Materials Today Communications 39 (2024) 109247 Available online 16 May 2024 2352-4928/© 2024 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies. Contents lists available at ScienceDirect Materials Today Communications journal homepage: www.elsevier.com/locate/mtcomm B 2 O 3 anomaly effect on crystallization and mechanical properties of soda-lime silicate glasses Santosh Kumar a , K. Singh a, , Devender Kumar b a School of Physics and Materials Science, Thapar Institute of Engineering and Technology, Patiala 147004, Punjab, India b Department of Mechanical Engineering, Thapar Institute of Engineering and Technology, Patiala 147004, Punjab, India ARTICLE INFO Keywords: Makishima–Mackenzie model Rocherulle model Activation energy Bulk crystallization ABSTRACT In the present investigation, the effect of B 2 O 3 is investigated on the theoretical mechanical properties and crystallization kinetics of (64-x)SiO 2 -xB 2 O 3 - 16Na 2 O - 12CaO -2Al 2 O 3 -6MgO (x = 2, 4, and 6 mol%) glasses. To understand the mechanical properties elastic moduli are calculated using two theoretical models i.e., Makishima–Mackenzie and Rocherulle. Whereas, in crystallization kinetics, activation energies ( , , and ) are computed using two distinct methods, i.e., the Kissinger model and the Augis and Bennett model. The replacement of SiO 2 by B 2 O 3 enhances the strengthening of the glass network which makes the B6-S58 glass network more rigid. The B6-S58 and B2-S62 glasses have the highest and lowest activation energy ( ) for crystallization, respectively. B4-S60 glass shows non-linear behavior in characteristics temperature as well as in activation energy due to boron anomaly. The present finding could be helpful in designing windshield automobile glasses. 1. Introduction Oxide glasses are extremely valuable and reliable materials used in energy conversion, optoelectronics, pharmaceuticals, and storage systems, among other fields in modern life [1,2]. The properties of glass can be tuned easily by changing its composition and constitution [3 5]. Further glasses can be transformed into glass ceramics with superior mechanical properties as compared to glasses. Mixed alkali and alka- line earth metal oxides incorporating borosilicate glasses have been thoroughly explored for a range of functional and health benefits [3]. Alkali and alkaline earth metal oxides alter the physical, optical, chemical, and thermal properties of glasses by decreasing the number of bridging oxygens (BOs) per tetrahedron along with increasing the number of non-bridging oxygens (NBOs). Various types of silicate ( , where n is the number of BOs) and borate units (BO 4 , BO 3 ) play an important role in altering the properties of borosilicate glasses. The triangular units are forced into tetrahedral coordination (BO 4 ) transition without any formation of NBOs with the addition of alkali oxide [6]. As a result, the glass transition temperature ( ) increases with increasing glass network connectivity. Moreover, in borate glasses, falls with increasing alkali content which is associated with the ‘‘boron anomaly’’ [6,7]. Alkali oxide containing borosilicate glasses has a complex structure due to the formation of BO 4 units at the cost of BO 3 units. On the other hand, the silica network is not changed with containing zero NBOs. However, the properties of borosilicate glasses Corresponding author. E-mail address: kusingh@thapar.edu (K. Singh). are changed due to the formation of NBOs with the addition of higher content of alkali oxide [8]. Alkali metal oxides (Na 2 O) and alkaline earth metal oxides (MgO) usually act as the glass modifier in silicate glasses. However, MgO and Na 2 O also act as a glass former depending upon its concentration and glass composition [9]. From an application point of view, it is necessary to understand the mechanical properties of glasses with varying compositions with two different glass formers like SiO 2 and B 2 O 3 . The elastic modulus, silicon–oxygen bond density, and bond strength are likely related to the overall strength having multiple network modifiers and formers. According to Doremus’s theory, silicate glasses with modifiers exhibit less strength in comparison to crystalline SiO 2 [10]. Still, the difference in strength would be negligible at most a factor of two. The tensile strength, elastic modulus, and modulus of rupture (MOR) of a sodium silicate glass were examined by Gehlhoff and Thomas after they added various oxides in glass composition [11]. The replacement of SiO 2 with B 2 O 3 significantly enhanced the elastic modulus and strength of the glass compared to using similar substitutions of Al 2 O 3 . Furthermore, knowledge of the kinetics of crystallization is cru- cial to assess the thermal stability and glass transition behavior of the borosilicate glasses [12]. The characteristic temperatures that are important to study the structural changes with the composition of the glasses are obtained by differential scanning calorimetry (DSC) [13]. https://doi.org/10.1016/j.mtcomm.2024.109247 Received 25 March 2024; Received in revised form 5 May 2024; Accepted 13 May 2024