Before revision: Unit of toughness Tensile toughness (or , deformation energy, UT) is measured in units of joule per cubic metre (J·m−3) in the SI system and inch-pound-force per cubic inch (in·lbf·in−3) in US customary units .
After revision: Unit of toughness Tensile toughness (or deformation energy, UT) is measured in units of joule per cubic metre (J·m−3) in the SI system and inch-pound-force per cubic inch (in·lbf·in−3) in US customary units , or equivalently newton-metre per cubic metre (N·m·m−3),