Physics of Desiccation Cracks

Speaker: Hisay Lama

Venue : HSB 209

Date : 21st December, 2018

Time : 5.30 p.m.

Abstract

Desiccation cracks forming on mud, old-paintings and particulate film, existing in various morphological form can be commonly observed in nature [1]. They are basically a mechanical defect that occurs as a result of mechanical instability generated during drying. Interestingly, very often they also exhibits self-similarity and were found to exist in plethora of morphological form. Though the origin of these drying driven cracks are known and is attributed to stress energy which is released during the process of drying [2]. But however, the origin of its existence in various morphological form is still a mystery. Researchers, have used colloid as a model system in order to understand desiccation cracks and has unveiled several mysteries. Several, analytical and computational models can also be found in literature explaining the origin of theses cracks and its propagation. In recent decade, study of desiccation cracks has also found lot of technological application especially for the fabrication of lithographic templates [3]. Various methodologies based on the principle of directed assembly are used to fabricate the periodic cracks. In this talk, I will focus on two aspects (i) concepts illustrating the desiccation cracks by performing model experiments and (ii) controlling the morphological form of cracks by invoking the principle of directed self-assembly [4].

Reference(s):

(1.) L. Gohering et al., “Desiccation cracks and their patterns: Formation and Modelling in Science and Nature”, John wiley and sons, 2015.

(2.) A. Gorissman and E. Kaplan, Euro Phys. Lett., 25, 415 (1994).

(3.) K. H. Nam et al. Nature (London), 485, 221 (2012).

(4.) Hisay Lama et al., Phys Rev Mater. 00, 005600, (2018).

About the speaker

Hisay Lama is a research scholar from Department of Physics at IIT Madras. He is working on drying induced mechanical instabilities in particulate film. He is working with Dr. Dillip Satapathy.