Experimental Investigation of Thermally Induced Interacting Cracks in Brittle Solids

AbstracbThe results of an experimental investigation of thermally induced parallel edge cracks in a half-plane consisting of brittle material are reported. A free edge of a glass plate heated to a uniform temperature, was brought in contact with a liquid bath cooled by dry ice. The thermal contraction of the boundary layer produced interacting tension cracks. When no initial cracks existed, a large amount of potential energy was released in the formation of a few cracks which extended in a dynamic manner beyond the thermal layer. To prevent this type of cracking, initial cracks were formed before thermally inducing crack growth. This resulted in stable crack growth which qualitatively agreed well with the previously developed theory. The quantitative comparison was also reasonably good.