Effect of Crack Pattern on the Residual Strength of Ceramics After Quenching

Abstract

The physical mechanisms between residual strength and crack characteristic of ceramics after water-quenching are studied by statistically measuring the cracks in ceramic sheet. The result herein reveals that in the joint action of long crack length and density, the residual strength is maintained at the same level within a temperature range above the critical thermal shock temperature difference (ΔT C ). The result presented herein forms a further comprehension to the ceramics behaviors of and the theoretical approaches to thermal shock.

Initiation of a periodic array of cracks in the thermal shock problem: A gradient damage modeling

“…In the present paper we made explicit reference to the geometry and loading of the experimental setups for thermal shock on glass or ceramics of Shao et al (2010Shao et al ( , 2011Bahr et al (2010);Jiang et al (2012), where thin specimens of the typical size 50×10×1 mm are heated (300…”

“…Examples of such a situation come from various fields: civil engineering with the drying of concrete (Bisschop and Wittel, 2011), mechanical engineering with the exposure of glass (Geyer and S.Nemat-Nasser, 1982) or ceramics to a thermal shock (Bahr et al, 2010;Shao et al, 2010), geomaterials with the drying of soils (Morris et al, 1992;Chertkov, 2002;Goehring et al, 2009) or colloidal suspensions (Gauthier et al, 2010), and the thermal shocks in overexploited gas storage caverns (Berest et al, 2012). These cracks are of importance as they can weaken the body or govern future diffusion process, modify the strength of the material (Shao et al, 2011) or compromise the safety of the structure.…”

Characterization of thermal-shock cracks in ceramic bars

“…The characteristics of cracks generated by the changes of quench temperature are vital for understanding underlying mechanisms related to the thermal-shock. It is widely accepted that neither cracking nor residual strength undergo change at temperatures below the critical temperature, T c , however, the strength is significantly decreased at T c due to the cracks [3][4][5][6][7][8][9].…”

Effect of porosity on the crack pattern and residual strength of ceramics after quenching

“…Note that since the length of the long crack decreases slightly with increasing porosity as shown in Fig. 5, it plays a minor role in enhancing the proportion of residual strength [18,25]. However, despite the fact that proportion of the residual strength is significantly increased with porosity, the strength of porous ceramic, either before or after thermal shock, is less than the dense one.…”

“…Based on statistical data, we defined the crack [75 % of the longest crack length as the long crack [18]. The variations in length and density of the long crack in porous ceramics with different DT are shown in Fig.…”