A356 aluminum alloy is widely used in various industries due to its excellent mechanical properties and corrosion resistance. However, during the gravity casting process, it is prone to microscopic defects such as micropores and surface depressions, which significantly affect the quality and performance of castings. This article comprehensively reviews the research on these defects in A356 aluminum alloy gravity casting. It delves into the formation mechanisms of defects, the impact of various factors, and corresponding optimization strategies. By combining experimental research, computer simulation, and data analysis, this study aims to provide a theoretical basis and practical guidance for improving the quality of A356 aluminum alloy castings and promoting the development of the casting industry.
1. Introduction
1.1 Background and Significance of Research
A356 aluminum alloy, with its main alloying elements of silicon and magnesium, has found extensive applications in the automotive, aerospace, and machinery industries. Its low density, good mechanical properties, and excellent corrosion resistance make it an ideal material for manufacturing lightweight components. For example, in the automotive industry, it is used in engine parts, transmission systems, and suspension systems to reduce vehicle weight and improve fuel efficiency. In the aerospace field, it meets the requirements for high – strength and lightweight materials in aircraft components.
However, the wide solidification temperature range and specific solidification characteristics of A356 aluminum alloy lead to the formation of microscopic defects during the casting process. These defects, including micropores and surface depressions, not only reduce the mechanical properties of castings but also limit their application in high – end fields. Therefore, studying these defects is of great theoretical and practical significance. It can help to improve the quality of castings, enhance production efficiency, ensure the quality and structural integrity of products, and promote the implementation of green manufacturing and sustainable development strategies in the casting industry.
1.2 Research Status
Previous studies have made some progress in understanding the solidification process and defect formation in aluminum alloy casting. Scholars have explored the influence of factors such as temperature, riser design, and degassing treatment on casting defects. For example, some research has focused on the relationship between hydrogen content, cooling rate, and micropore formation. However, there are still many challenges. The design of gating systems for complex castings remains difficult, and the interaction of multiple factors on casting defects has not been fully considered. Moreover, although computer simulation has become an important tool for predicting casting defects, there is still a need to further clarify the deviation between simulation and actual situations.
2. Solidification Process of Metal and Analysis Technology of Solidification Defects
2.1 Characteristics of Metal Solidification and Solidification Feeding
2.1.1 Characteristics of Metal Solidification
Metal solidification is the process of transforming from a liquid state to a solid state, during which metal atoms change from a disordered liquid structure to an ordered solid – state lattice, accompanied by the release of latent heat of solidification. The solidification process is influenced by factors such as atomic – level forces, cooling rate, composition, and pressure. There are two main types of solidification: skin – type solidification, which usually occurs in pure metals and alloys with a narrow solidification range, and pasty – type solidification, which is common in alloys with a wide solidification range, such as A356 aluminum alloy.
2.1.2 Solidification Feeding
For A356 aluminum alloy, which is a pasty – type solidifying metal, its solidification feeding process is complex. The main driving force for feeding after the formation of the pasty region is the pressure difference of the unfrozen metal liquid in different stages. According to Campbell’s theory, there are five feeding mechanisms: liquid feeding, mass feeding, interdendritic feeding, burst feeding, and solid feeding. In actual casting, due to the complex shape of castings, some areas may not be properly fed, resulting in the formation of internal pores. Casting shrinkage pores can be divided into external porosity, internal shrinkage, and internal microporosity. The formation of micropores is affected by factors such as environmental pressure, hydrostatic pressure, gas solubility, and shrinkage negative pressure.
| Feeding Mechanism | Description |
|---|---|
| Liquid Feeding | The flow of liquid metal to compensate for shrinkage during solidification |
| Mass Feeding | Mass transfer during solidification to fill voids |
| Interdendritic Feeding | Feeding between dendritic arms |
| Burst Feeding | A sudden feeding mechanism under certain conditions |
| Solid Feeding | Feeding through solid – state movement |
2.2 Shrinkage Negative Pressure
When the solid – phase fraction reaches the critical solid – phase fraction during solidification, the growth of dendritic crystals forms an intertwined three – dimensional network structure. As a result, the subsequent compensatory liquid cannot flow in easily, and the pressure between dendritic crystals drops, generating shrinkage negative pressure. The formula for calculating the liquid pressure between dendritic crystals and its pressure drop has been derived, and a parameter \(V_{S}^{1.62}/G^{0.38}\) has been proposed to predict the pore content in A356 aluminum alloy. When this parameter is less than \(5.7(K^{0.4} ~s^{1.6}/mm^{2})\), the pore content increases with the decrease of the parameter; when it is greater than this value, the pore content is no longer related to the parameter.
