Quality Of Castings Research Articles

Empirical Exploration of Optimal Gating System Design for Sand Casting Process

Purpose: This paper aims to analyse and optimise the gating system used in the sand casting process to produce drainage doors at Deepshikha Casting in Nagpur. It focuses on understanding how gate design impacts productivity and the quality of the cast, drawing attention to common defects and the role of gravity casting techniques. Design/Methodology/Approach: This paper discusses the present gating system of Deepshikha Casting in detail to identify defects, such as sand inclusions, blow holes, pinholes, gas holes, shrinkage, and misruns. The present gating ratio and system weight assessment are thus used to suggest changes in the design to improve the process efficiency and quality of the product. Findings: The research indicates that the existing gating system has an inappropriate gating ratio, resulting in a high rate of faults and reduced productivity. The system also weighs a lot, which deters efficiency. Improving the gating design reduces flaws, increases the quality of castings, and enhances molten metal flow. Research Limitation: The output of the present work is limited to Deepshikha Casting alone, which is used for drainage door casting. Further research must be conducted on different casting products and technologies for a broad application. Practical Implication: This sector of sand casting can benefit from optimising the gating system, maximising productivity and minimising casting defects, thus reducing costs and improving efficiency. Social Implication: The environment will also benefit from efficient casting because of reduced use of resources, reduced waste, and fewer consumables. Better procedures also translate to increased production of safer products. Originality/Value: This paper provides practical, applied solutions for optimising the gating system of sand casting. Its insights are particularly informative for a foundry working with fragile metals and using gravity casting.

An Initial Study of Ultra High Performance Concrete as Reusable Mold Material for Aluminum Casting.

The initial investigation evaluates the feasibility of ultra high performance concrete (UHPC) as a material for reusable molds in aluminum casting. Two specific UHPC formulations were investigated: one based on ordinary Portland cement (OPC) and another utilizing alkali-activated materials (AAM). The study focused on investigating the surface through roughness measurements and the thermal durability through repeated casting cycles. The thermal stability of the molds was investigated by thermogravimetric analysis, mercury intrusion porosimetry, crack segmentation, optical microscopy, and electron microscopy. Results indicate that molds fabricated from AAM-UHPC exhibit relatively better performance in terms of maintaining structural integrity and surface quality over repeated uses. AAM-UHPC molds were able to withstand up to ten casting cycles with acceptable surface degradation and no significant failure, while OPC-UHPC molds exhibited a faster degradation under similar conditions. Microstructural changes and the interaction of UHPC materials with molten aluminum were investigated, highlighting the low adhesion and defect formation. Additionally, the molds demonstrated sound casting quality, with a grain size comparable to that achieved using traditional steel molds (~ 90 µm), underscoring the potential of UHPC materials for enhancing casting quality and efficiency. The study concludes that UHPC, particularly with alkali-activated formulations, shows promise for low-pressure casting environments.

Investigation of Mo microalloying-induced intragranular ferrite and grain refinement

In this work, the Mo microalloying-induced intragranular ferrite and grain refinement are studied through macroscopic experimental research and microstructural simulation. The microstructure and precipitates in high-strength low-alloy steel (DH36 steel) were characterised by an optical microscope and transmission electron microscope to investigate the effect of Mo on fine crystal strengthening and intragranular ferrite induction. It is demonstrated through first-principle calculations that the surface energy of the MoC(100) plane is the lowest and the structural stability is the best, and molecular dynamic simulations confirmed that the phenomena observed in TEM experiments: the α-Fe (100) surface is the optimal orientation surface of the MoC(100) surface. The solidification structure of DH36 steel during the continuous casting process was simulated based on the cellular automaton-finite element (CAFE) model. Based on these observations, solidification structure simulations confirmed the phenomena observed in metallographic experiments. Meanwhile, it is proposed that the grain refinement and microstructure optimisation effect can be controlled by Mo microalloy content, so as to provide important theoretical data for practical shipbuilding steel DH36 production and improvement of the continuous casting quality.

