# Application of Foundry Wastes in Eco-Efficient Construction Materials: A Review
## 4 Evolution of Research on Foundry Waste: Bibliometric Analysis  
A bibliometric analysis was conducted to show the interest of the scientific community in this topic and to understand the trends. The research in the database was conducted using the topic \"foundry waste\" in the Web of Science database. From the first publications until 2023, there has been a significant increase in the number of published articles. Considering the period between 1986 and 2023, the number of published articles increased by 4400%. In the last 10 years, the increase was approximately 182%, which is also a remarkable growth. The analysis reveals a growing interest in the topic of foundry waste (Figure 5). This trend indicates that the topic has gained popularity in academic and research fields, possibly due to growing environmental concerns and the need for sustainable waste management strategies in the foundry industry, with greater emphasis in recent years resulting from the strategies adopted by the European Union. Another analysis relates the number of publications to the countries involved. There are publications on the topic of \"foundry waste\" in 74 countries. The 10 countries with the highest number of publications in this area are represented in Figure 6. It can be stated that there is also a relationship with the production of this type of waste, since some of these countries are also the world's largest producers of castings and consequently of foundry waste, such as China, India, the USA, Brazil, and Russia. These five countries are responsible for about 42% of the existing publications, thus highlighting their prominent  
Figure 5: Trend of publications on foundry wastes over time (1986–2023). role in this field of study and indicating a correlation between waste production and research activity. Figure 7 presents the scientific areas that have developed the most scientific articles in this research domain. These five areas are responsible for about 72% of the publications. The contributions of the environmental sciences suggest a focus on environmental impact, and the significant number of publications in materials science and construction technology highlights the interdisciplinary nature of research on foundry waste, as these areas are important for the development of sustainable materials and construction practices. The relationship between this research domain and the Sustainable Development Goals (SDGs) defined by the United Nations is closely linked to the studies developed in \"foundry waste\" (Figure 8). The correlation between studies on foundry waste and the SDGs demonstrates an alignment that will allow addressing the main global sustainability challenges, acting on various objectives and targets of the 2030 Agenda. About 60% of the published articles are related to Goal 12: Responsible Consumption and Production, making it the most relevant, as it is related to waste management, including the reduction, reuse, and recycling of materials, highlighting the importance of foundry waste management. Figure 6: Top 10 countries by number of publications on foundry waste. Figure 7: Research areas with the most publications on foundry waste. The last analysis was created using VOSviewer (Version 1.6.20), with the same database. This analysis generated an image that shows the most relevant keywords in this investigation, using the topic \"foundry waste\" (Figure 9). Keywords are visualized based on their frequency and co-occurrence, with size and connections indicating their importance and relationships. The color gradient represents the average year of publication, highlighting both past and current trends in foundry waste research. The most common keywords are \"waste foundry sand\" and \"concrete\", which demonstrates that they are important topics in the research literature. \"Recycling\", \"mechanical properties\", \"durability\", and \"compressive strength\" are other relevant terms.