Auxetic structure with stress-relief features

A combustor liner comprising at least one wall that comprises a material exhibiting auxetic behavior and reduced stress, the material comprising:

• a pattern of non-intersecting void structures in the material, each void structure including a slot with two ends and a stress reducing portion at each of the two ends and each void structure being symmetrically arranged along an imaginary longitudinal or lateral line, so that the void structures of the pattern are arranged along a plurality of imaginary longitudinal and lateral lines that form a grid, wherein:
• the longitudinal lines are generally perpendicular to the lateral lines;
• an individual void structure arranged along an imaginary longitudinal line is flanked by multiple void structures arranged along lateral lines;
• an individual void structure arranged along an imaginary lateral line is flanked by multiple void structures arranged along longitudinal lines;
• and
• the stress reducing portions of the void structures are shaped to reduce stress concentrations at the ends of the slots and configured to deform under a load applied along the longitudinal lines or the lateral lines in a manner that results in the material exhibiting the auxetic behavior.