Horizontal Centrifugal Casting Research Articles

Soft and Damping Thermal Interface Materials with Honeycomb-Board-Mimetic Filler Network for Electronic Heat Dissipation.

High-power-density electronic devices under vibrations call for soft and damping thermal interface materials (TIMs) for efficient heat dissipation. However, integrating low hardness, high damping, and superior heat transfer capability into one TIM is highly challenging. Herein, soft, damping, and thermally conductive TIMs are designed and prepared by constructing a honeycomb-board-mimetic boron nitride nanosheet (BNNS) network in a dynamic polyimine via one-step horizontal centrifugal casting. The unique filler network makes the TIMs perform a high through-plane thermal conductivity (> 7.69W m-1 K-1) and a uniform heat transfer process. Meanwhile, the hierarchical dynamic bonding of the polyimine endows the TIMs with low compressive strength (2.16MPa at 20% strain) and excellent damping performance (tan δ > ≈0.3 at 10-2-102Hz). The resulting TIMs also exhibit electrical insulation and remarkable recycling ability. Compared with the commercial ones, the TIMs provide better heat dissipation (4.1°C) for a high-power 5G base station and less temperature fluctuation (1.8°C) for an automotive insulated gate bipolar transistor (IGBT) under vibrations. This rational design offers a viable approach to prepare soft and damping TIMs for effective heat dissipation of high-power-density electronic devices under vibrations.

Mechanical properties of functionally graded Al series 3000 with addition of Li 2.3 wt%

ABSTRACT One of the effective methods in increasing the device performance is the use of components made of new and advanced materials, and their physical and mechanical properties are in opposition and often lightweight. In the present study, a functionally graded (FG) pipe Al series 3000 with addition of Li 2.3 wt% fabricated by using horizontal centrifugal casting method at pouring temperature of 750°C and final round of mould of 1000 rpm (mould preheated up to 150°C). The evaluation of microstructure, hardness, compressive strength and wear resistance was done by using VEGA2 SEM, Vickers hardness test at 50 g force, Zwick Z100 test machine and pin on disc under a stress of 7.6 MPa in a distance of 1000 m, respectively. The results indicated a graded manner in the content of Li, Si and Cu from outer to inner layers of FG pipe with a density of 2.4 g cm–1. The sum of intermatallic phases in the matrix, such as β (AlLi), AlSi and Al2Cu, increased from 17 Vol% to 35 Vol%. Therefore, the hardness and ultimate compression strength of the outer layer graded in comparison to the inner layers. Also, the wear resistance of the inner layer increased 18% in comparison to that of the outer layer.

High-performance solid-state Li-ion batteries enabled by homogeneous, large-area ferroelectric PVDF-TrFE solid polymer electrolytes via horizontal centrifugal casting method

Solid polymer electrolytes (SPEs) have emerged as promising alternatives for enhancing the safety features of lithium-ion batteries (LIBs) while remaining compatible with established LIB manufacturing processes. However, a persistent challenge has been the relatively limited yield achieved via traditional fabrication techniques such as solution casting and doctor blade methods. In this study, we present a novel strategy to produce extensive and uniform films of solid polymer electrolytes using a ferroelectric polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) polymer. This approach employs horizontal centrifugal casting (HCC), a technique hitherto unutilized for SPE production. The substantial centrifugal forces generated during the HCC process yield SPE films characterized by uniform thickness across the surface and elevated ionic conductivity at ambient temperature. Compared to conventional solution casting techniques, the Li//Li cell featuring the SPE derived from HCC manifests stable electrochemical performance and increased cycle endurance. Additionally, a full cell incorporating a Li iron phosphate cathode displays consistent electrochemical behavior at room temperature. Notably, a 3 × 4 cm2 pouch cell maintains its performance attributes even under mechanical stress conditions such as folding and punching. These findings underscore the potential effectiveness of employing the HCC method in the development of high-performance SPE-based LIB systems.

