Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Auxetic behavior created by “rotating rigid equilateral triangles.” The stretching of these systems increases angle "a" that occurs between triangles, which produces an open structure, and hence, a negative Poisson's ratio. Note that after rotating triangles 60°, it is possible to double the longitudinal (Y) and transverse (X) dimensions.