2.3 Hydrogen Evolution Problem in Aluminum Alloys
During the solidification of aluminum alloys, the significant difference in hydrogen solubility between the solid and liquid phases leads to hydrogen evolution and the formation of micropores. The number of micropores is related to the hydrogen content. For example, research has shown that the closer to the riser end, the higher the pore content in the casting due to the continuous entry of hydrogen into the unfrozen part. In addition, factors such as cooling rate and the presence of oxide films also affect the formation and distribution of micropores.
2.4 Parameter Criteria
In the past two decades, computer – aided methods have been widely used to predict casting shrinkage defects. Early studies used parameters such as temperature gradient G, solidification rate R, and solid – liquid interface velocity \(V_{s}\) to predict defects. The Niyama Criterion (\(G R^{-1 / 2}\)) is a well – known parameter for predicting shrinkage defects. However, for alloys with a wide solidification range like A356 aluminum alloy, this criterion has limitations. Therefore, new parameter criteria have been developed, such as \(G t_{f}^{2 / 3} v_{s}^{-1}\), which can better predict micropore defects in aluminum alloys.
2.5 Riser Design and Computer – Aided Solidification Analysis
Riser design is crucial for compensating for solidification shrinkage and obtaining sound castings. Traditional riser design often relies on trial – and – error methods and empirical rules. With the development of computer technology, computer – aided solidification analysis has become an important tool. By using simulation software, the solidification process can be simulated, and the formation and location of solidification defects can be predicted accurately. This technology helps to optimize the casting process and improve casting quality.
3. Experimental Methods
3.1 Overall Experimental Scheme
3.1.1 Product Design and Forming Ideas
In this study, three types of A356 aluminum alloy castings (T – type, H – type, and S – type) were designed. The design considered factors such as geometric complexity, material fluidity, solidification characteristics, mechanical properties, and manufacturability. For example, the H – type design has a large cross – section change, the T – type design has a thin wall thickness, and the S – type design contains complex internal angles and turns. These designs are used to study the filling and solidification behavior under different conditions. The flow channel system was designed to control the pouring velocity and reduce defects caused by turbulence. The riser size was determined through solidification simulation software to ensure the integrity of the casting.
3.1.2 Numerical Simulation (Process Simulation)
The computer – aided engineering (CAE) technology was used to simulate the gravity casting process of A356 aluminum alloy. The MAGMAsoft software, widely recognized in the industry, was selected for simulation. This software can simulate the entire process from smelting to casting completion. In the simulation, the flow channel system was designed, and the casting flow velocity was controlled at approximately 0.5 m/s to optimize the casting process.
3.1.3 Product (Defect) Detection
After casting, the solidified castings were taken out. Reverse engineering scanning technology was used to record the casting shape, and the surface shrinkage volume was obtained by comparing with the original mold. Non – destructive X – Ray detection was carried out to identify internal shrinkage pores and evaluate the casting quality. The Archimedes method was used to measure the density of the casting, thereby calculating the porosity and volume to assess the internal quality of the casting.
3.2 Flow Channel System
The flow channel system is designed to control the speed of aluminum liquid and avoid the 卷入 of alumina film. It consists of components such as the pouring cup, sprue, filter, and runner turning point.
3.2.1 Sprue
The design of the sprue was optimized by combining fluid dynamics principles and mathematical modeling. The velocity and cross – sectional area of the metal liquid in the sprue were calculated based on the principles of mass conservation and free – fall motion. The ratio of the cross – sectional area at the top and bottom of the sprue was determined to ensure the smooth flow of the metal liquid.
3.2.2 Foam Filter
Adding a foam filter to the flow channel system can effectively reduce the filling speed of the metal liquid. By comparing the effects of different filter placement methods, the ERTF placement method was selected in this study, which has the lowest flow velocity and the largest flow rate.
3.2.3 Runner Turning Point
To ensure the smooth flow of the metal liquid through the turning point, the fillet at the turning point was designed. The size of the fillet was determined based on the research of Hsu et al. and the specific conditions of this experiment, which helps to reduce turbulence.