INFLUENCE OF NICKEL ON THE MICROSTRUCTURAL EVOLUTION AND MECHANICAL PROPERTIES OF LM6-ALLOY-BASED FUNCTIONALLY GRADED COMPOSITE TUBES

Despite the growing demand for new materials, we used the horizontal centrifugal casting technique to synthesize functionally graded composite (FGC) tubes using an LM6 alloy containing (3, 6 and 9) w/% nickel. All the fabricated tubes were evaluated for variations in microstructure, hardness and tensile properties along the radial cross-section in three distinct zones (inner, transition and outer). X-Ray diffraction (XRD) results indicated the formation of in-situ Al3Ni in all FGC tubes, and these in-situ tri-aluminides increased further with the addition of Ni. A comprehensive microstructural analysis across the tubes utilising scanning electron microscopy (SEM) images showed that gathering in-situ Al3Ni particles keeps growing nearer the outer zone, and primary Si cuboids increase in the inner zone. This accumulation of particles improved the mechanical properties at all three zones of the FGC tubes compared to the LM6 tube having no nickel. The results of the hardness investigation showed that precipitated Al3Ni in FGCs has a beneficial impact on the enhancement of hardness. Furthermore, the observed UTS improvement in the FGC tubes was clearly associated with the precipitation and strengthening action of Al3Ni intermetallic phases, while a significant reduction in elongation has been noted. Due to the influence of centrifugal force and density variation, the tube containing 9 w/% of Ni demonstrated good gradation among composite alloy-fabricated FGC tubes, with in-situ Al3Ni particles settling largely in the outer zone and primary Si particles settling primarily in the inner zone across the radial thickness.

Wear behavior investigation of Al-B4C functionally graded composite through Taguchi's design of experiment

The present study intends to evaluate the influences of load, velocity, and sliding distance on the tribological attributes of Al6061–7.5 wt%B4C functionally graded composite material (FGCM) utilizing Taguchi's approach. The horizontal centrifugal casting following the stir casting was employed to produce the FGCM A continuous gradient distribution of reinforced B4C particles with volume fractions of 15.3%, 9.6%, 7.7%, 5.3%, and 0.5% was noticed from the FGCM structure's outside to the inner zone. Archimedes' principle revealed density and porosity decrement with increasing B4C content from the inner to outer zone. Also, the increase in hardness was observed towards the inner region. Wear tests were performed on various regions of FGCM, i.e., outer, middle, and inner, which were examined individually and analyzed by comparing scanning electron microscopy (SEM) images and energy dispersive spectrums (EDS). FGCM zones (outer, middle and inner), normal loads (10, 20, and 30 N), sliding velocities (1, 2, and 3 m/s), and sliding distances (600, 1200, and 1800 m) are the parameters investigated in this wear analysis.

Optimization and Characterization of Centrifugal-Cast Functionally Graded Al-SiC Composite Using Response Surface Methodology and Grey Relational Analysis

In this study, an optimization approach was employed to determine the optimal main parameters that improve the performance of functionally graded composites manufactured using a combination of stirring and horizontal centrifugal casting. Pure aluminum reinforced with silicon carbide particles was used as the material for the composites. The effects of key input parameters such as mold speed, pouring temperature, stirring speed, and radial distance were optimized using a combination of grey relational analysis and response surface methodology. The statistical significance of the predicted grey relational grade model was assessed through an analysis of variance to identify the appropriate main parameters. The results showed that radial distance had the greatest impact on the performance of the composites, followed by pouring temperature. The optimal combination of main parameters was determined to be a mold speed of 1000 rpm, a pouring temperature of 750 °C, a stirring speed of 150 rpm, and a radial distance of 1 mm. Confirmation tests using these optimal values resulted in a 54.69% improvement in the grey relational grade.

Improving reciprocal tribo-mechanical performance and corrosion resistance using carbide ceramics: T6 thermal-treated A333 mono-hybrid functionally graded composites

Thermally treated functionally graded aluminum hybrid composite is an innovative solution to the expanding mechanical and tribological needs of the marine industry. Through horizontal centrifugal casting, gradation of secondary (SiC) and primary (B4C) ceramics improves the reciprocal wear resistance of 6 wt%B4C/4 wt%SiC/A333 hybrid composite over 6 wt%B4C/A333 mono-composite and A333 alloy. Advanced characterization demonstrates the change in grain size and detects strengthening phases. When using a hybrid ceramic reinforcement, the microhardness and tensile strength improved by 41% and 23%, respectively, while only increasing by 12% and 10% when using a mono ceramic reinforcement. Also, hybrid and mono ceramic reinforcement reduced the wear rate by 68% and 46%, respectively. An electrochemical corrosion analysis of a saline-exposed hybrid composite showed minimal surface oxidation and pitting, making it suitable for marine tribology applications.

