AL-6XN PLUS® alloy is an enhanced version of the standard AL-6XN® alloy. Both satisfy the composition requirements of UNS N08367, but the AL-6XN PLUS® alloy contains a greater concentration of the alloying elements (Cr, Mo, and N) which promote corrosion resistance.

Resistance to Localized Chloride Attack The relative pitting resistance of a stainless steel can be correlated to alloy composition using the Pitting Resistance Equivalent (PREN).

(PREN) = %Cr + 3.3 %Mo + 30 %N

Typically the AL-6XN alloy composition would have a PREN of about 47. By increasing the Cr, Mo, and N content of the alloy to near the maximum levels per-mitted by specification, the PREN can be increased.