Enhancing borosilicate glass vials through chemical strengthening

This study compares the mechanical properties of chemically strengthened borosilicate glass vials (BSGV) and Corning's aluminosilicate glass vials (Valor®). A trade-off exists in BSGV between surface compressive stress (CS) and depth of layer (DOL), varying with temperature and strengthening duration. Compared with Corning's Valor®, ion-exchanged BSGV exhibited up to 55 % lower CS (at 500 °C for 4 h) and 89 % lower DOL (at 400 °C for 1 h). These variations derive from sodium content differences and the glass structural network; however, both ion-exchanged BSGV and Valor® demonstrated internal pressure (IP) strengths surpassing the 60 bar limit of our testing equipment at 450 and 500 °C. BSGV undergoes strengthening at 400 and 450 °C for extended durations, gradually enhancing hardness (Hv) and elastic modulus (E). BSGV strengthened for 4 h at 450 °C showed mechanical properties approaching those of Valor®. Conversely, at 500 °C, prolonged strengthening times caused reductions in Hv and E owing to the rearrangement of the network structure and stress relaxation.