Form This specification covers an aircraft-quality@ low-alloy steel in the form of sheet@ strip@ and plate. Application These products have been used typically for use where welding and moderate tensile properties are required@ but usage is not limited to such applications. Sheet and strip are extensively used where minimum tensile strength of 180 ksi (1241 MPa) is required in sections up to 0.125 inch (3.18 mm) in nominal thickness and proportionately lower strength is required in heavier thicknesses.