Simulation and experimental investigation of centrifugal-cast functionally graded aluminum-B4C composite

ABSTRACT The present work investigates the flow behavior simulation and experimental validation for Al 6061-10 wt% B4C functionally graded aluminium matrix composite (FGAMC) by varying rotational speeds in a horizontal centrifugal casting (HCC) mold. A three-dimensional computational fluid dynamics model considering particle transportation and solidification based on the multiphase volume of fluid was analyzed using Ansys Fluent software. Simulated Particle gradient formation was validated against experimental data of solidified Al/B4C FGAMC. Simulation and experimental results showed 6.06% and 8.11% thinner outer region for mold speed from 1200 to 1400 rpm respectively. On the contrary, a 27% and 37% broadened thickness was observed at the inner zone for the same. The simulation and experimentation are in good agreement, and results show the formation of B4C particles gradient from outer to inner zone of FGAMCs. In addition, the effect of centrifugal speed on solidification rate and particle distribution has been explored.

Investigation on the effect of recasting palladium-silver alloy by argon arc vacuum pressure casting process

Background/purposePalladium-silver (Pd–Ag) alloys are important as an alternative to gold-based alloys. The purpose of this study was to investigate the effect of an argon-arc vacuum pressure casting process on the recasting of the Pd–Ag alloy. Materials and methodsThe recasting Pd–Ag alloys were compared with conventional horizontal centrifugal (HC) casting to an argon (Ar)-arc vacuum pressure (Ar-arc/VP) casting. The first-generation castings were made from a Pd–Ag alloy purchased from a supplier. Next-generation castings were made from 50 wt% Pd–Ag alloy before casting and 50 wt% from previous castings. This sequence was repeated over three generations to form the 2nd, 3rd and 4th recasting ingots. The ingots were then measured for marginal accuracy, interfacial oxidation, hardness and phase identification. ResultsThe recasting success rate of recastibility reached 100%. Compared with the HC group, the Ar-arc/VP group had better edge precision, smaller oxide layer thickness and lower hardness. The comparison of X-ray diffraction intensity showed that the relative intensities of Pd and Ag in the first, second and third generations recasting of the Ar-arc/VP group were significantly higher than those of the HC group. Phase analysis showed that the trace elements of indium and tin contents in the Pd–Ag recasting ingots of the Ar-arc/VP group were higher than those of the HC group. ConclusionThe results showed that the casting process used for recasting affected the quality of the Pd–Ag alloy. Therefore, Ar-arc/VP casting process could improve the effect of Pd–Ag recasting and maintain the alloy properties in comparison with HC casting.

Experimental and numerical studies on the influence of centrifugal casting parameters on the solidification structure of Al-Cu alloy

A horizontal centrifugal casting experiment was designed to determine the change in the solidification structure of Al-Cu alloy casting and the underlying variation in temperature, then obtained interface heat transfer coefficient by inverse calculation. The continuous simulation of metal melt filling from the gate to copper mold cavity is realized. The influence of centrifugal speed, pouring temperature, and mold preheating temperature on the solidified structure was analyzed. Simulation results showed that increasing the centrifugal speed mainly enhance the solidification rate of the molten metal and then refined the solidified structure of the Al-Cu alloy. Increasing the pouring temperature and mold preheating temperatures coarsen the grain size of the casting, but the range of change is small.

Microstructure and Mechanical Properties of Vacuum Centrifugal Casted Ti-6Al-4V Alloy by Casting and Heat Treatment

The Ti-6Al-4V alloy has been widely used for structural materials due to high specific strength property, however it is difficult to cast because of high reactivity at high temperature. In this study casting characteristics and post-casting heat treatment were studied in the cast Ti alloy. The cast alloy was prepared using high-frequency induction heating and horizontal vacuum centrifugal casting to reduce reaction with crucible and mold by minimizing overheating of the molten metal and casting fast. In the thin casting with a thickness of 2 mm, α’ martensite was observed, and in the casting with a thickness of 4~8 mm, α+β Widmanstätten was observed. As the thickness of the casting increased, the grain size, α-lath width, and α-case thickness increased. Accordingly, as the thickness of the casting increased, the hardness of the matrix decreased and the hardness of the surface increased. In addition, when the casting was heat treated below the β-phase transformation temperature, the α-lath width increased, and when quenched after heat treatment in the β-phase transformation temperature region, an α’ martensite was formed. On the other hand, when the casting was heat treated in the atmosphere, it was confirmed that the elongation was very low because hydrogen and oxygen in the atmosphere were induced. In addition it was confirmed that casting defects can be removed through HIP.

