Casting Simulation Software Research Articles

Automated optimization of gating system through numerical simulation

Casting is a process for the production of complex shapes. Defects are unavoidable in any casting process. An efficient method of eliminating such defects can improve the process capability of the casting system. Computer simulation can save time, resources, and money in foundry trials, but it necessitates more human effort in terms of preparing the inputs and appropriately interpreting the results. In this work, a new method for evaluating and optimizing gating system design utilizing a simulation tool is proposed. It is possible to automatically modify the gating design with the help of CAD and casting simulation software from a given initial design and boundary conditions, and to check whether the design is effective to eliminate defects. Further this takes less human effort, making it more useful for industrial applications. The suggested methodology is demonstrated by autonomously optimizing the gating system for two industrial components and validated by producing actual castings made in sand molds.

Design and Development of LM24 plate Casting using Solid Cast Simulation Technique

Abstract: This research deals with the elimination of defects in aluminium alloy castings and enhancement in the casting yield and quality. The main intention of the work is to improve the quality of a cast component using Computer Aided Casting Simulation Software. SOLID Cast simulation software is used for simulating the solidification process of casting and visualizing outputs showing possible problematic areas or defects which may occur in the cast product. Plate Castings of aluminium alloy - LM 24 are produced with different designs of gating systems and tested for defects like porosity using Archimedes immersion Technique and also Radiographic testing is used to check the quality of the castings. The produced castings are observed to be sound, and the results obtained are in agreement with the simulation results. Hence it is verified that solidification simulation helps in improving the quality of castings without any shop-floor trails. Casting yield and percentage porosity values are determined for 12 castings produced with different gating systems. The best results are observed to be produced by the castings having a 1-Ingate system in horizontal or lateral positions.

Investigation of the Effects of Filling Speed, Casting Temperature and Metallurgical Quality on Fluidity of Lamellar Graphite Cast Iron at Different Section Thicknesses

AbstractIn this study, the fluidity properties of the alloy were investigated at different casting temperatures, different section thicknesses, and varying casting parameters of lamellar graphite cast iron materials. To achieve our goal, we utilized sand molds that were created with specific parameters including pouring temperature, metallurgical quality, section thickness, and fluidity test model. These molds were used for casting. Thus, the effect of fluidity properties in changing casting conditions and liquid metal advance distances at determined section thicknesses was investigated. Modeling was carried out with FlowCast casting simulation software by determining the liquid metal advance distance depending on the section thickness in the castings made in sand molds under changing casting conditions. The fluidity and advance distance of the liquid metal was determined comparatively with experimental and modeling techniques under the changing casting conditions in the parameters determined in this study. When the outcomes were examined; it was observed that different liquid metal advance distances occur at different cross-section thicknesses depending on the changing conditions.

Embedded measurement of process monitoring in melt-cast explosive based on distributed optical fiber sensing and numerical verification

The solidification sequence during the solidification of fusion-cast explosives is an important parameter for the optimization of the manufacturing process, which can be analyzed by using numerical simulation experiments. However, the numerical simulations are not totally reliable due to the inherent errors in the algorithms and parameters. To address this issue, a measurement method is proposed to monitor the solidification process based on the embedded method of distributed fiber optic sensing. And a method is developed to identify the solid–liquid phase change interface region, which can be effectively demodulated and analyzed for sensing data. The experimental results were verified by using numerical simulations based on casting simulation software and compared. It can be found that the total solidification time and pattern of both are relatively consistent. However, some of the solidification characteristics in the numerical simulation are lack of precision due to the inaccuracy of the heat transfer parameters.

