Orthotropic material

A material whose properties vary along three perpendicular directions, usually associated with the material's grain direction. Nine elastic constants (three moduli of elasticity, three shear moduli, and three Poisson's ratios) are required to fully characterize an orthotropic material. The practical consequence is that, for an orthotropic material, the wave speed is not the same in every direction. Thus, for a given horn design and specified frequency, the horn's tuned length will depend on which direction that the horn was machined from the original material.

Titanium bar is somewhat orthotropic. Titanium plate, if properly rolled, is less orthotropic than titanium bar. See titanium.

Also see —
Anisotropic
Homogeneous
Isotropic