Benchmarking Values of Modulus of Rupture for Shells Used in Different Investment Casting Segments

Modulus of Rupture (MoR) is considered to be one of the most crucial properties of ceramic shells used in manufacturing investment castings. An industrial survey was conducted to get an insight into the availability of such facilities to measure this property even after guidelines about measurement as well as its relevance are very well established. However, benchmarking values of MoR especially for various segments including aerospace, automobile as well as chemical where investment castings are widely employed are not clearly traceable in the literature. The proposed research is mainly focused on the development of MoR testing machine as per established specific guidelines followed by benchmarking values of MoR for specific sectors mentioned above as these sectors use as much as 60% of total investment casting produced in India. Tested samples were specifically prepared to replicate the conditions that are followed in making of shells and samples were tested using a developed MoR machine. It was observed that values of MoR need to be 4.15–4.90 MPa for automobiles; 3.14–4.48 MPa for chemicals and 1.54–2.76 MPa for aerospace to avoid any unwanted effects of MoR on the quality of investment castings used in these segments.

Prediction of the Stability of the Casting Process by the HPDC Method on the Basis of Knowledge Obtained by Data Mining Techniques.

High-pressure die casting (HPDC) of aluminum alloys is one of the most efficient manufacturing methods, offering high repeatability and the ability to produce highly complex castings. The cast parts are characterized by good surface quality, high dimensional accuracy, and high tensile strength. Continuous technological advancements are driving the increase in part complexity and quality requirements. Numerous parameters impact the quality of a casting in the HPDC process. The most commonly controlled parameters include plunger velocity in the first and second phases, switching point, and intensification pressure. However, a key question arises: is there a parameter that can predict casting quality? This article presents an exploratory analysis of data recorded in a modern HPDC casting machine, focusing on the thickness of the biscuit. The biscuit is the first component of the casting runner system, with a diameter equivalent to that of the injection chamber and a height linked to various processes and mold characteristics. While its diameter is fixed, the thickness varies. The nominal thickness value and tolerances are defined by the process designer based on calculations. Although the thickness of the biscuit does not affect the casting geometry, it influences porosity and cold-shot formation. This study aimed to determine the relationship between biscuit thickness and casting quality parameters, such as porosity. For this purpose, a series of injections was produced using automated gating, and biscuit thicknesses were examined. This article presents quality assessment tools and statistical analyses demonstrating a strong correlation between biscuit thickness and casting quality. The knowledge gained from the methodology and analyses developed in this study can be applied in support systems for the quality diagnostics of HPDC castings.

Data-driven optimization of material composition and casting processes for large ferritic nodular cast iron components in wind turbines

Abstract This study addresses the challenges of producing large-scale wind turbine components by proposing an optimization scheme for the material properties and casting processes of ductile cast iron. The study integrates experimental data with JMatPro calculations to establish a comprehensive database of 1, 139 ferritic nodular cast iron samples. Using machine learning and multi-objective optimization, an optimized composition was developed, and Pareto front solutions were achieved with performance significantly surpassing QT400-18. The AI-CAST platform was then applied to refine the casting process for a 6 MW wind turbine hub, reducing internal defects to 2, 738.52 mm³ and decreasing loose defects by 83.68%. This integrated approach not only enhances material performance and casting quality but also offers significant cost savings, suggesting broad applicability for improved production efficiency in the casting industry.

Effect of Mold Electromagnetic Stirring Position on Flow Field and Solidification Behavior of Four‐Hole Nozzle Arc Continuous Casting Large Round Bloom

For the special casting environment of large round bloom mold with four‐hole nozzle, the reasonable choice of mold electromagnetic stirring (M‐EMS) location is of great significance to the quality control of bloom. In this study, the four‐hole nozzle arc continuous casting of φ600 mm‐large round bloom is taken as an example, a 3D mathematical model of liquid steel flow is built, and the solidification and heat transfer under M‐EMS is established. The optimum M‐EMS position was obtained as Z = 600 mm, which is enhanced flow rates, shell uniformity, and brittle interval width, and offers valuable insights for improving casting quality.

