CXII. On the theory of strength of quasi-isolropic solids

Abstract

It is shown that Sir Lawrence Bragg's theory of the strength of metals, which is based on the assumption of a block structure of the crystallites, and the author's thermodynamic theory of strength, which is based on the idea of a connection between breaking and melting, can be related to each other if it is assumed that the block structure is an intrinsic feature of the crystal lattice. This can further be linked up with some recent theoretical ideas of M. Born on the one hand, and on the other hand with new experimental observations on the broadening of X-ray lines of metals by W. A. Wood and his school. It appears that the size of the blocks, as determined from these experiments, has the same order of magnitude as the critical block size calculated from Born's theory. Some implications of the concept of an “intrinsic block structure” of crystal lattices are discussed.