Sand Mold Casting Research Articles

The Making of Roman Lead Ingots. Their Casting by Experiment and the Archaeological Evidence

Casting experiments in Brilon-Hoppecke (North Rhine-Westfalia, Germany) in 2011 and 2012 as well as in 2015 aimed to reconstruct the production of Roman lead ingots with the help of archaeological experiments on the one hand; on the other hand, traces of the moulding process on the Roman lead ingots themselves and the epigraphic evidence were examined to provide further information on the production process. The results of this research, suggest that most of the lead ingots were very likely cast in clay sand moulds which almost completely disintegrated after the ingots had been removed. In a few cases, wood could be verified as the material for the moulds. Finally, all known artefacts associated with the casting of lead ingots have been critically examined and reinterpreted.

Метод поєднання ливарного та термічного процесів виготовлення виливків із залізовуглецевих сплавів

With the help of innovations at an industrial enterprise, it is possible to increase labor efficiency and reduce the resource intensity of production. The relevance of the development of the technology of metal casting in sand molds, as the most common casting process, is justified by the fact that up to 80 % of the tonnage of castings is produced in such molds, including special types of casting in molds from sand materials. 60-70 % of the equipment capacities, areas, and personnel of foundry shops are attributed to molding processes, including mixing and rod production. Pollution "due to the mold" can reach up to 80%. A significant potential for the development of foundry mold technology is the improvement of the processes of casting metal into molds made of loose sand without a binding component, in particular, according to the Lost Foam Casting Process (LFC). The authors present the concept of improving the processes of casting metal into molds made of loose sand by the method of dual application of molding materials and give examples of such application. The use of loose molding sand for rapid cooling of the casting, including heat treatment, is able to strengthen its metal and reduce the duration of cooling of the casting in the mold, which leads to an increase in the productivity of foundries without increasing the number of furnace equipment and loose mold filler. The applied method of isothermal hardening (austempering) from the hot state of castings from iron-carbon alloys excludes heating with exposure for austenization of castings, which reduces the cost, time and energy consumption of obtaining products with a strengthened bainite structure, which, in fact, corresponds to the concept of realizing internal reserves as a foundry sand mold, and cast metal. Some foundry enterprises of the Vinnytsia region also use LFC or have concluded contracts, planning to reconstruct their shops for this ecological and economically beneficial foundry technology.

An inverse estimation of frozen sand mold-melt heat transfer coefficient in the solidification of A356 alloy

Casting aluminum alloys is widely used in aerospace, rail transportation, automotive, ships, and other fields. The frozen sand mold casting (FSMC) technology provides a greener and low-cost solution for the sand mold casting industry, which has a better operating environment than the resin sand mold casting and a higher degree of subcooling for solidification process. The interfacial heat transfer coefficient (IHTC) is a significant parameter that affects the structure and properties of the frozen casting. It is also an important boundary condition in numerical simulation. In this paper, a frozen sand mold casting (FSMC) process thermal conductivity problem (IHCP) inversion model is proposed based on the 1-D heat transfer assumption using a combination of finite difference method (FDM) and conjugate gradient method (CGM). The inversion model is validated for its rationality and accuracy in terms of experiments and numerical calculations, respectively. The IHTC is determined under various frozen sand mold casting conditions, including different initial frozen temperatures, water contents, and molding sand. The accuracy of results is verified by comparing the experimental and numerical data. A new method is provided for determining IHTC in frozen casting.