Assessing Environmental Contamination through Pollen Analysis of Solitary Cavity-nesting Resin Bees Around Kolhapur City

This study examines how pollen-nectar mixtures collected by solitary cavity-nesting resin bees can serve as bioindicators of environmental pollution. Researchers utilized paper straw trap nests across various locations, including agricultural (Shirgaon to Kandalgaon road in Gokul Shirgaon, Kolhapur), industrial (MIDC Shiroli, Kolhapur), urban (Dabolkar Corner, Kolhapur City), and a control area (KIT's College of Engineering, Gokul Shirgaon, Kolhapur). The nests, installed in February 2024, contained empty straws and some partially packed with larvae from the control area. These nests were designed to mimic natural habitats, allowing mature bees to build nests and create pollen-nectar mixtures for their offspring. Analysis aimed to detect environmental contaminants in these mixtures. Only one sample from the industrial area (Trap Nest Location 5 at Quality Castings, MIDC Shiroli) was recovered, showing elevated levels of iron, manganese, chromium, and nickel, consistent with industrial emissions. In contrast, the control area produced viable samples with detectable levels of magnesium, zinc, iron, aluminum, and barium. The absence of samples from urban and agricultural areas suggests adverse conditions affecting bee populations. This underscores the sensitivity of resin bees to pollution and highlights their role as bioindicators. The study emphasizes the need for effective environmental management to enhance habitat quality and protect both bees and human health.

Improving compositional homogeneity of CF53 steel products by modifying their solidification structure and F-EMS intensity

In this article, based on the mechanism of stirring induced solute washing, the solidification characteristics of CF53 steel for camshafts were systematically studied through industrial casting tests and numerical simulations, focusing on the impact of solidification structure and final electromagnetic stirring (F-EMS) on solute distribution homogeneity in the core area of the bloom casting. The results indicate that excessive columnar crystal development, coupled with inappropriate use of F-EMS, can lead to significant negative segregation in the bloom, resulting in the formation of “white bands” in the following rolling bar products. Compared with weak stirring, strong stirring can affect solutes at deeper levels between dendrites. By reducing superheat and casting speed, expanding the equiaxed crystal zone in the bloom's centre, and carefully controlling the stirring intensity of F-EMS to position the molten steel washing in the equiaxed crystal zone, along with maintaining a maximum tangential velocity of 0.0041 m/s, a substantial improvement in solute distribution homogeneity within the bloom's core area was achieved. The carbon range can be reduced from 0.093% to 0.032%. These findings offer a theoretical foundation and practical suggestions for enhancing the quality of CF53 steel bloom castings and their hot-rolled bar products used in camshaft manufacture.

Use of cast index and three-point index in paediatric both bone forearm fractures: a prospective study

Introduction The majority of paediatric both bone forearm fractures are treated with manipulative reductions and casting; loss of reduction is one of the most commonly reported complications. We aimed to assess the role of cast index and 3-point index as predictor of outcome of a successful closed reduction in distal both bones forearm fractures.Materials and methods This prospective observational study was conducted at the Department of Orthopedics, Kalpana Chawala Government Medical College in Karnal to assess the role of cast index and 3-point index as predictor of outcome of a successful closed reduction in distal both bones forearm fractures. In the present study, 55 patients 16 years old were included irrespective of sex with distal both bones forearm fractures, managed by closed reduction and casting were included.Results Fracture reduction failure was observed in 32.7 % of the patients. Both three-point index and cast index were found to be significantly higher in patients with reduction failure. It was observed that at 2 weeks Area under curve (ROC Curve) for Cast index and Three point index was 0.72 and 0.85 respectively. At 4 weeks, Area under curve for Cast index and Three point index was 0.77 and 0.84 respectively and at 6 weeks 0.74 and 0.86 respectively. Thus, in the present study, CI and 3PI had similar predictability for fracture reduction failure.Discussion There are a few limitations of our study: We could not observe the patients for a longer period of time to know re-modelling in the long term. We did not take in to consideration the severity of fracture, type of anesthesia used (conscious sedation versus General Anesthesia) and the fracture configuration while assessing the outcomes. We also did not collect information about anthropometric parameters like child weight and diameter of the forearm.Conclusion The three-point index and cast index are clinically useful tools to assess the quality of cast molding following closed reduction of pediatric forearm fractures and to predict re-displacement in distal forearm fractures.

