Haynes N-61 RTW description: HAYNES N61 RTW filler metal is used for the gas metal arc, gas tungsten arc and submerged arc welding of nickel 200 and 201 grades. The alloy has good resistance to alkalines and can also be used for the overlay and cladding of carbon and low alloy steels. Dissimilar welding applications include nickel 200 and 201 to carbon and stainless steels, copper-nickel alloys and other HAYNES and HASTELLOY grades. The RTW filler metal finish on the spooled wire promotes smooth feeding through welding equipment and reduced tip wear in contact tips.