High-throughput printing of functionally gradient material from self-propagation

The development of new materials is of great significance for scientific and technological innovation and is essential in addressing significant societal challenges (1). Combinatorial material deposition techniques facilitate the understanding of composition-structure-property relationships and permit the rapid screening of materials across diverse compositional ranges (2). However, there are considerable challenges associated with the universal integration of multiple materials and the creation of gradient material libraries due to the lack of efficient mixing mechanisms and the difficulty in achieving precise and rapid dispensing (3-5). In this study, we introduce a novel printing approach for multicomponent gradient materials, which amalgamates various constituent materials for the three-dimensional printing of multiscale and high-throughput multigradient materials. This innovation overcomes the limitations of prolonged cycle times, high experimental costs, and low efficiency inherent in traditional manufacturing methods. First, we developed 3D-printed precursor materials that can be shaped arbitrarily. By meticulously proportioning the components of these precursor materials through high-throughput techniques and material libraries, we enable multi-degree-of-freedom adjustments in ratios and on-demand combinations, resulting in the fabrication of complex materials not achievable through conventional manufacturing processes. Subsequently, we established a highly adaptable self-propagating energy deposition technology based on the precursor materials, which reduces the conventional reliance on specific equipment and processes. Finally, we demonstrated the application of this technology through a printing strategy for various copper-based composites and multicomponent gradient materials, which allows for the simultaneous incorporation of an array of metallic and non-metallic compounds with graded properties across multiple compositions and structures. This advancement significantly enhances the scope of additive manufacturing applications in composition optimization, functional grading, and structural tuning, surpassing the capabilities of traditional printing methods. Our ability to synchronize the printing of multilayer gradient materials during the process, while mitigating thermal accumulation and structural defects such as cracks through thermal stacking between gradients, represents a marked improvement over traditional hot-cold stacking methods. Furthermore, we transitioned from the conventional outside-in model of additive manufacturing—where methods and equipment dictate the consumables—to a novel inside-out model, whereby consumables inform the methodology and equipment. Such a paradigm shift will facilitate the development of new functionally graded materials with unique compositions and structural arrangements unattainable through established manufacturing techniques.