The efficiency of multithreaded computing in casting simulation software

The utilization of computer simulation software for casting process simulation is becoming essential in the advancement of casting technology in aviation and other high-tech engineering fields. With the increase in the number of computational cores in modern CPUs, the use of multi-threaded computations is becoming increasingly relevant. In this study, the efficiency of multi-threaded computations in modeling casting processes was evaluated using finite element method casting simulation software ProCast and PoligonSoft, which utilize parallel computing architectures with distributed (DMP) and shared (SMP) memory, respectively. Computations were performed on Intel and AMD-based computers, varying the number of computational threads from 4 to 32. The calculation efficiency was evaluated by measuring the calculation speed increase in the filling and solidification of GP25 castings made of ML10 alloy, as well as the complex task of filling and solidification modeling nickel superalloy casing castings with radiation heat transfer simulation. The results indicate that the minimum computation time in ProCast software is observed when using 16 computational threads. This pattern holds true for both computing systems (Intel and AMD processors), and increasing the number of threads beyond this point does not make a practical difference. The performance decrease in this scenario can be attributed to the low-performance energy-efficient cores in systems based on Intel processors or the decrease in core frequency and full loading of physical cores in systems based on AMD processors. Multi-threading the modeling task in PoligonSoft software is less efficient than in ProCast, which is a result of the shared-memory architecture used in PoligonSoft. Despite the significant difference in parallel efficiency, the task of GP25 casting solidification in both PoligonSoft and ProCast is solved in a time close enough to be considered sufficient.

Predicting the local solidification time using spherical neural networks

Castings are predestined for the application of structural optimization, but to date, the integration of process simulation into structural optimization is limited due to high computational cost and is therefore often neglected at the beginning of the design process. This leads to the need for surrogate models, which allow a fast and simplified evaluation of design proposals during the optimization in order to improve the integration. This article introduces a novel approach that estimates the solidification time of randomly created geometries solely based on the casting geometry. The approach uses ray-tracing methods to calculate the distance function along preset directions. The estimated solidification time is calculated using a Spherical Convolutional Neural Network (CNN). The training data is obtained by several thousand solidification simulations using the optimization toolkit of a commercial casting simulation software combined with further data augmentation. The model is experimentally validated for five different geometries in the sand casting process.

Investigation of metallurgical properties of Al-Si-Mg casting alloys with integrated computational materials engineering for wheel production

In this study, integrated computational materials engineering, which is one of the new generation approaches in materials science, was used in the production of aluminum alloy wheels by low pressure die casting method. In casting alloys, the efficiency of grain refinement provided by master alloys added to the melt decreases with increasing silicon content of the alloy. In this context, as-cast properties of silicon reduced (Si: 5.0 wt.%) alloys with different Mg ratios (Mg: 3.0, 5.0, 7.0 wt.%) are discussed using integrated computational materials engineering approaches. It has been evaluated whether the examined alloys can be an alternative to the AlSi7Mg0.3 alloy, which is currently used traditionally in the production of aluminum-based wheels, with their microstructural and mechanical properties. The study consists of three stages which are computer-aided production, pilot production, testing and characterization studies. In computer-aided production, original sub-eutectic compositions were determined in types and amounts of alloying elements, alloy designs were realized and a database was created with a computational materials engineering software. Then, low pressure die casting analysis were performed in a virtual environment by transferring these data directly to the casting simulation software. Thus, the microstructural and mechanical properties of the wheel were obtained computationally on the basis of the varying alloy composition. In the second stage, the virtually designed alloy compositions were prepared and sample wheels were manufactured by the low pressure die casting method on an industrial scale. In the testing and characterization phase, spectral analyses, macro and microstructural examinations, hardness measurements and tensile tests were carried out. As a result of this study, it was determined that the studied alloys could be used in the production of wheels by the low pressure die casting method considering the metallurgical properties expected from the wheel. In addition, it is thought that the mathematical design of the material with integrated computational materials engineering approaches before casting simulations will play an active role in the competitiveness and sustainability of the aluminum industry in technological conditions.

Simulation Based Fluidity and Solidification Analysis of Aluminium-Copper Sand Cast Alloy

Aluminium-copper alloys are known for their very good strength at high temperature .Addition of copper improves the strength at high temperatures due to precipitation strengthening. Fluidity in casting is the major factor which affects the cast quality of the final components. Addition of Silicon with copper in Aluminium improves fluidity and finally quality of the cast components. But presence of Silicon adversely affects the strength at high temperature. In the present work cooling curve analysis of Al-Cu alloy (without Silicon) is done for different wt% of copper addition. The current study for Al-Cu alloy is based on sand casting method as it is one of the cost effective manufacturing method. Cooling curve obtained from the simulation results used to predict the fluidity, microstructure of the alloy when copper wt% is varied. Predicted microstructure and grain structure from the cooling curve goes well with the microstructure studied from shop floor casting .In the present work “Z-cast” casting simulation software is used for casting simulation. Among three different alloy composition studied aluminium with 8% copper gives the best results when compared on the basis of grain size .But fluidity analysis reveal poor fluidity for the alloy having 8 wt% of copper. The current analysis helps to study the optimum aluminium –copper alloy composition that can be used in high temperature applications.

