“…All these options are typical for brittle fractures that most likely start at the stage of cooling down to T <TG. The problem of the formation, growth and destruction of MS with viscoplastic or viscoelastic shells is considered, for example, by Sheng and Azevedo 21) and Dacombe et al 64) , who studied the formation of fly FA and MS, Yao et al 114) and Ribe 135) , who attempted to develop a general theory of the dynamics of thin viscous films, Mungall et al 120,121) , who studied the cooling of volcanic lava or by van der Schaaf and Beerkens 136) who examined the behavior of glass spheres in the molten metal. The simplest scenario of the MS destruction at this stage involves breakthrough in the shell at t/D0 < (t/D0)cr accompanied by gas emission, possible loss of part of the shell, the subsequent collapse and reformation of an intact shell over a preserved core.…”