and Experiments

In this study, vertical centrifugal casting process is used for the fabrication of functionally graded A390 alloy hollow cylinder and Mg & Sr-included A390 alloy hollow cylinder. The commercial CFD software FLOW3D™ is used to obtain the optimum rotational speed for making an optimized hollow cylinder in a vertical centrifugal casting machine. The optimum rotational speed obtained is 1300 rpm. This rotational speed is used in the experiments to obtain hollow cylinders of optimized thickness for (a) A390 alloy (b) by adding various weight percentages of Mg and Sr in A390 alloy. The optical microstructures obtained at various radial locations are presented for centrifugally cast A390 alloy. The effect of individual addition of Mg & Sr into A390 alloy on the microstructures at various locations along the radial direction of centrifugally cast cylinder is discussed in detail.

Fabrication and characterization of centrifugally cast functionally graded A 356-SiCp metal matrix composites

Functionally graded materials (FGMs) are inhomogeneous materials which consist of two or more materials. FGM are engineered to have continuously varying spatial composition profile. Vertical centrifugal casting machine is used to cast the A 356 aluminium alloy FGMMC with 5% and 10% percentage by volume SiCp as reinforcing particle. Rotational speed of the machine is kept at 1700 rpm. The size of the SiCp is about 34 μm. The particulate matter is dispersed in the matrix of A 356 which will enhance properties such as hardness, strength and wear resistance through dispersion hardening. Comparison of the density, hardness, ultimate strength, sliding wear and coefficient of friction of FGMMCs were done. The hardness of the composite at the outer region increased about 1.19 times than the base alloy for A 356–5% SiCp FGMMC, 1.35 times for A 356–10% SiCp FGMMC. Ultimate strength observed at the outer periphery are 256 MPa and 263 MPa respectively for 5% and 10% SiCp FGMMCs. Presence of SiCp particles increase the wear resistance and the coefficient of friction. The wear resistance is inversely proportional to sliding velocity and load.

Investigation of Low Rotational Speeds Effect during Centrifugal Casting on the Mechanical Properties of Polymer Composites Material

In this article, we present our developed and manufactured centrifugal casting machine. We present the results of mechanical testing of samples from polymer composites made on it. At the beginning we give an overview of the main trends in the market of polymer composites. We consider the main factors affecting the mechanical characteristics of polymer composites, and determine the main limitations of using centrifugal casting technology for polymer composites. In conclusion, we give directions for further research. Many industries use polymer composite materials (PMC) to meet production needs. The main advantage of PMC is the possibility of obtaining high strength with relatively low weight, as well as the possibility of obtaining additional necessary properties, such as dielectric, magnetic, etc. The PMC market continues to grow, and now PMC is widely used in aircraft manufacturing, automotive, medicine, etc. [1]. Despite the positive aspects of using PMC, this method has some drawbacks. Firstly, low automation of the process of casting parts from PMC. Many technologies are quite difficult to automate due to their process complexity and constant monitoring. Development in this direction is already underway, and there are practical solutions, such as automatic tape placement (ATL) / automatic fiber placement (AFP) [2]. On the other hand, the cost of these solutions is quite high. Secondly, the high cost of the equipment and tooling manufacturing. Such technologies as pressing, pressing and autoclave molding using prepregs are attached to certain technological equipment and need to organize pressure, maintain temperature, etc. This increases the range of equipment used and overall process complexity. In some technologies using high pressure and heat-cooling such as pressure casting (RTM) [3], it is necessary to use high-strength steels for molds, the processing of which takes a long time and wears the tool. Thirdly, increased knowledge-intensive work and high requirements for staff qualifications [4]. Manufacturing products from PMC requires careful monitoring by the technologist, since the influence of such parameters as: temperature, pressure will affect on the product structure and, accordingly, its characteristics. Fourthly, loss of strength after cutting operations (such as drilling, milling, taping and so on) and further stratification of PMC [5]. This leads us to the fact that used technology should maximally ensure the product geometry with minimization of subsequent post-processing.

Simulation Study on Filling and Solidification of Horizontal Centrifugal Casting Babbitt Lining of Bimetallic Bearing

A continuous flow model to simulate the horizontal centrifugal casting was built based on the numerical simulation technique of filling and solidification processes, which realized the continuous simulation of the metallic melt from the pouring gate to the mold filling in the cavity of the steel back. The effects of different rotate speeds, pouring rates and cooling methods on the filling process and the solidification temperature field of centrifugal casting Babbitt lining were studied. The results show that the rotate speed and the pouring rate mainly influenced the flow states of the molten metal in the filling process. The cooling method decided the solidification rate and then affected the microstructure of the casting. The defects of the Babbitt lining manufactured by horizontal centrifugal casting machine were found to occur in the final solidified region of the simulation model. The simulation model built in this paper is designed to guide the improvement in the actual process.