Redesigning and numerical simulation of gating system to reduce cold shut defect in submersible pump part castings

Gating system design is an essential element in casting that significantly affects the melt's molten metal flow behaviour, heat transfer, and solidification. Improper gating system leads to pouring-related defects like cold shut, misrun, etc. Submersible pump-bearing block castings produced in one of the leading foundries are rejected due to a cold shut defect. It was identified that the improper gating system is the probable cause for rejection. The bearing block and the existing gating system were modelled in 3D modelling software, and the molten metal flow behaviour of casting was simulated with casting simulation software. Based on the simulation results, the existing gating system was redesigned following established empirical relations. The component with the revised gating system was analysed for flow behaviour through simulation with the software. With the revised gating system, elimination of cold shut is observed, and the revised gating design is recommended to the industry for implementation. The effectiveness of the revised gating system is also validated with pump diffuser casing, which has similar geometrical and material characteristics. The simulation results and experimental validation showed a reduction in flow and surface defects. Appropriate design of the gating system and balanced arrangement of cavities in the gating system are noted to reduce the flow and surface-related defects. It is observed that with the revised gating systems, the percentage of rejection is reduced from 28.36% to 2.34% and 23.43% to 2.45% for the bearing block and pump diffuser casing respectively.

Research on the low-pressure casting process of a double suction impeller in 304 austenitic stainless steel with high performance and thin-wall complex structure

The manufacturing of thin-wall complex castings using pressure-assisted casting is one of the most significant challenges for structural applications requiring excellent mechanical properties and fuel. In this paper, efforts have been made to manufacture thin-wall complex structure casting using high-temperature alloys with high strength. Low pressure casting forming process was used to manufacture a double suction impeller in 304 austenitic stainless steel with a thin-wall complex structure. By combining 3D printed sand mold with an optimized low-pressure casting process, a double suction impeller with a thin-wall thickness of 3mm was successfully prepared. The prepared double suction impeller showed structural integrity, smooth surface, and compact structure. The filling and solidification process of the 304 austenitic stainless-steel melts were analyzed using casting simulation software. The casting had an excellent mechanical property with a tensile strength of 595 MPa, yield strength of 265 MPa, and elongation of 48%. Results show that the improved low-pressure casting processes could be applied to the production of thin-wall complex structure parts during high-temperature casting processes. The results are of great significance to the casting of high-temperature alloys.

Shrinkage porosity prediction empowered by physics-based and data-driven hybrid models

Several defects might affect a casting part and degrade its quality and the process efficiency. Porosity formation is one of the major defects that can appear in the resulting product. Thus, several research studies aimed at investigating methods that minimize this anomaly. In the present work, a porosity prediction procedure is proposed to assist users at optimizing porosity distribution according to their application. This method is based on a supervised learning approach to predict shrinkage porosity from thermal history. Learning data are generated by a casting simulation software operating for different process parameters. Machine learning was coupled with a modal representation to interpolate thermal history time series for new parameters combinations. By comparing the predicted values of local porosity to the simulated results, it was demonstrated that the proposed model is efficient and can open perspectives in the casting process optimization.

Failure analysis of a clutch wheel for wind turbines with the use of casting process simulation

Production of high-quality and high-grade casts at the lowest possible cost is a priority of every foundry. Innovation and optimization of the currently applied production processes is a necessary step to achieving such a goal. Costly and long experiments performed in real foundries may be replaced with numerical simulations, as they provide reliable representation of the casting process using the computer technology. A detailed analysis of simulation results facilitates forecasting various risks that might negatively affect the quality of produced casts, and hence the quality of the entire production process. The present article discusses the effects of adjustments to the design of a gating system on the quality of a cast made of EN-GJS-500-7 ductile cast iron, which is used as a clutch wheel in turbines in wind power plants. During the production of the cast, two models of the gating system were created in Solid Works CAD software. The gating systems were validated using NovaFlow&Solid casting simulation software. The modification of the gating system design resulted in a reduced amount of liquid metal used for casting, which has significant economic effects in the mass production. Eight simulations of the designed gating systems were carried out. The main purpose of the simulations was to determine the mesh density as well as the casting and solidification conditions so that they are as close as possible to the real conditions in a foundry. Subsequently, the gating system was modified with the result of eliminating defects in the cast that occur during the solidification process as well as increasing the utilization of liquid metal.

