Effect of heat treatment on chemical durability and TL dosimetric properties of Na2O-SrO-B2O3 glass system

Abstract

Na 2 O-SrO-B 2 O 3 glass system prepared by the known melting-quenching method was applied to a progressive heat treatment (HT) at 600 °C for 4, 6, 8 and 10 h. Glass (G) and its corresponding heat treated (HT) samples were characterized by density, molar volume and XRD technique that revealed the complete amorphous structure of the glassy matrix and the coexistence of two crystalline phases in the corresponding glass ceramics ; monoclinic phase of NaSrBO 3 and the triclinic phase of sodium strontium pentaborate Na 3 SrB 5 O 10 . Testing chemical durability of G and HT samples at 95 °C for 24 h, revealed higher chemical stability in aqueous (H 2 O) and acidic (H 2 SO 4 ) solutions, while the highest leachability was detected in the alkaline medium (NaOH). pH of leaching solution was found to control the leaching process and displayed rising behavior with time of immersion. The progressive rising of leaching solution temperature; 25, 40, 60 and 95 °C, revealed a quiet leachable enhancement as well. SEM photographs represented rough and heterogeneous surface morphology with continual leaching and the formation of colloidal layers at the later stages of corrosion.The TL-dosimetric properties indicated extremely higher thermoluminescence properties of HT samples than the untreated glass. The analysis of the exhibited TL signals revealed the composition of the glow curves of the treated and untreated samples of eight TL components. The obtained results recommend the acceptable chemical durability of the heat treated samples especially in the neutral medium that displayed no more than 8.5% leachability rate yearly, besides their promising TL-dosimetric features, accordingly their possible application in the field of radiation dosimetry . • Progressive thermal treatment of Na 2 O-SrO-B 2 O 3 glass at 600 °C displays hopeful chemical and thermoluminescent features. • The highest chemical durability of the obtained glass ceramics was detected in the neutral medium at 95°C for 24 h. • Glass-ceramics displayed acceptable chemical durability in H 2 O solution does not exceed 8.5 weight loss% per year. • Effect of temperature, pH and SEM are with agreement with chemical durability results. • Heat treatment is favorable for giving glass the highest TLD properties and promising radiation dosimetric properties.