سباكة الصلب عالي السبائكية AISI321 باستخدام السباكة الرملية

In this work, sand casting was used to obtain high-strength steel AISI-321 by melting alloy AISI304 using sand casting. This is in addition to titanium using an induction furnace, which is considered one of the metal forming processes that originated from the principle of casting in sand molds. In general, Ti will oxidize quickly in the melt if it is exposed to air in typical sand/investment casting processes; Titanium element provides greater resistance to inter granular corrosion. Stainless steel alloy 321, which differs from 304 in that it contains a percentage of titanium, which has given it the property of being used at high temperatures, which has increased the need or demand for stainless steel casting in some industries and due to the difficulty and complexity of producing some pieces or parts using SS304 (wrought) forging alloy by Machines, so that it became necessary to search for a way to improve quality and reduce time and cost, using plumbing technology, although information about this technology is not available in open references. The ability to cast stainless steel is affected by a variety of factors, such as the time and degree of melting, the types of additives, and the time of total solidification. In addition, there are some other casting factors that have a direct impact on the quality of casting stainless steel, such as the sand mold materials, their type, preparation of the sand mold, and the heat treatment steps. This research includes two parts, a theoretical part that includes the steps of sand casting, and the second part related to the practical side, where the effect of some casting factors was studied, which includes the weight and quantity of addition of titanium (300 to 1000 grams), the time of addition and pouring from (3 to 15 minutes), as well as a study of heat treatment and its effect. This is due to the quality of the stainless steel alloy under study. In each experiment, 100 kilograms were used on stainless steel 321 and 304. The practical experiments were completed in several experimental stages, and in each stage, some modifications were made so that they were based on previous results. The results of the chemical analysis of the last five samples showed a gradual increase in the amount of Ti% until it reached about 0.4%. The tensile strength and yield strength were at acceptable values compared to the Wrought SS321 and cast SS (CF) alloys, an austenitic stainless steel, where the lowest value was (200 and 198) MPa and the highest value was (559 and 315) MPa, respectively. The hardness values were between (145 to 149). Key words: sandcasting, Austenitic SS321, SS304, FeTi.

Dual-Alloy Sand Mold Casting: Main Principles and Features

AbstractThe multi-material injector casting (MMIC) process allows the production of castings with two different alloys in a single process. The metal is introduced into the mold through a ceramic down sprue (injector) that moves with the rising surface of the melt. This results in a beneficial temperature distribution in the casting with enhanced filling and feeding properties. Combining two alloys in one casting affects the chemical composition, microstructure, and mechanical properties, which differ from those of the original alloys. The main goal of producing the dual-alloy castings is to adapt the alloy locally in the mixing zone according to the application needs. The original composition and characteristics of both alloys have to be ensured as much as possible. This article discusses the peculiarities of dual-alloy sand mold casting, considering the oxidation processes of the components under different conditions and the microstructure of the resulting ingots. The results of thermodynamic simulation, experimental dual-alloy sand mold casting, chemical composition, and macrostructure of the resulting castings are given in the article. The following factors have been investigated: the method of pouring two alloys (AlSi12 and AlSi9Cu3), which simulate two injector positions; the time between pouring each alloy (60, 90, and 120 s); the influence of a directional solidification with the bottom chill. The mixing zone was identified by the changes in the content of Cu measured by spark spectroscopy and EDS.

Determination of interfacial heat transfer coefficient at the frozen sand mold casting process of ZL101 alloy

Compared to the resin sand mold casting process, frozen casting is more environmentally friendly, providing a better working environment and enhanced supercooling degree. The interfacial heat transfer coefficient (IHTC) between frozen sand mold and metal is an important parameter that significantly influences the final mechanical properties and microstructure of the castings. This paper solved the inverse heat conduction problem using the finite difference method (FDM). In addition, the conjugate gradient method (CGM) was adopted to calculate the temperature distribution and heat flux in the molten metal. At the same time, the particle swarm optimization algorithm (PSO) was used in temperature distribution determination in frozen sand mold. The interfacial heat transfer coefficient (IHTC) was estimated during the solidification of ZL101. The results showed a good agreement between calculated and experimental data, obtaining accurate casting interface temperature Tm, frozen sand mold interface temperature Ts, heat flux q, and IHTC. The analysis of the IHTC variation revealed a water content value within the range of 4 wt.% to 5 wt.% resulted in IHTC in two types of interpretation, called ‘fluctuation type’ and ‘turning type’.

