Aluminium Copper Stainless Steel A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Ultimate Tensile Strength, Tensile Strength The maximum load, in tension, that a material can withstand before breaking. It is calculated as a breaking load for a standard cross section area and measured in Newtons per square mm (Nmm-2) or Mega-Pascals (MPa).