Discovering the technology evolution pathways for 3D printing (3DP) using bibliometric investigation and emerging applications of 3DP during COVID-19

Additive manufacturing (AM) is advantageous in terms of lower carbon emissions, less material-wastage, mobility of digital design, product customization and simpler supply chain management. Moreover, during the global COVID-19 crisis, a robust and IT-driven manufacturing technology was highly required to cope with the peak demands of medical and basic emergency supplies. 3D printing (3DP) enabled the manufacturers to fulfill the deficiencies of healthcare equipment for medical professionals and patients throughout the world. In this paper, some emerging applications and challenges incurred by 3D printing during COVID-19 were briefly summarized. 3D printed PLA-based biodegradable mask filters, medical face shields, respiratory protective equipment and 3D bioprinted tissue models for COVID research are some significant contributions of AM. In this paper, a CiteSpace based bibliometric investigation of 3DP-related literature was conducted, to identify the technology evolution pathways for 3D printing, using the data retrieved from Web of Science and published between 1986 and 2021. The main contributing forces including countries, journals, institutions and subject areas were determined. Knowledge clusters were established to identify networks of the most prolific keywords and documents. In addition, a hierarchical knowledge foundation and hotspots of 3DP were recommended for future research. It was revealed that the policy support of the USA, China, England and Germany was significantly favorable for the development of 3DP research. This article provides insights into the COVID-based applications of 3DP and the research dynamics of this field, which can help in the decision-making process to incorporate innovative and emerging technologies in the AM industry.