3.2.4 Static Pressure Recovery
In the flow channel design, the static pressure recovery method was used to reduce the liquid velocity. The static pressure recovery coefficient \(C_{p}\) was defined to evaluate the effectiveness of static pressure recovery. A double – ingate was set to maintain the flow rate while the velocity decreased.
3.3 Riser System
In this experiment, the riser was designed to study the influence of shrinkage pores on castings with and without risers. The size of the riser was determined by first performing a 2D simulation of the casting without a riser, calculating the area of the external shrinkage pores, and then back – calculating the amount of metal liquid required for compensation. A method combining image acquisition and digital image processing was used to accurately measure the area of the shrinkage region.
3.4 Computer Simulation
3.4.1 Computer – Aided Flow Channel Design
Computer simulation technology was used to assist in the design of the flow channel system and simulate the solidification process of 2D castings. First, a CAE analysis model and a grid model were established. The geometric modeling of the casting was carried out, and the relevant flow channel parameters and riser design were set. The finite – element grid was divided to improve the accuracy of the simulation results.
3.4.2 Simulation of Solidification Shrinkage Phenomena
Before actual casting, the solidification shrinkage of the casting was simulated in 2D to understand the relationship between casting initial temperature, hydrogen content, and shrinkage pores, as well as the simulation accuracy of the software. The critical pressure of hydrogen evolution was set to vary from 0.1 to 1 atmosphere to analyze its impact on the formation of shrinkage pores.
3.5 Experimental Modeling and Degassing Operation
3.5.1 Experimental Modeling
Cold – hardening sand molds with the PUCB (Phenolic – Urethane Cold Box) resin system were selected as the casting molds. The preparation process involved mixing clay – free silica sand with phenolic resin in a ratio of 100:1.8, and then adding urethane to harden the mold to ensure its strength and rigidity.
3.5.2 Degassing Operation
Before casting, the aluminum liquid was degassed. The hydrogen in the aluminum liquid mainly comes from air, crucibles, and casting tools. In the experiment, high – purity argon gas was introduced into the aluminum liquid through a graphite tube and rotated to remove hydrogen. An experimental group without degassing was also set up to observe the influence of hydrogen on micropores.
3.6 Reverse Engineering Scanning and Non – Destructive X – Ray Detection
3.6.1 Reverse Engineering Scanning
Reverse engineering scanning was used to obtain the accurate volume of external shrinkage pores. The Breuckmann opto Top – 530 scanner was used to scan the actual complete original casting. The point data obtained was integrated into the casting appearance using reverse engineering software, and then compared with the volume of the mold drawn by the drawing software to calculate the overall external shrinkage pore volume.
3.6.2 Non – Destructive X – Ray Detection
Non – destructive X – Ray detection (TORECK RIX – 200MC) was carried out to understand the distribution of internal shrinkage pores and determine the position for cutting the casting into a 2D plate – type casting. The working parameters of the X – Ray detection were set, and the results were used to evaluate the casting quality and observe the implementation of the 2D model.
3.7 Measurement of Internal Micropore Content
The Archimedes method was used to measure the internal micropore content of the casting. To ensure the accuracy of the measurement, steps such as non – destructive detection to identify low – density inclusions, sampling from the central part of the casting, grinding the sample surface, and wax – sealing the surface were taken. The density of the sample was measured, and then the porosity and volume of the micropores were calculated.
3.8 Summary of This Chapter
This chapter described in detail the experimental methods used in this study. These methods are designed to comprehensively analyze the formation mechanism of micropores and surface depressions in A356 aluminum alloy gravity casting. The flow channel system, riser system, computer simulation, experimental modeling, degassing operation, reverse engineering scanning, non – destructive X – ray detection, and internal micropore content measurement are all important parts of this experimental system, which provides a reliable basis for subsequent experimental results and analysis.