Introduction of tungsten carbide into 08Kh18N10T corrosion-resistant steel and its effect on mechanical properties

Interfacial phenomena and reactions between tungsten semicarbide (W2C) and corrosion-resistant steel melt have been studied using wetting experiments. This process was followed by the method of high­temperature contact heating of W2C substrate and a metal sample made of 08Kh18N10T steel. It was established that wolfram carbide has good indicators of wettability by corrosion-resistant steel, wetting angle is 135 – 145°. Composition of the substrate surface has been studied by electron scanning microscopy to determine composition of reaction products. Analysis of the obtained results allows us to state that content of chemical elements varies over the entire contact area, but pattern of their distribution there is uniform. Due to the obtained data we can make an assumption about the applicability of combination of these components to create dispersed-hardened materials. To this end, experiments have been carried out to produce dispersedly hardened centrifugal cast blanks with various types of casting – horizontal and vertical. To obtain experimental materials, the horizontal and vertical type centrifugal casting was introduced into tungsten semicarbide ingots in an amount of 1 % wt. After producing experimental materials, a number of mechanical properties were studied, such as tensile strength, yield strength and hardness. The experimental results allow us to conclude that the use of dispersed hardening in process of centrifugal casting makes it possible to obtain metal materials with increased mechanical properties. Indicators of ultimate strength increase (for all samples on average) by 2.49 %, yield strength – by 2.27 %, hardness – by 5.02 %, which correlates with the provisions on metals physico-chemical properties when using dispersed hardening technologies.

Microscopical and corrosion studies on Al6061 − 10% Al2O3 functionally graded metal matrix composites

The objective of this work is to manufacture Aluminium reinforced with 10 wt% Alumina Functionally Graded Metal Matrix Composite (Al6061 − 10 wt% Al2O3 FGMMC) through horizontal centrifugal casting process and to investigate its microstructural and corrosion properties. The microstructure was examined along the radial direction of the FGMMC and it indicated that the gradient arrangement of reinforcements across the radial direction with supreme alumina particles reinforcement at the outer periphery. Corrosion tests were carried out on the samples cut from the outer periphery of the FGMMC using an acidic immersion corrosion test. The influence of corrosion parameters such as 1 M acidic solution (Sulphuric, Hydrochloric and Nitric acid) and immersion time (0 to 220 h) on corrosion rate was analyzed. The result revealed that the reinforcement had no effect on the corrosion rate and also the samples immersed in the hydrochloric acidic solution showed higher corrosion rate in the early period of immersion time due to the presence of chloride ions.

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.

Large-area transparent biocomposite films based on nanocellulose and nanochitin via horizontal centrifugal casting

In this study, we introduce the horizontal centrifugal casting (HCC) process that enables centrifugal force-assisted, scalable production of large-area (10 in.) polymer composite films based on nanocellulose (CNF) and nanochitin (ChNF). The HCC employs a cylinder mold with its rotation pivot being in a horizontal posture to harness centrifugal force to help flatten the film being cast, from which polymer composite films with excellent uniformity and flatness can be reliably produced in the size of the lateral surface of the cylinder mold. The combination of centrifugal force and horizontal layout of cylinder mold can allow reliable fabrication of large-area self-standing films from both polymeric solution and/or suspension in a scalable and simple fashion, which is a task not readily achieved in common film-forming techniques, such as solvent casting and vacuum filtration. We demonstrate such reliability and versatility of the HCC process by fabricating typical biocomposite films out of both a solution blend of ChNF/silk fibroin and a colloidal suspension of CNF/nanoclay as well as investigating their processing-structure-property relation as an optically transparent composite film targeting for structural component for flexible green optoelectronics and fire-retardant film, respectively.

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.

