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The 316L stainless steel powder injection molding feedstock was prepared by melt mixing with polyethylene glycol/epoxy resin (PEG-EP) as the powder surface modifier and polyformaldehyde resin (POM) as the binder system. The sintered 316L samples were obtained by nitric acid catalytic degreasing and sintering. The encapsulation effect of PEG-EP on 316L stainless steel powders and the influence of PEG-EP surface treatment on the properties of 316L stainless steel powder injection molding feedstock and the sintered specimens were studied by Fourier transform infrared spectroscope, scanning electron microscope, contact angle measuring instrument, rotary rheometer, universal material tester, metallographic microscope, carbon-sulfur analyzer, and microhardness meter. The results show that, PEG-EP are successfully coated on the surface of 316L steel powders, which improves the interface compatibility between 316L stainless steel powders and POM and enhances the feedstock fluidity, the mechanical properties of raw billets, and the mechanical properties and hardness of the sintered samples. When the PEG-EP mass fraction is 0.662% and the powder loading (volume fraction) is 63%, the tensile strength, fracture elongation, and bending strength of the 316L injection raw billets are 10.57 MPa, 8.38 %, and 21.24 N·(mm2)−1, respectively. The grain size, the maximum tensile strength, and the Vickers hardness of the sintered sample are 50.8 μm, 688 MPa, and 151 HV, respectively, leading to the best comprehensive performance.

Acquiring physical and mechanical strain information of the human body with wearable strain sensors can provide essential data from personal healthcare to human‐machine interfaces and others. Recent research reveals that CO2 laser scribing can convert polyimide films into porous graphene sponges under ambient atmospheres. However, the electrically conductive laser‐induced graphene (LIG) film mismatches with the tough and rigid plastic substrates when it is employed as stretchable strain sensors. In this work, by leveraging the advantageous properties of atoms‐level configured defects within crystalline LIG and heat transfer printing techniques, a flexible LIG‐SEBS (styrene‐ethylene‐butylene‐styrene) strain sensor is made. It is able to achieve exceptional electromechanical properties including a remarkable sensitivity in terms of gauge factor (413–3118), minimal hysteresis, and a broad strain range (>100% strain). Meanwhile, the SEBS‐LIG strain sensor has a stable and fast dynamic response and good repeatability. Additionally, the sensor can be integrated with a wireless communication module for remote monitoring of physiological signals in a real‐time manner with a smartphone App. [ABSTRACT FROM AUTHOR]

This study investigates the synergistic effect and mechanism of gelling materials with blast furnace slag (BFS), steel slag (SS) and desulphurization gypsum (DG) as the main components on the hardening of heavy metal ions by lead and zinc tailings. It is found that lead and zinc tailing (LZT) is mainly composed of dolomite and quartz and contain small amounts of calcium, aluminum, iron, magnesium and other elements as well as heavy metals such as lead and zinc. By the mechanical activation method, it is found that the lead and zinc tailings powder has the largest specific surface area and the highest activity index when the ball milling time is 2 h. At a hardening timepoint of 28 d, the calcite crystals in the samples are intertwined with the amorphous C-S-H gel (C-S-H gels are mainly composed of 3CaO∙SiO2 and 2CaO∙SiO2), which enhances the structural strength of the samples. The chemical reaction analysis confirmed that the formation of calcite is a major driver for the hydration reaction of the steel slag–desulphurization gypsum (SSSDG) system. Overall, the slag, steel slag and desulphurization gypsum solid waste-based gelling materials have synergistic effects in hardening heavy metals by limiting the leaching of metal ions, adsorbing metal ions and hardening heavy metals, and facilitating the hydration process through the formation of compound salt precipitates. [ABSTRACT FROM AUTHOR]