Typical yield and ultimate strengths for armour material. Many of the values depend on manufacturing process and purity/composition. The sources include: wikipedia.com and alubra.com

Symbol
$\sigma_{\mathrm{y}}$
Unit
MPa
Related
$a_{\mathrm{constr}}$
Choices
MaterialYield strengthUltimate strength
ASTM steel250400
Stainless steel520860
Copper70220
Brass (CuZn)200550
Bronze (CuSn)120240
Aluminium alloy400455