In this study, bulk net-shape pure magnesium was fabricated by selective laser melting (SLM). Effects of Mg particle size and processing parameters on the properties of SLM specimens were investigated. The scan speed and laser power were optimized based on macro-observation of the forming process and resulted specimens. Through the comparison analysis of topology, density, and micro-hardness, it was found that the bulk magnesium specimen made of −250 mesh powder showed better results than that made of −400 mesh powder. The relative densities of both SLM specimens were over 95%, and their micro-hardness values were higher than that of as-cast magnesium. It was also revealed that the scanning time interval (STI), as a relatively new processing parameter, had an obvious effect on the properties of SLM bulk magnesium in terms of surface morphology, roughness, and micro-hardness.

Magnesium (Mg) and its alloys are receiving increasing attention in peripheral nerve regeneration, but they were limited due to the low corrosion resistance and rapid degradation. In this study, GDNF-Gel/HA-Mg was prepared and its value in peripheral nerve defects repairment was explored both in vitro and in vivo. A hydroxyapatite (HA) coating was first applied to the pure Mg surface, followed by the formation of gelatin methacrylate (GelMA) loaded with glial cell-derived neurotrophic factor (GDNF) on the HA-coated Mg surface. GDNF-Gel/HA-Mg corrosion resistance was explored. The effect of GDNF-Gel/HA-Mg conduit on Schwann cell proliferation and migration abilities were investigated. And sciatic nerve defects models were established to explored the role of GDNF-Gel/HA-Mg conduit in peripheral nerve defects repairment. The electrochemical, immersion, and hydrogen evolution experiments indicated that the corrosion resistance in phosphate buffer saline (PBS) of pure Mg was significantly improved by the GDNF-Gel/HA coating. Cell cycle, Cell Count Kit-8 (CCK-8), and clone formation assays indicated that GDNF-Gel/HA-Mg promoted the proliferation of Schwann cells. Scratch and Transwell assay results demonstrated that GDNF-Gel/HA-Mg promoted Schwann cell migration ability dose-dependently. GDNF-Gel/HA-Mg was found to enhance the secretion of nerve growth factor (NGF) and the expression of p75^NTR. Flow cytometry results showed that GDNF-Gel/HA-Mg could reduce H₂O₂-induced oxidative stress and Schwann cell apoptosis. GDNF-Gel/HA-Mg inhibited M1 macrophage polarization while facilitated M2 macrophage polarization in a concentration-dependent manner. The in vivo studies demonstrated that GDNF-Gel/HA-Mg conduit could significantly promote the regeneration and myelination of sciatic nerve, as well as the recovery of denervated gastrocnemius atrophy. The GDNF-Gel/HA-Mg conduit prepared in this study exhibited good hydrophilicity and corrosion resistance and greatly enhanced the proliferation, migration, and invasion abilities of Schwann cells, as well as peripheral nerve regeneration.

An AgPd30/CuNi18Zn26 bilayer laminated composite (BLC) was manufactured by hot-roll bonding followed by two passes of cold-rolling and three passes of annealing. The evolution of the interface microstructure during the manufacturing process was investigated using a scanning electron microscope, an electron probe microanalyzer, an X-ray diffractometer and a transmission electron microscope. It was found that a net atomic flow of Zn and Cu immigrated from the CuNi18Zn26 layer into the AgPd30 layer, leading to the formation of a Cu₃Au-type superstructure of Cu₂NiZn in the former and a diffusion layer in the later. The clusters enriched in Zn and Pd were formed in the diffusion layer and their number varied during the rolling and annealing process. The thickness of the diffusion layer was increased by annealing and decreased by cold rolling. Several intermetallic compounds were identified, which are Pd₂Zn, PdZn, Pd₂Zn₃, PdZn₂, Pd₃Zn₁₀ and Cu₃Pd. Some orientation relationships between the compounds and the AgPd30 alloy were determined to be (310)_PdZn2//(111)_AgPd and (114)_Cu3Pd//(311)_PdZn2//(321)_Pd3Zn10. Delamination occurred in all 6 samples during tensile testing, including an as-bonded one, two as-rolled ones and three as-annealed ones, but its degree decreased successively with the progress of rolling and annealing. Two turning points appear on the tensile curves of as-annealed samples, which are ascribed to the initiation of delamination and the yield of the metal matrix. However, the tensile curves of the as-bonded and as-rolled samples are smooth.

A novel dual-face hot-roll inlaying technique was developed to fabricate a Ag/Cu through-layered composite for use in melt elements for fuse production, including two stages of grooving in a Cu strip followed by separate inlaying of Ag strips at the same positions on the opposite surfaces. The microstructure was characterized using field emission scanning electron microscopy (FE-SEM), electron probe microanalysis (EPMA), X-ray diffraction (XRD), and selective area electron diffraction (SAED). The Ag/Cu interfaces are flat and well bonded, with an elemental interdiffusion layer of less than 2 μm. The same textural components—copper, brass, and S-type components—were identified in both the Ag and Cu layers. However, no well-matched crystal orientation relationship between Ag and Cu was detected at the interface. Moreover, tensile properties and electrical resistance were measured to evaluate the bonding strength and conductivity of the interface. It was found that Ag/Cu bonding strength surpassed the tensile strength of Ag, i.e., 260 MPa. While the total elongation is less than 1%, the Ag layer exhibits excellent plasticity, with a section shrinkage over 90%. Compared with the calculated resistivity with a series circuit model, the tested value of the composite sample, including six Ag/Cu interfaces, increased by only 6.6%, indicating good conductivity of the Ag/Cu interface. Therefore, the obtained composite is a promising candidate for the fabrication of melt elements.