ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Influence of recycled PV glass content and holding time on the sintering behavior, microstructure, and functional properties of high-alumina ceramics

Truong Bach Chien and Nguyen Hoc Thang

Faculty of Chemical Engineering, Ho Chi Minh City University of Industry and Trade, Ho Chi Minh City, Vietnam

E-mail: thangnh@huit.edu.vn

Received: 16 November 2025  Accepted: 5 May 2026

Abstract:

A sustainable way to lower the high energy consumption associated with the conventional alumina-based ceramic production process is to use recycled photovoltaic (PV) glass as a sintering aid. In order to assess the densification behavior, microstructural alterations, and functional characteristics of high-alumina ceramics containing 5–20 wt% PV glass, the ceramics were heated to 1600 °C for two to six hours. The findings show that PV glass functions as a dual-purpose additive, influencing grain boundary properties as a microstructural modifier and acting as a fluxing phase to facilitate liquid-phase sintering. Densification was greatly improved by increasing the PV glass up to 15 weight percent, as shown by decreased apparent porosity and increased bulk density and shrinkage. In optimal conditions (15 wt% PV glass, 4 h sintering holding time), the high alumina ceramics achieved a bulk density of 3.79 g/cm³ and a low porosity of 4.85%. With a maximum flexural strength of 385 MPa, fracture toughness (Kᵢc) of 4.7 MPa·m^1/2, and Vickers hardness of 1380 HV1, mechanical properties were also enhanced. Additionally, the dielectric characteristics were improved, showing good electrical insulation behavior with a breakdown strength of up to 27.5 kV/mm and a low dielectric loss. However, due to glass phase segregation and potential over-sintering effects, high glass content (> 15 wt%) or long sintering holding time (≥ 6 h) resulted in minor property degradation. These findings imply that, when properly optimized, recycled PV glass can effectively encourage densification and improve the mechanical and dielectric performance of high-alumina ceramics. However, to prevent negative consequences linked to excessive liquid-phase formation, careful control over glass content and sintering conditions is necessary.

Keywords: Recycled photovoltaic (PV) glass; High-alumina ceramics; Sintering behavior; Mechanical and dielectric properties; Sustainable ceramic processing

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-05020-z

Chemical Papers 80 (9) 10471–10489 (2026)