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This study investigates H13 tool steel's microstructure and mechanical properties using selective laser melting (SLM) and electron beam melting (EBM). SLMed‐H13 steel has fine martensite, residual austenite, dense low‐angle grain boundaries (LAGBs), and nanoscale carbides, whereas EBMed‐H13 predominantly shows lamellar ferrite–bainite, needle‐like lower bainite (Blower), and spongy upper bainite (Bupper), with fewer LAGBs and larger carbides. SLMed‐H13 exhibits higher hardness (617.4 HV0.5) than EBM (532.17 HV0.5), with a yield strength (YS) of 1241.1 MPa, ultimate tensile strength (UTS) of 1412.2 MPa, and elongation (El) of 5.36%, versus EBM's 765.8 MPa YS, 1252.7 MPa UTS, and 6.89% El. SLM shows superior mechanical performance and wear resistance, with a coefficient of friction (COF) of 0.81, wear depth of 0.86 μm, wear track of 448.4 μm, and wear rate of 5.5 × 10−6 mm3 N−1 m−1, compared to EBM's 0.68 COF, 2.2 μm wear depth, 508 μm wear track, and wear rate of 6.5 × 10−6 mm3 N−1 m−1. Confocal microscopy highlights SLM's uniform wear tracks versus EBM's distinct microcutting, illustrating the impact of manufacturing techniques on material properties and wear performance. [ABSTRACT FROM AUTHOR]

In this work, CaO-MgO-Al2O3-SiO2 (CMAS) system alkali-free aluminosilicate glass was selected as the research object. Eight groups of Fe2O3 component variables were designed, and the experimental samples were prepared by high temperature melting method. XRD, SEM, TG-DSC and other test methods were used to tested and analyzed the phase, crystallization kinetics, crystallization behavior and elastic modulus of alkali-free glass samples, and then the effects of Fe2O3 content and crystallization treatment on the elastic modulus of alkali-free glass were discussed. The results show that the appropriate addition of Fe2O3 improves the elastic modulus of CMAS system alkali-free glass. When the mass fraction of Fe2O3 is 1.50% (F-6 #), the maximum elastic modulus of F-6 # alkali-free glass is 97.87 GPa, the crystallization activation energy is 347.1 kJ/ mol, and the crystallization index n is 1.383 4, which is surface crystallization. After crystallization treatment by bulk crystallization method, the main crystalline phase precipitated from F-6# glass-ceramics is anorthite phase (CaAl2Si2O8), and the crystal size is 200 ~400 nm. After crystallization treatment by sintering method, the main crystalline phase precipitated from F-6# glass-ceramics is anorthite phase (CaAl2Si2O8), and the crystal size is 300 ~ 500 nm. With the increase of heat treatment temperature, the number and size of the precipitated main crystal phase increase, but the type of the main crystalline phase keeps unchanged. However, because the elastic modulus of anorthite is smaller than that of the base glass, the elastic modulus of the glass-ceramics obtained after crystallization of F-6# alkali-free glass decreases. [ABSTRACT FROM AUTHOR]