2006/12/31 by Andrew N. Norris · 1 citation
Engineering · Physics and Astronomy · #Composite Material Mechanics #Elasticity and Material Modeling #Elasticity and Wave Propagation #cond-mat.mtrl-sci
paper · pdf · doi:10.1093/qjmam/hbm007
published as Quart. J. Mech. Appl. Math. 60, 367-389, 2007. · 20 pages
arxiv created 2007/03/09 · openalex publication_date 2007/05/04 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A quadratic invariant is defined as a quadratic form in the elements of a tensor that remains invariant under a group of coordinate transformations. It is proved that there are seven quadratic invariants of the 21-element elastic modulus tensor under SO(3) and 35 under SO(2). This answers some open questions raised by Ting and Ahmad in this journal.