Abstract: Specimens for evaluating corrosion protection of substrates due, at least in part, to coatings applied thereupon are described. A specimen (1) comprises: a first coating (10), comprising a first set of layers (11) including a first layer (11A), on a first substrate (12); and a first set of perforations (100), including a first perforation (100A) and a second perforation (100B), in the first coating (10), wherein the first perforation (100A) has a first depth D1 through the first coating (10) and a first dimension W1 transverse to the first depth, wherein the second perforation (100B) has a second depth D2 through the first coating (10) and a second dimension transverse to the second depth D2 and wherein the first dimension W1 and the second dimension W2 are different.

Abstract: EM field absorbing compositions, particularly lightweight magnetic and carbon loaded compositions. The composition finds particular use as a radar absorbing coating for structures. There are further provided coated surfaces comprising the composition, methods of absorbing EM radiation, and methods of use of such a composition, such that a surface coated in the composition is capable of absorbing EM radiation. An electromagnetic radiation absorbing composition comprising an admixture of carbon nanotubes present in the range of from 0.1 to 10 v/v % dried, magnetic particulates with an average longest dimension of at least 1 micron, present in the range of from 1 to 60% v/v dried, in a non-conductive binder; preferably the iron particulates are present in the range of from 15-30% v/v.