Optimization of Centrifugal Casting Parameters of AlSi Alloy by using the Response Surface Methodology

Centrifugal casting is one of the advanced casting branches widely used in the metallurgical industry in which the centrifugal force helps strengthen the workpiece material. The present work attempt to study the effect of the horizontal and vertical centrifugal casting parameters included the centrifugal mold rotation speeds and G-factors values on the quality of the product. The work has been completed with design and fabricated of a low cost horizontal and vertical centrifugal casting machine with the main accessories for producing a hypoeutectic aluminum silicone (AlSi) alloy (content 10 % Si) specimens. The experimental results were analyzed and improved by using the statistical computer program “Design Expert 11” and response surface methodology (RSM). The results showed that for vertical and horizontal casting processes, the finest surfaces quality was achieved when working at mold rotation speed from 520 to 690 and 950 to 1230 RPM, i.e., with an average value of the G-factor = 69 and 50, respectively. The proof stress values were increased with increasing the mold rotation speed up to (690 RPM) and (1230 RPM) or used the G- factor value of 87.99 and 60.96 gave an increase in proof stress by 6.7 and (20.62% for vertical and horizontal casting experiments compared with gravitational casting, respectively. The obtained tensile strengths values were improved by 38.6 and 45.41 %, compared with the gravitational casting, respectively; while the percentage elongations were reduced to 0.281and 0.291 %; which means decreased by 33.45 and 31.69 % for the vertical and horizontal centrifugal casting compared with the values obtained by gravitational casting experiments, respectively.

Metals Property Changes Under Effect of Vacancy-Cluster Structures

The experimental results analysis of a metals property changes under vacancy-cluster structure effects are shown. Two technological approaches of such structures obtaining are considered. The first is a nanopowders compaction under high (up to 5GPa) hydrostatic compression, on example of a Ni nanopowder (70nm). The second is the Al and Pb crystallization under the high-intensity plastic deformation [e¢ = (102-104) sec-1] (НIPD) conditions on the solid-liquid boundary in the centrifugal casting machine with rotary speed up to 2000 rpm. Using the method of atomic force microscopy (AFM), vacancy cluster tubes (VCT) with average diameters of 39 nm for Al and 25 nm for Pb have been detected in the crystallized volume of Al and Pb metals. Discussed the physical model of a new substructure formation within the metals in the form of vacancy cluster tubes, obtained in the process of high-intensive plastic deformation (HIPD) during the process of mass crystallization of Al and Pb and the changes in the mechanical, magnetic and superconducting properties of the above metals, which followed this process. During Al and Pb crystallization under high-intensive plastic deformation (HIPD) range about [e′ = (102–104) sec-1] with specially selected modes of metals crystallization in high-speed centrifugal casting machine the special conditions are being created to achieve the dimensional effect of dynamic (shifting) re-crystallization. Shifting deformation during centrifugal crystallization caused primarily by a large incline of the temperature field from the periphery (relative to the cold wall of the rotor) to the molten central part of the rotor. The difference in the angular velocities of the already-frozen part of the metal (adjacent to the outer surface of the rotor wall) and the central part, where the metal still remains in the molten state, leads to a high-intensity deformation [e′ = (102–104) sec-1] of the crystallized metal melt solidified phase. Since the grain sizes at the crystallized phase initially comprise around tens of nano-meters (approximately crystal nucleation size), it becomes possible to achieve the dimensional effect of the dynamic re-crystallization of a «nanocrystalline» solidified metal at high shift of strain velocities. The ≪non-equilibrium vacancies≫ formed this way condense into vacancy clusters, which are formed in the centrifugal force field in the form of vacancy-shaped cluster tubes stretched out to the center of rotation of the rotor. The process proceeds under conditions far from the equilibrium in comparison with the usual crystallization of the metal from the melt. Such processes can lead to the formation of highly ordered non-equilibrium statescharacteristic of non-equilibrium open systems. Discussed the physical model of a metals vacancy-cluster structures formation at high hydrostatic nanopowders compression (up to 5 GPa) and high-intensity plastic deformation (HIPD) at the stage of Al and Pb alloys mass crystallization during centrifugation. Conclusion of the article is that the high-intensity plastic deformation (НIPD) at the melt crystallization stage against a background of high stationary nonequilibrium vacancies concentration brings to the new type of the elements structure formation - vacancy cluster tubes (VCT). A comparative analysis of mechanical, magnetic and superconducting properties changes for structured metals introduced.

Development of lotus-type porous material for heat pipe application using centrifugal slip casting process

Heat pipe is a heat conductor which has a large conduction capacity using a special fluid-filled pipe as a conductor of heat from the hot end (evaporator) to the cold end (condenser) used for thermal management. In the heat pipe, there is a sintered wick which transfers refrigerant fluid from condenser to evaporator. The objective of this research is to improve capillary performance by making a straight pore called as lotus-type porous material (LTP) using centrifugal slip casting technique. Copper powder is used as wick materials due to its high thermal conductivity. A starch solution is used as binder material to make the copper slurry. Nylon wire is applied as straight pore mold. Freeze drying is applied to curing and demolding. Vacuum sintering is conducted to increase metallurgical bonding between the particle. The results show that centrifugal casting machine is capable to make a wick with LTP structure. On the performance department, capillary pumping is affected by rotation speed, powder size, and powder loading. The optimum parameters were copper powder with 260.54 μm powder size, 50% Powder Loading with 688 rpm rotation speed. The LTP wick is proved to have a higher capillary pumping capacity compared to the conventional wick. Further work is necessary to verify the performance of LTP wick in the heat pipe.

Empirical Model for Dry Sliding Wear Behaviour of Centrifugally Cast Functionally Graded Al/SiC<sub>p</sub> Composite

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. SiCp were 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.