IRON NICKEL ALLOY SUPER-INVAR 32-5 ; (Composition (Nominal): 0.02 C, 0.40 Mn, 0.25 Si, 32 Ni, 5.5 Co, Bal. Fe ; : (Super Invar 32-5 is A low expansion alloy consisting of 32% Nickel, 4% Cobalt, and balance Iron. Super Invar 32-5 Alloy exhibits minimum thermal expansion at room temperatures (one half of Invar 36), as well as thermal expansion properties less than that of Invar Alloy in the 67/203°F (-55/95°C) temperature range. ; (Specifications: ASTM F1684 ;: (Product availability and request a QUOTE!