Optimal Experiment Design for the Identification of the Interfacial Heat Transfer Coefficient in Sand Casting

The interfacial heat transfer coefficient (IHTC) is one of the main input parameters required by casting simulation software. It plays an important role in the accurate modeling of the solidification process. However, its value is not easily identifiable by means of experimental methods requiring temperature measurements during the solidification process itself. For these reasons, an optimal experiment design was performed in this study to determine the optimal position for the temperature measurement and the optimal thickness of the rectangular cast iron part. This parameter was identified using an inverse technique. In particular, two different algorithms were used: Levenberg Marquard (LM) and Monte Carlo (MC). A numerical model of the solidification process was associated with the optimization algorithm. The temperature was measured at different positions from the mould/metal interface at d = 0 mm (mould/metal interface), 30 mm, 60 mm and 90 mm. the thicknesses of the cast part were: L1 = 40 mm, 60 mm and 80 mm. A comparative study on the IHTC identification was then carried out by varying the initial value of the IHTC between 500 Wm−2K−1 and 1050 Wm−2K−1. Results showed that the MC algorithm used for estimating the IHTC gives the best results, and the optimal position was at d = 30 mm, the position closest to the mould/metal interface, for the lowest thickness L1 = 40 mm.

Experimental model of the pearlite interlamellar spacing in lamellar graphite iron

The pearlite lamellar spacing (λpearlite) is one of the microstructure parameters that define the strength of the lamellar graphite iron (LGI). The transformation kinetics of λpearlite has been the subject of several modeling studies for steels, which demonstrated that the λpearlite can be calculated as a function of undercooling. However, it is hard to find in the literature the models for the prediction of λpearlite in LGI. In the present work, λpearlite in fully pearlitic LGI was investigated for a wide range of carbon contents and cooling rates. The undercooling and the cooling rates were estimated from the experimental cooling curves and were utilized for the prediction of λpearlite. The experimental data analysis provides an empirical expression that correlates λpearlite and cooling rates from the eutectoid transformation region. The developed empirical model was incorporated into a casting simulation software to enable the prediction of λpearlite in LGI and the simulation results were found to be in good agreement with the experimental data.

The effect of micro-nano TKX-50 particle gradation on the properties of TNT based castable explosives

ABSTRACT Dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) is an energetic ionic salt that has many advantages over conventional explosives, including high detonation speed, high energy, and low toxicity. Although the properties of TKX-50 have been explored in many aspects, TKX-50/2,4,6-trinitrotoluene (TNT) based melt cast explosives are not yet reported. Herein, this work investigated the application of TKX-50 in melt cast explosives by using TNT as the dispersant and TKX-50 as the high-energy component. The effect of micro-and nano-sized TKX-50 particles on the properties of the castable explosives was investigated. The TKX-50-based castable explosives were characterized through scanning electron microscopy, X-ray diffractometry, differential scanning calorimetry, velocity of detonation measurement, and vacuum stability testing. Moreover, ProCAST, a finite element casting simulation software, was used to study the temperature field changes and predict the locations of defects generated during the solidification process of melt cast explosives, and the simulated results are consistent with the experimental results. Hence, this work provided a new prospect of micro-and nano-sized TKX-50 particles in castable explosives.

Optimization of Shrinkage Porosity in Grinding Media Balls by Casting Design Modification and Simulation Technique

Shrinkage porosity or cavity are associated with the solidification of the metal either due to gas/air entrapment or when the shrinkage occurring during solidification is not entirely compensated by the riser. Shrinkage cavities occurring in the casting reduces its strength which leads to unfulfillment of the desired serviceability. In this paper, casting design has been modified using the DISA manual to achieve directional solidification which directly relates to improvement of casting quality. The running of metal from pouring basin into casting along with solidification has been analysed through PROCAST which is a casting simulation software based on Finite Element Method and CAFE (Cellular Automata Finite Element) Model. The feeding system of the casting has been modified in terms of shape and volume to minimize air aspiration effect and promote directional solidification. The model used is of grinding media balls casting of high chromium cast iron. The feeding pattern, feeding velocity and solidification with respect to pouring temperature, pouring rate, ambient temperature and film coefficient has been analysed. The final optimum range of all parameters with corresponding minimum shrinkage porosity in casting was obtained. Main aim was to minimize shrinkage porosity in the main casting, ignoring gating and feeding system. The actual minimization of shrinkage porosity comes out around 56 %.