4. Experimental Results
4.1 Computer Simulation Results
4.1.1 Casting Morphology and External Shrinkage Pore Defects
The simulation results of casting solidification showed that the formation of microscopic defects in A356 aluminum alloy gravity casting is mainly related to the density difference between the solid and liquid phases. In the simulation, the casting morphology after solidification was observed, especially in the riser part, where there was not only a decrease in the end – top surface due to volume reduction but also tubular shrinkage formed by feeding. The external shrinkage pores of different types of castings (H – type, S – type, and T – type) at different pouring temperatures (973K and 1033K) were quantitatively analyzed. The results showed that the H – type casting had a slightly higher shrinkage percentage than the S and T types under the same conditions.
| Pouring Temperature (K) | Type | Original Area (\(mm^{2}\)) | Area of Shrinkage (\(mm^{2}\)) | Percentage of External Shrinkage |
|---|---|---|---|---|
| 973 | H | 8292.57 | 315.85 | 3.81% |
| 973 | T | 8261.92 | 309.18 | 3.74% |
| 973 | S | 8104.86 | 219.6 | 2.71% |
| 1033 | H | 8292.57 | 316.5 | 3.82% |
| 1033 | T | 8261.92 | 307.79 | 3.73% |
| 1033 | S | 8104.86 | 221.55 | 2.73% |
4.1.2 Internal Micropores
The computer simulation predicted the micropore content based on the density difference between the solid and liquid phases. The results showed that the micropore content increased with the increase of the critical evolution pressure. The micropore content of different types of castings at different critical evolution pressures was analyzed, and trend equations were obtained to describe the relationship between them.
4.1.3 Total Shrinkage
The total shrinkage was calculated by adding the content of external shrinkage pores and internal micropores. The results showed that the total shrinkage volume increased with the increase of the critical gas evolution pressure. The total shrinkage of different types of castings at different critical evolution pressures was analyzed, and trend equations were obtained to describe the relationship between them. This data is useful for comprehensively evaluating the shrinkage situation of castings and understanding the interaction between external shrinkage pores and internal micropores.
| Pressure when Gas Form (\(N/m^{2}\)) | Total Shrinkage Volume (\(mm^{2}\)) – H-type – 973K | Total Shrinkage Volume (\(mm^{2}\)) – T-type – 973K | Total Shrinkage Volume (\(mm^{2}\)) – S-type – 973K | Total Shrinkage Volume (\(mm^{2}\)) – H-type – 1033K | Total Shrinkage Volume (\(mm^{2}\)) – T-type – 1033K | Total Shrinkage Volume (\(mm^{2}\)) – S-type – 1033K |
|---|---|---|---|---|---|---|
| 20260 | 441.6 | 449.01 | 350.98 | 440.29 | 449.7 | 352.91 |
| 30390 | 443.48 | 450.89 | 352.84 | 442.17 | 451.58 | 354.65 |
| 40520 | 445.35 | 452.77 | 354.7 | 444.04 | 453.47 | 356.63 |
4.2 Casting Experiment and Detection Results
4.2.1 Non – destructive X – ray Detection
Non – destructive X – ray detection was carried out on the castings. The results showed that there were no macroscopic shrinkage pores in the castings, and the micro – shrinkage pores were mainly concentrated in the central part of the castings. The distribution of micro – shrinkage pores in different types of castings was observed, which provided important information for understanding the internal quality of the castings.
4.2.2 Reverse Engineering Scanning
Reverse engineering scanning was used to measure the external shrinkage pore volume of the castings. The results showed that the surface sink phenomenon could be clearly observed in the castings after solidification. The total shrinkage volume (external shrinkage pore volume) of different types of castings under different pouring temperatures and degassing conditions was measured, and the data was compared to analyze the influence of various factors on the external shrinkage pores.
| Pouring Temperature | Degas | Type | Shrinkage Volume (\(mm^{3}\)) | Shrinkage percentage |
|---|---|---|---|---|
| 973K | YES | H – NR | 673711.62 | 34.88% |
| 973K | YES | T – NR | 106070.84 | 7.86% |
| 973K | YES | S – NR | 685974.04 | 35.13% |
| 1033K | YES | H – NR | 673821.81 | 34.88% |
| 1033K | YES | T – NR | 16620.33 | 1.54% |
| 1033K | YES | S – NR | 802334.04 | 41.09% |
4.2.3 Micropore Measurement
The internal micropore content of the castings was measured using the Archimedes method. The results showed that the internal micropore content of different types of castings under different conditions was different. The internal micropore content of 3D original castings and 2D plate – type castings was measured, and the data was analyzed to explore the factors affecting the internal micropore content.