Surface defect detection method of aluminium alloy castings based on data enhancement and CRT‐DETR

AbstractThe surface quality of aluminium alloy castings is crucial to quality control. Aiming to address the challenges of limited samples and extensive computation in deep learning‐based surface defect detection for aluminium alloy castings, this paper proposes a surface defect detection method based on data enhancement and the Casting Real‐Time DEtection TRansformer. First, to tackle the issue of small sample sizes and uneven distribution in surface defect data sets of aluminium alloy castings, ECA‐MetaAconC Deep Convolution Generative Adversarial Networks is proposed for generating defects with fewer samples and employ the image augmentation (IMGAUG) library for sample enhancement. Second, building upon the Real‐Time DEtection TRansformer (RT‐DETR), a lightweight partial‐rep convolution is designed to decrease the network's parameter count. Simultaneously, the Deformable attention module and the DRBC3 module are introduced to enhance the neck network, thereby improving the model's capability to capture information and enhancing its detection performance. Compared to RT‐DETR, this method reduces the number of model parameters by 38.7%, increases mAP by 1.5%, and achieves a frame rate that is 1.58 times higher than the original model. The experimental results demonstrate that this method can effectively and accurately detect surface defects in aluminium alloy castings, satisfying industrial requirements.

Control and optimization of defects in die casting of complicated right crankcase cover

The die-casting process of ADC12 aluminum alloy right crankcase cover was simulated based on AnyCasting software, and the influence of pouring temperature, initial mold temperature and injection speed on the filling and solidification process of ADC12 right crankcase cover casting was explored by orthogonal experiment method. The optimal process parameters were obtained through optimization, and the die-casting mold was designed. The program was verified in production. The results show that the porosity and shrinkage of the right crankcase cover are mainly concentrated in the thick wall part. The sequence of process parameters that affect the residual melt modulus is pouring temperature, initial mold temperature, and injection speed; The best combination of process parameters: pouring temperature is ∼680 °C, initial mold temperature is ∼200 °C, injection speed is ∼5 m/s. By analyzing the filling process and temperature field simulation results, the casting structure, mold structure and cooling system were optimized, and the process plan was improved. The production verification was carried out according to the optimized process plan. The casting quality is good and has no obvious defects, which meets the actual production needs.

Worldwide Research Trend on Steel Casting: A Visualization and Future Research Directions

Aims: In this study, we conducted a bibliometric study about steel casting between the year 2000-2023. We carried out a bibliometric analysis of sand casting, investment casting, die casting, and squeeze casting in which optimization and simulation models are available and have been thoroughly developed to enhance the quality of the casting product, according to the keyword co-occurrence network and word cloud generated by the bibliometric analysis and text mining of the publications. Methods: By delving further into the optimisation and simulation models, this study finds multiple casting procedures with various process parameters that have a major effect on the process results. Defects of the mechanical kind are the most prevalent, and factors taken into consideration are emissions, yield, dimensional tolerances, and qualities. Results: The necessity for data-driven modelling in new casting environments has been identified in this study, which will allow for a dynamic casting process and fine-tuning and aid in attaining desirable results in today's competitive markets. In order to illustrate the future prospects of this sector, this research focuses on potential technical interventions in steel casting processes that could enhance the efficiency of the process and the quality of the products produced by steel casting. Conclusion: This study examines the body of literature on various researchers' contributions to the production of excellent casting components and performs a bibliometric examination of the publications. However, the literature study examines research publications from high-quality essential sources to determine the essential criteria influencing steel casting quality.

Nanotechnology enabled casting of aluminum alloy 7075 turbines

Aluminum alloy 7075 is well-known for its high-performance structural systems due to its lightweight and excellent mechanical properties. However, its susceptibility to hot cracking and limited fluidity hinder its casting suitability, posing challenges in manufacturing near-net-shaped structures economically, especially for thin and intricate aerospace components. This paper presents experimental results based on nano-treating, an emerging nanotechnology-enabled manufacturing method by incorporating a low fraction of nanoparticles in liquid aluminum, to allow the casting of complex aluminum alloy 7075 parts. Vacuum fluidity tests demonstrated that nano-treating of aluminum alloy 7075 with only 0.5 vol% TiC nanoparticles increased the fluidity of aluminum alloy 7075 by more than 20%, effectively eliminating hot cracking and enhancing surface quality. Through the Rapid Investment Casting process, nano-treated aluminum alloy 7075 can be successfully cast into turbines with 0.5 mm thick blades. In contrast, aluminum alloy 7075 without nano-treating failed to produce good casting quality due to poor filling and severe cracks. The manufacturing trials highlight the significant improvement in castability achieved through nano-treating, opening a novel pathway for the cost-effective production of complex aluminum alloy 7075 structures for numerous applications.

