4330 MOD Vac Melt N&T (Normalized & Tempered) is aircraft-quality, low-alloy steel that is multiple melted using the vacuum arc remelting (VAR) practice as the final melting process. Vanadium is added to improve impact strength and hardenability. The lower carbon content makes this material useful in products that require stress concentration or shock loading. This alloy is used to produce parts requiring high tensile strength and good ductility and when heat treated provides high impact strength, superior transverse properties, and hardness. Certain design and processing procedures may cause these products to become susceptible to stress-corrosion cracking after heat treatment. ARP1110 recommends practices to minimize such conditions. This material is often used in the aerospace industry for structural components, shafts, springs, axle components, tie rods, pinions, and castings. (UNSK23080)