| Pouring Temperature | Degas | Type | Volume of Micro Porosity (\(mm^{3}\)) | Micro Porosity |
|---|---|---|---|---|
| 973K | YES | T – NR | 16446.46 | 1.32% |
| 973K | YES | H – NR | 15141.14 | 1.20% |
| 973K | YES | S – NR | 18323.17 | 1.45% |
| 1033K | YES | T – NR | 16788.9 | 1.58% |
| 1033K | YES | H – NR | 18518.17 | 1.47% |
| 1033K | YES | S – NR | 20013.88 | 1.74% |
4.3 Summary of This Chapter
This chapter presented the results of computer simulation and casting experiments. The computer simulation results provided a preliminary understanding of the shrinkage pores in the casting process, including the morphology of external shrinkage pores, internal micropores, and total shrinkage. The casting experiment results, including non – destructive X – ray detection, reverse engineering scanning, and micropore measurement, verified the simulation results to a certain extent and provided more accurate data on the actual shrinkage situation of the castings. These results are the basis for further analyzing the relationship between micropores and surface depressions in A356 aluminum alloy gravity casting.
5. Result Analysis and Discussion
5.1 Shrinkage Morphology
5.1.1 External Shrinkage Pores
For castings with risers, there was a significant shrinkage phenomenon at the junction of the riser and the casting, and the upper end of the riser also had obvious concave shrinkage. This was due to the increase of solid – phase fraction and reaching the critical solid – phase fraction with the increase of solidification time. The unfrozen part at the junction was in a relatively high – temperature solid – liquid two – phase region, and the insufficient strength made it vulnerable to external pressure, resulting in external concave shrinkage. For castings without risers, there was a significant concave shrinkage at the front (upper) end of the casting. The morphology of external shrinkage pores was also affected by factors such as gravity and the inclination angle of the casting. For example, in H – type castings with risers, the upper end of the riser was more obviously concave along the gravity direction; in T – type castings with risers, the concave shrinkage on the left side was more serious due to the inclination angle; in S – type castings with risers, the concave shrinkage at the top of the riser was more uniform.
5.1.2 Internal Micropores
In actual castings, the distribution of internal micropores in the thinned castings increased from the cold end (far from the riser end) to the riser end, and the shrinkage pores were more concentrated near the interface between the riser and the casting. In castings without risers, the shrinkage pores were mainly concentrated in the middle part of the casting. Computer simulation results showed that in castings with risers, when the solidification fraction reached the critical solid – phase fraction, the feeding became difficult, and the internal began to generate shrinkage negative pressure, resulting in interdendritic feeding and the formation of micropores. In castings without risers, due to the lack of feeding, macroscopic shrinkage pores were formed inside the casting, and the external concave shrinkage occurred when the solid – phase fraction reached a certain level.
| Casting Type | Micropore Distribution Characteristics |
|---|---|
| Castings with Risers | Micropores mainly concentrated at the junction of the casting and the riser, increasing from the cold end to the riser end |
| Castings without Risers | Micropores mainly concentrated in the middle part of the casting |
5.1.3 Shrinkage Pore Content
Analysis of the shrinkage pore content showed that among the 2D plate – type castings, the H – type castings usually had a relatively high internal micropore content, which was speculated to be related to their long solidification time and wide solid – liquid two – phase co – existence interval. T – type castings without risers had the most external shrinkage pores, because their short solidification time led to a narrow solid – liquid co – existence zone and easy feeding, while the unfrozen external aluminum alloy was affected by gravity, external pressure, and shrinkage negative pressure to form external shrinkage pores. There was a complementary relationship between internal micropores and external shrinkage pores. When the internal micropore content was high, the external shrinkage pore content was usually low, which was related to the offset of shrinkage negative pressure by external shrinkage pores or internal micropores and the casting type. The influence of casting type on shrinkage pores was significant. Different casting types had different gravitational conditions during solidification, resulting in differences in external shrinkage pores. The inclination angle of the casting also had an impact on external shrinkage pores and internal porosity. Generally, the increase of the inclination angle of the casting led to a decrease in internal micropore content, but the S – type casting had a relatively high internal micropore content due to high temperature and non – degassing.
| Influence Factor | Impact on Shrinkage Pores |
|---|---|
| Casting Type | Different types lead to different external shrinkage pores due to different gravitational conditions during solidification |
| Inclination Angle of Casting | Increasing the inclination angle generally reduces internal micropore content, but S – type casting is an exception |
5.2 Computer Simulation of Shrinkage Pore Prediction
5.2.1 Comparison between Actual Casting and Computer Simulation
Comparison between the actual casting and computer simulation in terms of internal micropore content showed that although the trend of the decrease of internal micropore content with the increase of the casting inclination angle was consistent, the reduction range of the simulated internal micropore content was smaller than that of the actual measurement. This was related to the density values set in the computer simulation. The computer simulation was effective in presenting the distribution of internal micropores, but there was a difference in the predicted content compared with the actual measurement.
