2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/16788The remarkable finding of this work is the linear correlation between the critical temperature of superconducting (SC) transition, Tc, and the room-temperature half-width of angular correlation of positron annihila- tion phonons (ACPAP), Go/2, in the series of powder samples of high-Tc YBCO(123) ceramic superconductors (SCs) with various deficiency of oxygen content. This correlation points to the existence of fundamental physical parameter of materials in all-temperature range,which is the crucial one for their insulator-metal-superconductor (IMSC) transition. We attribute this key-parameter to the rapid increase and then the steady (due to the minimal mechanical relaxation rate) lattice compressive deformation - the sudden and stable jump in work-hardening of crystals). The traces of this compression may be observed by different methods over a wide range of te- mperatures and used for the forecast of the parameters of technological interest for the new SCs.12 pagesSuperconductivitytext