Influence of carbide ceramic reinforcements in improving tribological properties of A333 graded hybrid composites

Aluminium hybrid functionally graded metal matrix composites (FGMMCs), meet growing demands for supreme tribo-mechanical performance in automotive and aviation industry. This research experimentally compares the influence of carbide ceramics (B4C, SiC, TiC) as reinforcements, in improving reciprocating tribology performance and mechanical strength of A333 hybrid composites against alloy. Hollow cylindrical samples of A333/6 wt%B4C/4 wt%TiC and A333/6 wt%B4C/4 wt%SiC hybrid FGMMCs were developed using horizontal centrifugal casting. Metallography analysis on both composites revealed increasing ceramic gradient distribution towards outer composite wall. Particle rich zone of A333/B4C/SiC hybrid FGMMC showed maximum micro-hardness (198.9 HV) and tensile strength (267.9 MPa). Elemental mapping confirmed effective distribution of ceramics and detected elemental composition of both composites. Particle rich layer of A333/B4C/SiC hybrid FGMMC exhibited improved wear resistance in comparison with all three layers of A333/B4C/TiC hybrid FGMMC and alloy. Third-body abrasion and tribo-chemical wear were the predominant mechanisms revealed for both composites during worn surface analysis.

Characterization and Property Analysis of Heat-treated Functionally Graded Al8Si3Cu Alloy and TiC reinforced Composite

Functionally graded (FG) Al8Si3Cu alloy and 8 wt% titanium carbide (TiC) reinforced composite (∅out100 × ∅56in × 100 mm) was fabricated through horizontal centrifugal casting, followed by T6 heat treatment. Metallographic analysis confirmed fine grain structure at FG alloy outer layers, whereas heat-treated alloy displayed spheroidised eutectic silicon. Gradient microstructure was observed for FG composite. Enhanced hardness for outer layer (10.31%) and tensile strength for outer zone (58.71%) were observed for heat-treated Al8Si3Cu/TiC composite owing to the high concentration of spheroidised eutectic Si and TiC particles, compared to as-cast composite. Linear reciprocating wear analysis performed on as-cast, heat-treated alloy and composite, respectively, at varying load (10–40 N) and sliding distance (500–2000 m) confirmed increasing wear rate, with heat-treated composite having superior wear resistance. Delamination wear was the predominant wear mechanism influencing wear behaviour of heat-treated composite. The alloy and composite were characterized using X-ray diffraction (XRD), energy dispersive spectrometry (EDS), optical microscopy (OM) and scanning electron microscopy (SEM).

Centrifugally cast A356/SiC functionally graded composite: Fabrication and mechanical property assessment

Aluminum alloy with SiC particles reinforcement, functionally graded composite cylinder is developed via horizontal centrifugal casting technique. Cylindrical specimen is fabricated with 8 wt% of SiC particles reinforcement in A356 under mould rotational speed of 800 rpm. The comparative hardness at different locations on the cylinder is measured by taking five different samples along its longitudinal direction. Present investigation results shown about 204 percent improvement in hardness obtained for functionally graded cylinder at its outer region as compared to inner zone. The hardness value and its percentage of improvement shown a leaning trend from one end to other on the surface of cylinder liner. The outer layer of functionally graded material (FGM) shown about four times increase in hardness as compared to that of as cast A356 specimens. The inner layer of FGM also showed 1.3 times enhanced hardness value in comparison to A356 alloy.

Analisa Pengukuran Cylinder Liner dan Piston pada Overhoul Diesel Engine

In addition to knowing the various types of machining components that exist, operators are required to know the maintenance and be able to measure each component so that the diesel engine's performance does not experience problems that result in decreased engine performance. Meanwhile, the supporting components of the diesel engine are like cylinder liners, because the cylinder liner components determine the volume of the cylinder and the performance of the diesel engine. The shape of the cylinder liner is like a tube where the manufacturing process uses a horizontal centrifugal casting process. Horizontal Centrifugal casting process is a casting process for making cylinder liners by pouring molten metal into a rotating mold. Implementation of Top Overhaul on diesel engines is carried out by opening the cylinder head or the top of the engine. The parts examined include the rocker arm, inlet and exhaust valves, injectors, air starting valves and push rods. Top Overhaul is carried out when the working hours of the diesel engine have worked with around 6,000 hours of work. Major Overhaul maintenance, which includes inspection, maintenance and inspection carried out on all Top Overhaul works and on the piston, connecting rod, piston ring, seated metal and road metal. Major Overhaul maintenance is carried out when the diesel engine has 12,000 working hours according to the Diesel Engine Intruction Book. In the cylinder liner often occurs damage or looseness which is commonly referred to as abrasion, erosion and corrosion. Because of that the cylinder liner requires maintenance and measurement using an inside micrometer tool. From the results of the measurements and maintenance on the cylinder liner, the calculation of the consistency, taper and wear was obtained, to find out the specifications or exceed the limits specified in the Main Engine Intruction Book on the ship.