5.2.2 Total Shrinkage
In terms of total shrinkage, both the actual casting and computer simulation showed a downward trend with the increase of the casting inclination angle. However, there was a gap between the simulation results and the actual values. The external shrinkage in the computer simulation depended on the set solid – phase and liquid – phase densities, and the influence of internal shrinkage pores on the total shrinkage was more significant than that of external shrinkage pores.
| Casting Temperature | Comparison of Total Shrinkage between Simulation and Actual Casting |
|---|---|
| 973K | Both show a downward trend with the increase of the inclination angle, but there is a gap between the values |
| 1033K | Similar to 973K, with a gap between simulation and actual values |
5.3 Summary of This Chapter
This chapter analyzed the relationship between micropores and surface depressions in A356 aluminum alloy gravity casting under different casting initial conditions through computer simulation and actual casting experiments. It was found that the formation of external shrinkage pores was related to solidification time, solid – phase fraction, and critical solid – phase fraction, and was also affected by the inclination angle and gravity. The distribution of internal micropores was related to the presence of risers, and the shrinkage pore content was affected by factors such as casting type and inclination angle. The computer simulation was a useful tool for predicting shrinkage pores, but there were still some differences compared with the actual situation, which needed to be combined with experimental data for more accurate analysis.
6. Conclusions and Outlook
6.1 Conclusions
This study comprehensively analyzed the formation mechanism of micropores and surface depressions in A356 aluminum alloy gravity casting through experimental methods and computer simulation technology. The main conclusions are as follows: (1) The designed flow channel system and controlled pouring velocity effectively reduced defects caused by turbulence, and the riser size was predicted by solidification simulation software. However, the problem of uniform filling of complex castings remains to be further studied. (2) Castings with risers had obvious shrinkage at the junction of the riser and the casting, while castings without risers had obvious concave shrinkage at the front end. These phenomena were related to solidification time, solid – phase fraction, and critical solid – phase fraction, but the quantitative data on the influence of the inclination angle on shrinkage pores was lacking. (3) Internal micropores were mainly concentrated at the junction of the casting and the riser in castings with risers, and widely distributed in the middle part of castings without risers. Riser design played an important role in controlling the formation of internal micropores. (4) The computer simulation was effective in predicting the distribution of internal micropores, but there was a difference in the predicted content compared with the actual measurement, indicating that there was room for improvement in simulation parameters and methods. (5) Casting type and inclination angle had a significant impact on shrinkage pores. The increase of the inclination angle generally led to a decrease in internal micropore content, but the critical value of the inclination angle was not determined. (6) The computer simulation could predict the distribution of internal micropores, but it could not fully present the surface depression phenomenon of aluminum alloys. There was a complementary relationship between internal micropores and external shrinkage pores. The simulation results needed to be calibrated with experimental data.
6.2 Outlook
Although this study has achieved certain results, there are still some limitations. The accuracy of computer simulation in predicting internal micropore content needs to be improved, and the simulation ability for aluminum alloy surface depression is limited. The control and measurement of hydrogen content in the experiment were not accurate enough, and the influence of other environmental factors such as humidity was not clear. The experimental data was relatively small. In view of these limitations, the following prospects are proposed: (1) Further optimize casting parameters, especially the inclination angle and riser design, to achieve more precise process control and improve casting quality. (2) Deepen the research on the formation mechanism of defects such as micropores and surface depressions, especially the change rules under different casting conditions, to provide a more comprehensive theoretical basis. (3) Improve the accuracy and reliability of computer simulation technology, especially in simulating the surface depression phenomenon unique to aluminum alloys. (4) Explore new casting materials and processes to reduce energy consumption and environmental pollution and improve casting performance and production efficiency. (5) Strengthen the training of casting technology talents to improve the skills and innovation ability of engineers and promote the development of casting technology. (6) Strengthen international cooperation and exchanges, introduce foreign advanced technology and management experience, and enhance the status and influence of China’s casting industry in the international community.
