In this work, high‐density lithium disilicate (LS2) vitreous systems were produced by melting and quenching under high pressure (7.7 GPa) following two distinct experimental routes. In the first case, LS2 glass was remelted at 7.7 GPa and 1600°C and, then, quenched. In the second case, a stoichiometric mixture of precursor oxides (Li2O and SiO2) was melted at 1600°C and 7.7 GPa before quenching. A reference LS2 glass sample was produced at atmospheric pressure using conventional melting and quenching procedure. The samples were characterized by X‐ray diffraction, differential thermal analysis, and instrumented ultramicro hardness measurements. X‐ray diffraction confirmed that all samples were amorphous and thermal analysis suggests that different glassy structures were produced depending on the route of synthesis. Hardness and elastic modulus of the glasses produced under high pressure were higher than those of the reference glass, reflecting the irreversible densification effect induced by the high‐pressure processing.

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The mechanical alloying of Mo-Cu powders allows the production of highly homogeneous sintered pieces, with very thin Mo particles and good dispersion of Mo particles in the ductile Cu phase, allowing the development of a route for the preparation of Mo-Cu simple composite powders, environmentally sustainable and able to increase the sinterability of the material without causing damage to their properties of thermal conductivity and electrical. Was used the precursor powders of molybdenum (Ammonium heptamolybdate) plus Cu, where two samples were prepared by mixing processes. For mechanical alloying, and by mixing manually, and both reduced and sintered in a resistive furnace with hydrogen gas. The materials were analyzed by optical microscopy, XRD and density measurements. The results confirm the effect of mechanical alloying on the increasing in high density of the sintered samples and thereby producing superior properties to those shown by the mixing manually sample.

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