Comparative Studies of Microstructural, Mechanical and Tribological behaviour of A319 alloy cast in solid waste mold and conventional sand Mold

Abstract This study investigates the potential of utilizing industrial solid waste (blast furnace slag, ferrochrome slag, and red mud) as mold materials to improve the solidification rate and wear resistance of A319 alloy. Unlike conventional molds such as silica sand and olivine sand, industrial solid waste poses an eco-friendly alternative, contributing to waste valorization. The motivation for this research drives the need for sustainable and efficient waste management practices in the industrial sector. By exploring the utilization of industrial solid waste as a mold material, study aims to address the current challenges in disposal, reduce environmental impact, and enhance the overall performance of A319 alloy through improved solidification and wear resistance. The experimental phase involved multi-factor reciprocating sliding wear tests conducted on a sample using a linear reciprocating tribometer, employing a steel ball as a counter face. The investigation of reciprocating wear characteristics aimed to assess the correlations between solidification rate and wear properties of a specimen cast in an industrial solid waste mold as well as a sand mold. Notably, tribological test results revealed a low wear rate of 3.3 mg/Km for the blast furnace slag mold. The scanning electron microscopy (SEM) image of the wear surface showed adhesive wear mechanisms. This study contributes valuable insights into the potential environmental and performance advantages of repurposing industrial solid waste for foundry applications.

Application of sand mold casting modelling for casting pump volute

This work details the development of a gating system for sand mold casting utilizing advanced computer technologies in the casting industry. The study employs advanced methods to manufacture a component referred to as the pump volute. Made from the EN-GJN-HV600(XCr23) alloy, this component displays superior technological characteristics, notably for the production of sand mold gravity castings. SolidWorks software is utilized to generate 3D models of the component and the fill system based on predetermined dimensions. Subsequently, the component is imported into Pro-CAST software to conduct a simulation. Various time parameters were inputted during the study. Post-simulation, defects were scrutinized, and the casting system underwent modification to eliminate them. The process was iterated on the software and its efficacy was verified to be faultless.

The effect of cooling plate, mechanical vibration, and grain refinement on the microstructure and hardness of A380 produced by sand mold

ABSTRACT The mechanical properties of aluminium alloys can be increased by controlling the grain size and morphology of the alloy. In these studies, mechanical vibration, cooling slope plate (CSP), and grain refiner were applied on sand mould casting using A380 alloys. The hardness, and microstructure of the cast samples are investigated. These processes lead to the refinement of grain structures and a decrease in the tendency for dendritic structure formation. The Effect of the solidification time (modulus) on the microstructure is investigated. It was determined that the solidification time varies depending on the section thickness, which affects the SDAS values. It was observed that the lowest SDAS values were in CSP and the highest values were in grain refiners added casting. The lowest hardness value was recorded at CSP casting. Meanwhile, the grain refiner added vibration casting exhibits the highest hardness.

Compensated printing and characterization of the droplet on the binder migration pattern during casting sand mold 3D printing

With its unique advantages, binder jetting additive manufacturing technology has shown significant development potential in the additive manufacturing of complex casting sand mold. After droplet deposition, the permeation and migration of the liquid binder in the porous powder bed have a critical impact on the final performance of the printed sand mold. Taking the piezoelectric printhead as the research object, using Furan resin as the liquid binder and silica particles for the powder bed, the effect of binder content on the dimensional accuracy and mechanical properties of the formed sand mold parts was discussed. Several samples were printed with different volumes of droplets, and the droplet diffusion mode, dimensional accuracy, mechanical properties, and formability were measured, respectively. These indicators were quantified based on the different binder saturation, by comprehensively considering the correlation between the indicators. The methods of grayscale printing and layer thickness compensation are given to improve the product quality. The results show that a more extensive liquid saturation produces better strength and formability with the tradeoff of a significant increase in dimension error. However, by independently adjusting the droplet amount of the liquid binder at each printhead, the desired dimension inaccuracy, strength, and formability can be achieved at each precise place. The future application can be implemented in the binder jetting of precision casting sand mold 3D printing to accelerate its industrial development.

