In this study ceramic scaffolds of the bioresorbable and osteoconductive bioceramic β-tricalcium phosphate (β-TCP) were impregnated with the bioresorbable and ductile polymer poly(ε-caprolactone) (PCL) to investigate the influence of the impregnation on the mechanical properties of the porous composites. The initial β-TCP scaffolds were fabricated by the ice-templating method and exhibit the typical morphology of aligned, open, and lamellar pores. This pore morphology seems to be appropriate for applications as bone replacement material. The macroporosity of the scaffolds is mostly preserved during the solution-mediated PCL impregnation as the polymer was added only in small amounts so that only the micropores of β-TCP lamellae were infiltrated and the surface of the lamellae were coated with a thin film. Composite scaffolds show a failure behavior with brittle and plastic contributions, which increase their damage tolerance, in contrast to the absolutely brittle behavior of pure β-TCP scaffolds. The energy consumption during bending and compression load was increased in the impregnated scaffolds by (a) elastic and plastic deformation of the introduced polymer, (b) drawing and formation of PCL fibrils which bridge micro- and macrocracks, and (c) friction of ceramic debris still glued together by PCL. PCL addition also increased the compressive and flexural strength of the scaffolds. An explanatory model for this strength enhancement was proposed that implicates the stiffening of cold-drawn PCL present in surface flaws and micropores.

in terms of deciphering structure-property relationships and the nonaffine nature of glass mechanical behavior, of computational and computer-assisted methods for accelerated materials discovery, and of physicochemical insight at glass formation and synthesis in unconventional types of materials. Despite this progress, significant questions remain as to the fundamental role of structural heterogeneity and its consequences for the predictability of mechanical properties underlying the many applications of glass. Today's challenge is to translate new understanding of the physics of disorder, glass chemistry, and surface mechanics into tools that enable future glass products with adapted elasticity, strength, and toughness. We will therefore consider fundamental advances in relation to emerging glass applications. While the aforementioned physical insights have mostly been obtained by computational simulation of model systems, and often through the examination of metallic glasses, we will here focus on glasses suitable for visible transparency, in particular silicate glasses, such as a representative of today's most prolific glass devices, ranging from ultrathin substrates to strong and visually transparent cover materials. We will further consider hybrid glasses and glass-like composite materials as emerging alternatives that may overcome the ubiquitous conflict between strength and toughness. [1] Glasses are materials that lack a crystalline microstructure and long-range atomic order. Instead, they feature heterogeneity and disorder on superstructural scales, which have profound consequences for their elastic response, material strength, fracture toughness, and the characteristics of dynamic fracture. These structure-property relations present a rich field of study in fundamental glass physics and are also becoming increasingly important in the design of modern materials with improved mechanical performance. A first step in this direction involves glass-like materials that retain optical transparency and the haptics of classical glass products, while overcoming the limitations of brittleness. Among these, novel types of oxide glasses, hybrid glasses, phase-separated glasses, and bioinspired glass-polymer composites hold significant promise. Such materials are designed from the bottom-up, building on structure-property relations, modeling of stresses and strains at relevant length scales, and machine learning predictions. Their fabrication requires a more scientifically driven approach to materials design and processing, building on the physics of structural disorder and its consequences for structural rearrangements, defect initiation, and dynamic fracture in response to mechanical load. In this article, a perspective is provided on this highly interdisciplinary field of research in terms of its most recent challenges and opportunities.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202109029.

Porous materials, such as metal-organic frameworks emerge to solve important quests of our modern society, such as CO2 sequestration. Zeolitic Imidazolate Frameworks (ZIFs) can undergo a glass transition to form ZIF-glasses; they combine the liquid handling of classical glasses with tremendous potential for gas separations. Using millimeter-sized ZIF-62 single crystals and centimeter-sized ZIF-62-glass we demonstrate scalability and processability. Further, following the evolution of gas penetration into ZIF-crystals and ZIF-glasses by IR microimaging techniques enables to determine diffusion constants and changes to the pore architecture on the Angstrom-scale. The evolution of ZIF-glasses is observed in situ using a microscope heating stage. The pore-collapse during glass-processing is tracked by changes to density and volume of the glasses. Mass spectrometry investigates the crystal-to-glass transition and thermal processing ability.

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The influence of different polarization states during the generation of periodic nanostructures on the surface of carbon fibers was investigated using a femtosecond laser with a pulse duration τ=300  fs, a wavelength λ=1025  nm, and a peak fluence F=4  J/cm². It was shown that linear polarization results in a well-aligned periodic pattern with different orders of magnitude concerning their period and an alignment parallel and perpendicular to fiber direction, respectively. For circular polarization, both types of uniform laser-induced periodic surface structures (LIPSS) patterns appear simultaneously with different dominance in dependence on the position at the fiber surface. Their orientation was explained by the polarization-dependent absorptivity and the geometrical anisotropy of the carbon fibers.

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Light emission in response to mechanical stimulation-termed mechanoluminescence (ML)-enables the optical detection and visualization of mechanical strain. In particular, materials with ML response in the transmission window of aqueous media or biological tissue enable in situ stress level monitoring, biophysical imaging or mechanically induced light delivery. However, most of today’s ML materials are polycrystalline ceramics or ceramic particle composites, which puts constraints on their bulk processability, material homogeneity and optical transparency. Here, we demonstrate ML from highly transparent glass ceramics comprising of a high-volume fraction of extraordinarily small Cr3+-doped ZnGa2O4 (ZGO) crystals embedded in a binary potassium germanate glass matrix. The ZGO phase is precipitated directly from the precursor glass by homogeneous nucleation in a narrow temperature window; entropic phase separation and a self-limited crystal growth rate yield a crystal number density above 1023 m-3. The residual glass matrix encapsulates these crystals in a dense, highly homogeneous material, whereby the microstructural stability and the extended supercooling range of the glass enable glass-like processing, for example, in the shapes of fiber, beads or microspheres.

Mechanical performance and consumer product safety have been major drivers for glass research and innovation. Commodity glass materials are brittle and, thus, their mechanical performance is extremely sensitive to the presence of microscopic flaws and defects at their surface: the extent by which surface flaws reduce the practical strength of glass products exceeds the effect of any optimization in glass composition by several orders of magnitude. 1 Strength-reducing flaws are created already during glass manufacture 2,3 : the intrinsic strength levels which are expected from theoretical considerations can be approached experimentally only on carefully drawn glass fibers which are basically free of microscopic defects. 4,5 For other types of glass products, processes such as acid-or fire-polishing are often applied in order to create defect-free surfaces. Such post-processing does not only reduce the presence of surface defects or flaws on pristine glass articles, but may also lead to a more persistent enhancement of product durability by generating surface gradients in chemical composition, mass density and residual stress.The most prominent post-processing methodologies for enhancing the strength of glass products rely on diffusive