Grayscale digital light processing 3D printing for highly functionally graded materials

Abstract

Three-dimensional (3D) printing or additive manufacturing, as a revolutionary technology for future advanced manufacturing, usually prints parts with poor control of complex gradients for functional applications. We present a single-vat grayscale digital light processing (g-DLP) 3D printing method using grayscale light patterns and a two-stage curing ink to obtain functionally graded materials with the mechanical gradient up to three orders of magnitude and high resolution. To demonstrate the g-DLP, we show the direct fabrication of complex 2D/3D lattices with controlled buckling and deformation sequence, negative Poisson’s ratio metamaterial, presurgical models with stiffness variations, composites for 4D printing, and anti-counterfeiting 3D printing.

Understanding the multiscale self-assembly of metal–organic polyhedra towards functionally graded porous gels

“…4 Inspired by biological systems, synthetic materials with such gradients have been designated as functionally graded materials (FGM), 5 and porous materials containing gradients can give unique mechanical properties and permeability, with applications in various elds from tissue engineering 6 to the aerospace industry. 7 In most cases, the fabrication procedures to engineer porosity have been limited to top-down approaches including microuidics 8 or 3D printing technologies; 9 indeed, inducing gradients of porosity over the mesoporous and microporous regimes remains a challenge.…”

Advanced Bottom‐Up Engineering of Living Architectures

“…On the same context these approaches can be further improved since, stereolithography‐based grayscale digital light processing is now emerging as an enabling tool for manufacturing functionally graded materials with location‐specific properties. This could allow 4D bioprinting of constructs with programmable buckling/deformation sequences . Multiphoton technology is also capable of eliciting topographical changes in protein‐based hydrogels via inner contraction of the structural network, thus allowing manipulation of cell microenvironment in 4D, but is still constrained by complex operation conditions and slow patterning rate .…”

Detailed Solution of a System of Singular Integral Equations for Mixed Mode Fracture in Functionally Graded Materials

“…appear to be at the material interface due to the sudden change of material composition. To cope with these failure issues, functionally graded materials (FGMs) are developed (Hirai, 1996;Kawasaki & Watanabe, 1990;Kaysser, 1998;Koizumi, 1993;Bhavar, 2017;Heer & Bandyopadhyay, 2018;Kuang et al, 2019). In FGMs, material compositions are engineered by controlling the material properties near and at the interface of the materials, so that material failures can be minimized.…”