Finger millet husk ash Si3N4 as an alternative mold material for green sand mold casting of AA7075 alloys: an optimization study

Finger millet husk ash Si3N4 as an alternative mold material for green sand mold casting of AA7075 alloys: an optimization study

Microstructural and mechanical characteristics of AlSi5Cu3 aluminum alloy cast in metal mold and sand mold

In this effort, the impact of mold material on the microscopic behavior and mechanical performance of AlSi5Cu3 alloy was investigated. The AlSi5Cu3 alloy was cast in the metal and sand molds with equal cavity size and the characteristics of castings were evaluated. The metallographic analysis revealed that, due to the rapid solidification, the number of grains is 2.17% higher and the grain area is 3.71% less compared to sand mold casting. Moreover, due to the formation of more refined grain structures, metal mold casting has greater mechanical properties compared to sand mold casting. The findings revealed that the hardness, ultimate tensile strength (UTS), and impact strength of metal mold casting samples were improved by 8.82%, 10.74%, and 12.5% compared to sand mold casting samples.

RAFFMETAL EN AB-Al Si9Mg (EN AB-43300)

Abstract Raffmetal EN AB-Al Si9Mg (EN AB-43300) is a heat-treatable, aluminum-silicon-magnesium casting alloy in ingot form for remelting. It is used extensively for producing sand and permanent mold castings for applications requiring a combination of excellent casting characteristics, high strength with excellent ductility, and good corrosion resistance. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on casting, heat treating, and machining. Filing Code: Al-500. Producer or source: Raffmetal S.p.A.

Simplified Model Predicts Binder Behavior in Sand Mold Printing

Binder jetting is a crucial process in additive manufacturing (AM) and is widely used in sand mold casting. This study explores the challenges of simulating binder droplets in ANSYS Fluent, including complexity and computational time. To overcome these challenges, we propose a geometric approach that models the binder droplet as a circular shape instead of an actual droplet. Additionally, the dynamic mesh feature is employed to transform the initial boundary condition into a wall condition at a specified time interval (Δt). This simplified approach eliminates the need to simulate actual droplets, leading to significant computational resource and time savings. By adopting this geometric approach, we can accurately predict the diffusion and penetration behavior of binder droplets with varying materials and volumes in porous media with different porosities. Through data analysis, it was found that the main variables affecting the diffusion diameter and penetration depth are binder volume and porosity. The successful implementation of this simplified model enables researchers and engineers to expedite the simulation of binder behavior, facilitating process optimization and enhancing the understanding of binder jetting technology in the field of additive manufacturing.

RIO TINTO A356.2

Abstract Rio Tinto A356.2 is a heat-treatable, aluminum-silicon-magnesium casting alloy (3xx.x series) that is available in the ingot form for remelting. It is used extensively for producing general-purpose sand and permanent mold castings that require a combination of medium strength with good elongation, very good corrosion resistance, and excellent casting characteristics. Alloy A356.0, which is a higher purity, low iron version of alloy 356.0, provides better elongation and somewhat higher tensile strength. Alloy A356.0 is used in premium, higher strength applications and is used extensively in safety critical applications. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength. It also includes information on corrosion resistance as well as casting, heat treating, and machining. Filing Code: Al-499. Producer or source: Rio Tinto Limited.

RIO TINTO 356.2

Abstract Rio Tinto 356.2 is a heat-treatable aluminum-silicon-magnesium casting alloy (3xx.x series) that is available in the ingot form for remelting. It is used extensively for producing general purpose sand and permanent mold castings that require a combination of medium strength, very good corrosion resistance, and excellent casting characteristics. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fatigue. It also includes information on corrosion resistance as well as casting, heat treating, and machining. Filing Code: Al-498. Producer or source: Rio Tinto Limited.

Numerical Research on the Effects of Process Parameters on Microdroplet Jetting Characteristics by Piezoelectric Printhead

The precision and consistency of the microdroplet jetting procedure are crucial for the casting sand mold’s performance during binder injection. The generation and jetting of microdroplets in piezoelectric printheads were examined in this study in relation to changes in specific jetting process parameters. Using finite element analysis and a simplified physical model of a microdroplet jetting device, an electromechanically coupled model of a microdroplet jetting device was created in order to study the characteristics of microdroplet jetting. A volume-of-fluid model was also created in order to study the microdroplet jetting process and perform repeatability tests. The effects of altering nozzle radius, actuation pulse width, intake velocity, and fluid viscosity on microdroplet jetting properties were then investigated using the models. We were able to control the development of satellite droplets thanks to the knowledge we gained about how each process parameter affected droplet status. This study demonstrates how the radius of the nozzle and the pulse width of the piezoelectric actuation signal have a significant impact on the jetting properties of piezoelectric printheads and the production of microdroplets. The quantitative correlations between process factors and jetting characteristics can be used to optimize microdroplet production and reduce droplet size. Finally, this study will help create control systems for microdroplet jetting operations and enhance the precision of 3D printed casting sand molds.