DESIGN AND ANALYSIS OF THE GATING AND RISERING SYSTEM FOR STEEL SAND CASTING

Steel sand casting involves complex processes that significantly impact the quality and integrity of the final product. Among these processes, the design of the gating and risering systems plays a crucial role in ensuring defect-free castings. This research focuses on optimizing the gating and risering system design for steel sand casting with the aim of improving casting quality and minimizing defects. Through a detailed case study, the study seeks to develop a robust gating and risering system specifically tailored for steel casting applications. Computational applications using CATIA software for 3D modelling and Altair Inspire Cast for process simulation and analysis was employed to rigorously evaluate and validate the effectiveness of the proposed design. The study aims to meet performance criteria and enhance casting integrity. The ultimate goal is to propose an optimal gating and risering system configuration that not only addresses the challenges identified in the case study but also serves as a practical guideline for improving the overall efficiency and quality of steel casting processes. Key findings from the study highlight velocity, solid fraction, and porosity as significant parameters during the filling and solidification process, providing benchmarks for improving the casting process. Ultimately, an improved model with a yield improvement of 17.65% and an enhanced casting process was achieved. The findings underscore the importance of an optimized gating and risering system in enhancing the casting process, reducing defects, and producing high-quality steel products through detailed filling and solidification analysis, ultimately improving casting yield.

Surface and finishing quality exploration of complex cast glass forms produced on disposable moulds

Glass casting displays great forming potential allowing for the realisation of three-dimensional glass elements of virtually any shape and size, as showcased in glass art. Disposable mould technology seems to be ideal for the fabrication of such customised and complex geometries, including for architectural and structural cast glass components deriving from structural topology optimization, since it offers great shape freedom and cost effectiveness. However, currently, glass casting on disposable moulds faces the major drawback of a resulting rough and opaque glass surface quality, requiring considerable post-processing to yield a glossy, smooth surface. This in turn results in a compromised dimensional accuracy and on increased time and production costs. If the surface remains unprocessed, it can greatly affect not only the visual but also the mechanical properties of the cast glass element. Aim of this research is to improve the surface quality of complex glass components cast in disposable moulds, directly during demoulding, reducing in this way the need for post-processing. To achieve this the research focuses on exploring ways to pre-process disposable moulds. In specific, the research focuses on series of kiln-cast laboratory experiments at various maximum firing temperatures / annealing schedules involving the use of two different types of disposable moulds, 3D-printed sand moulds and silica plaster moulds (Crystalcast®), and the application of refractory coatings, coating combinations and protective layers. The experimental work conducted thus far indicates that the best results are obtained at the lowest maximum temperature tested (870 °C), with the combination offering the best finishing quality to be a synthetic (ceramic) sand mould coated with Crystalcast® and Zirkofluid® (6672, 1219). Scaling-up of the kiln-cast prototypes unveils a complex correlation between the maximum dwell time at the maximum firing temperature and the casting effectivity/ performance of mould materials and coatings.

Experimental investigation and fluid-structure interaction modelling of the casting of self-compacting concrete for CRTS III slab track in the curved segments

Ensuring the casting quality of self-compacting concrete (SCC) is crucial for the operational safety and durability of China railway track system (CRTS) III slab track. However, the mechanisms of key factors influencing flow behaviors of SCC and structural responses remain insufficiently understood, nor is the relationship between flow behaviors and structural responses during casting. In this study, fluid-structure interaction (FSI) models of SCC casting were developed and verified by full-scale physical tests, comprising slump flow, L-box flow and casting of SCC in an actual track at the field of Laixi-Rongcheng high-speed railway. Through in-depth analysis on the casting process of SCC in curved segments with a super elevation of 80 mm, the relationship between flow behaviors and structural responses was established. Furthermore, the influence mechanisms of key factors on flow behaviors and structural responses were investigated systematically. Results show that during gravity-fed SCC casting, its flow velocity diminishes, thus increasing the static pressure and the forces exerted on the slab by SCC. These vertical and lateral forces increase to 147.16 and 7.83 kN through three stages of development, acceleration and stabilization, resulting in commensurate structural responses. At the end of casting process, the central region of the slab exhibits maximum vertical deformation of 0.95 mm and tensile stress of 1.07 MPa. The tension rods at the side with lower elevation bear greater vertical and lateral forces than the ones at the side with higher elevation. The rise of funnel height from 1.05 to 1.35 m accelerates the casting process but increases the forces exerted by SCC by up to 26 % and augments the associated response of entire structures, whereas the funnel diameter shows little effect. Increasing yield stress of SCC from 9.3 to 49.3 Pa produces a more uniform flow morphology and thus higher static pressure and force by SCC in the middle region of the slab, impacting the structural responses by up to 15 %. The growth of plastic viscosity from 59 to 99 Pa⋅s significantly affects the volume rate and casting time by up to 66 % but has little effect on the flow morphology, fluid pressure and structural responses. In order to ensure high quality casting of SCC, five clamping beams are suggested with two beams positioned at either side of the slab and the other three evenly placed along the middle region of the slab.

