Critical appraisal and systematic review of 3D & 4D printing in sustainable and environment-friendly smart manufacturing technologies

Over the last few decades, advances in three-dimensional (3D) and four-dimensional (4D) printing techniques have made at ease to fabricate accurate biological components and complicated 3D geometrics. 3D printing (3DP) and 4D printing (4DP) technologies are sustainable and environment friendly, and are currently in process of bringing industrial revolution in various sectors including pharmaceuticals, chemicals, medical, aviation, defense, automotive, space etc. In this review, we have systematically reviewed the advancements in 3D and 4D printing technologies in last ten years and argued, how these techniques have brought revolution and sustainability in industrial development compared to the traditional manufacturing technologies. The research articles selected for this study were searched over online web-databases viz Google Scholar, EMBASE, PubMed and Web of Science. The search keywords used were: ((“three-dimensional printing technique” OR “3D printing technique” OR “Four-dimensional printing technique” OR “4D printing technique”) AND (“Applications” OR “Uses” OR “Manufacturing” OR “Additive manufacturing” etc.)). Few more search keywords like sustainability, eco-friendly, smart materials, polymers, and industrial development were used in combination with 3DP and 4DP technologies. The search was limited for last ten years (2013−2022). The retrieved studies were checked for their relevancy and publication year. Literature search revealed that 3D and 4D printing have diverse applications across various manufacturing industries including potential use in medical and pharma-technology. For instance, 4D printed objects can change their shape by themselves over the influence of external stimuli, such as light, heat, electricity, magnetic field etc., that can play diverse role in medical technology for e.g., 4DP offers rapid development with its capability of customization of smart orthopedics implants, spinal deformities, fracture fixation, joint and knee replacement. The technique of additive manufacturing (AM) has been used to build a solid 3D parts straight from computer-aided design data, and has been increasingly popular in recent years across a variety of industries. AM allows for large adjustments in production costs, energy consumption as well as production lead times. Keeping the humongous potential of 3D & 4D printing in view, we can conclude that still 3DP/4DP pertinent research is in the nascent stage and future intensive research dealing with its deep amalgamation with artificial intelligence techniques is warranted.