AL-6XN (UNS designation N08367) is a type of weldable stainless steel that consist of an alloy of nickel (24%), chromium (22%) and molybdenum (6.3%) with other trace elements such as nitrogen.

The high nickel and molybdenum 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 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.^[1]

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 (100 °C). AL-6XN will better resist this corrosion while still offering the beneficial properties of stainless steel.

AL-6XN chemistry^[2][edit]

AL-6XN markets^[2][edit]

• Chemical processing
• Oil and gas
• Medical – sterilization
• Power generation

AL-6XN applications^[2][edit]

• Desalination
• Water piping systems
• Transformer cases in marine environments
• Food processing equipment
• FGD scrubbers
• Reverse osmosis
• Heat exchangers

AL-6XN specifications^[2][edit]

• ASME SA : 182, 240, 249, 312, 479
• ASME SB : 366, 462, 564, 675, 676, 688, 691
• ASTM A : 182, 240, 249, 312, 479
• ASTM B : 366, 462, 472, 564, 675, 676, 688, 691, 804
• NACE : MR0175
• UNS : N08367