Shrinkage Elimination in Casting of GG30 Grade Cast Iron Impellor by using Pro-cast Software& Finite Elemental Analysis by Meshcast Software

There are 100+ submersible pump manufacturers in Rajkot Engineering Cluster. So, there are 100 plus foundry engaged in casting of cast iron impellor for submersible pump. They face shrinkage defect after casting and about 10 % rejection is because of shrinkage.[1] So in order to reduce this defect casting simulation software is very helpful. By using Pro-Cast simulation software mould of impellor is imported in Pro-Cast software and by applying sand mould condition, pouring temperature, pouring time etc. are put into the software, and finally result shows the areas of impellor where shrinkage chances are more.

Investigation of the Effect of Inoculant and Casting Temperature on Fluidity Properties in the Production of Spheroidal Graphite Cast Iron

Working with liquid metal makes the casting method very advantageous, but also presents some difficulties. One of the common challenges in the casting process is that the liquid metal may not fill the mold cavity completely. This is mainly due to the contact of the liquid metal with the mold surface in the mold cavity, the high heat transfer coefficient of the mold material, and the undercooling and solidification of the liquid metal during liquid movements. For this reason, the fluidity of the liquid metal is important for robust casting production. The fluidity is affected by many factors such as mold properties, casting temperature, and alloying elements. In this study, it is aimed to investigate the fluidity characteristics of GGG60 alloy. For this purpose, the effects of casting temperature, different inoculants, and different inoculant quantities were used in the new mold design, which has different cross-sectional thicknesses. The distance of the alloy in the cavities was also compared with FlowCast Casting simulation software.

Numerical and experimental approach to eliminate defects in al alloy pump- crank case processed through gravity die casting route

A numerical investigation was carried out with the help of computer based casting simulation software to eliminate defects such as shrinkage due to solidification, cracks, imperfect mould cavities and riser level issues. This investigation also helps to improvise the casting process done by gravity method in aluminium based alloys. The defects mentioned above are occurring in the castings due to wrong choice in selecting the process variables or gating and riser design. In this investigation, MAGMASOFT software was used for simulate the casting process undergoing solidification. The results from the simulation shows the possible areas which may be subjected to defects or any other malfunction. Before entertaining the simulation software, few castings were manufactured by making alterations in the process variables and the same castings were modeled and tested using the software. Then, using the MAGMAsoft software, simulations were carried out by modifying the position of the core pins and making possible design changes in the casting component without compromising its design intention. The simulation results showed that, the design changes helped in reducing the casting defects of the centrifugal pump crank case. Based on the simulation result, the castings were produced and checked for the defects. The casting obtained as per the modifications done based on the simulation result showed zero defects.

Effect of Plunger Speed and Solid Fraction on Automotive Component by Thixoforming Simulation

Thixoforming is a promising metal forming process to produce near net-shape components with high casting quality. Thixoforming of metallic alloy utilizes the thixotropic behaviour of the material with near globular or globular microstructure in the semi-solid condition. The solid content is between 50% to 70% before forming. In this paper, the effect of plunger speed and a solid fraction on an alternator housing was investigated by advance casting simulation software. The 3D CAD model of the alternator housing was created using SolidWorks software and AnyCasting software is utilized for the simulation of the thixoforming parameter and magnesium alloy (AZ91D) is the material used. The simulation had been done by varying the plunger speed, temperature (solid fraction) of the material, and both Power Law and Bingham Viscosity model are used in the simulation to identify the defect prediction at the end. The simulation result shows that laminar filling in semi-solid slurry able to achieved by controlling the plunger speed and temperature. Slower speed and lower melt temperatures are preferable in thixoforming. Therefore, a solid fraction of the material, plunger speed, and solidification rate do influence the filling behaviour of the casting of semi-solid metal.