Comparison and evaluation of the cast iron castings surface using different types of foundries sands

This study investigates and compared various properties of high-quality foundry sands on the surface quality of castings, whose cores are produced using the col-box method. Methods such as the measurement of flushable fraction, sieve analysis, electron and optical microscopy, pH and electrical conductivity measurements were used to monitor the physico-chemical properties of silica and non-silica sands. 5 core mixtures were prepared from individual sands by adding 1.6 % of organic binder based on phenol-formaldehyde formed from resin and hardener using an MR100 mixer. The produced cores were placed in moulds made of a uniform bentonite mixture and cast (15 test castings). In all the tested sand samples, the dust content was visible at a 300× magnification, but the share of flushable content is not exceeded 3 %, which is one of the fundamental conditions for moulding. All the tested sands are heat resistant at 1600 °C and had a low flushable fraction in the range 0.05–0.3 %. The results indicate that the occurrence of surface defects in high-quality foundry sands is not related to the flushable fraction content, to the average grain size value d50, to the electrical conductivity, to the shape of the sand grains and to the flexural strength. The surface roughness is related to the average grain size, to the grain shape and to the flexural strength.

Experimental study on construction quality control standards of rubber granule-fluidized fly ash roadbed fillers

As a new type of roadbed filler, the lack of construction quality control standards for rubber particles-fluid fly ash will limit its large-scale popularization and application. In this paper, the key factors affecting the quality of filler casting were selected through indoor tests, and the research on the construction quality control standard of rubber granule-fluid fly ash roadbed filler was carried out to get the optimal construction parameters of filler, and the sensitivity of each parameter was analyzed to make clear the order of the significance of the different construction factors affecting the compressive strength of filler. The results show that: the more the number of layered layers, the shorter the pouring interval, the longer the mixing time, the faster the mixing speed, the smaller the pouring angle, the shorter the soaking time, the greater the strength of the casting body. Too high or too low temperature will reduce the strength of the casting body, and the strength of the casting body is maximum when casting at 20℃. The specimens with different pouring thicknesses showed the strength distribution pattern of large strength in the upper and lower parts and small strength in the middle. Sensitivity analysis showed that the factors affecting the strength of the casting body in the order of significance were casting temperature, casting interval time, casting humidity, casting angle, mixing time and number of layered layers.

Flexural strengthening of RC beams using external unbonded rebar: an experimental investigation

ABSTRACT Flexural strengthening of reinforced concrete (RC) beams is an important research topic due to its huge practical demand. In the present study, a new flexural strengthening method for RC beams, called the Shear-key Mounted Unbonded Rebar (SMUR) technique, is proposed and its effectiveness is examined through an experimental investigation. A total of 12 RC beams were cast and tested under four-point loading. Ten were strengthened and the remaining two the original or control beams. Before casting the RC beams, their constituent materials, such as cement, aggregate and rebar, were tested to ensure the quality of casting. The beams were strengthened with unbonded rebars attached to their tension faces through shear keys. One of the main advantages of the proposed technique was its speed and ease of application. As well as its effectiveness, the effects of other important aspects, such as the size and location of the rebar, were also examined. It was found that the proposed method noticeably enhanced the flexural capacity of a control beam. The ultimate load capacity of a strengthened beam was 60% higher than that of a control one. The flexural performances of the beams could be further improved by increasing the bar size and its location. The welding and conventional flexure were the dominant modes of failure in the strengthened beams.