Research on look ahead control of contour error for casting sand mold with five-axis linkage high speed machining

Casting sand mold with five-axis linkage high speed machining has the characteristics of high feeding speed, small milling force, fast tool axis swing speed and big contour error. The coupling relationships among tool axis swing, following error and contour error were analyzed, the computing method of axis movement speed for five-axis linkage machining was proposed, and a rapid linear estimation model of contour error for casting sand mold with five-axis linkage machining was established. On this basis, according to the relationships between rotary axis speed and tool axis swing speed, a look ahead self-adaptive control method of contour error for casting sand mold with five-axis linkage high speed machining was proposed, and an experiment of impeller sand mold with five-axis linkage machining was carried out. The results show that the contour error formed by tool tip can be estimated rapidly according to the tool axis swing speed in the process of casting sand mold with five-axis linkage high speed machining, and the proposed look ahead control of the rotary axis speed is an effective method for contour precision of casting sand mold with five-axis linkage high speed machining.

Performance Evaluation of Austempered Ductile Iron Camshaft Low Alloyed with Vanadium on an Electric Spin Rig Test

Arbomex S.A. de C. V. is one of the largest worldwide manufacturers of ductile cast iron camshafts, produced by means of the phenolic urethane no-bake sand mold casting method and cold box by stack molding technology. As a result of the development of high-strength ADIs, low alloyed with vanadium, for camshaft manufacturing, previous results were published on the as-cast process and the austempering heat treatments applied to the camshafts. In the present work, camshafts of ADIs, low alloyed with 0.2 and 0.3 wt.% V, were produced at austempering temperatures of 265 and 305 °C. The performance of the new camshafts was evaluated by wear testing to ensure the function and durability of the camshafts by means of the block-on-ring wear test and a valve train system to evaluate the volume loss of material removed and the geometrical changes of the camshaft, respectively. The ADIs heat treated to 265 °C showed a microstructure constituted of fine ausferrite that aided in obtaining the highest wear resistance in the block-on ring wear test. No wear or pitting evidence was detected on the camshaft lobes and roller surfaces after the OEM test protocol during the electric spin ring test at low and high conditions for the ADI alloyed with 0.2 wt.% V heat treated at 265 °C.

Search procedure for optimal design and technological solutions to ensure dimensional and geometric accuracy of castings

The object of research in the work is the technology of manufacturing shaped castings in disposable sand molds. The existing problem is that the imperfection of design and technological solutions at the stage of developing the technology of a single sand mold casting leads to deviations in the dimensions and geometry of the castings after their manufacture from the requirements of technological documentation. This can lead to an irreparable shortage of casting. To develop measures to eliminate or minimize the event, which consists in the formation of a shortage of castings in terms of dimensional and geometric accuracy, a procedure for searching for optimal design and technological solutions is proposed. A hypothesis has been put forward that a significant factor that leads to deviations in the dimensional and geometric accuracy of castings from the requirements of technological documentation is the imperfection of the gating system design. It is demonstrated on specific castings how this factor can influence the formation of uneven wall thickness. The proposed procedure, which includes 10 consecutive steps, allows to build a plan for a complete factorial experiment and obtain a regression equation for it, linking the parameters of the gating system with indicators of dimensional and geometric accuracy. The presence of such equations provides the possibility of further experimental optimization and determination of design and technological solutions for the development or improvement of casting systems that minimize the deviations of the dimensional and geometric accuracy of castings from the requirements of technological documentation. This also minimizes the likelihood of an event consisting in the formation of an irreparable shortage of castings. The presented study will be useful for machine-building enterprises that have foundries in their structure, where shaped castings are made in disposable sand molds.