AL-6XN

The AL-6XN alloy is a superaustenitic stainless steel which was developed by Allegheny Ludlum Corporation. It exhibits far greater resistance to chloride pitting, crevice corrosion and stress corrosion cracking than exhibited by the standard 300 series stainless steels, and is less costly than the traditional nickel-base corrosion resistant alloys.^{[citation needed]}

The unified numbering system (UNS) designation of the AL-6XN alloy is N08367.

The high nickel (24%) and molybdenum (6.3%) contents of the AL-6XN alloy give it good resistance to chloride stress-corrosion cracking. The molybdenum confers resistance to chloride pitting. The nitrogen content of AL-6XN alloy serves to further increase pitting resistance and also gives it higher strength than typical 300 series austenitic stainless steels, and thereby often allows it to be used in thinner sections. The high levels of chromium, molybdenum and nitrogen in AL-6XN alloy all serve to produce exceptional corrosion resistance for this formable and weldable stainless steel.

This metal is commonly used in lieu of 300 series stainless steels in high temperature and low ph applications in food processing. For example, tomato juice will corrode 316L stainless steel at pasteurization temperatures of 210°F. AL-6XN will better resist this corrosion while still offering the beneficial properties of stainless steel.