Hobart SubCOR SL P91 description: SubCOR SL P91 is a seamless, low-alloy, cored wire for submerged-arc welding. In addition to Niobium and Vanadium, SubCOR SL P91 has a nominal 9% chromium/1% molybdenum weld deposit, and is suitable for joining creep-resistant steels having a similar composition. SubCOR™ SL P91 exhibits good creep and scale resistance at temperatures up to 1100F (600C).