UTP 6225 Al is a nickel base basic coated stick electrode of the E Ni 6704 (NiCr25Fe10Al3YC) type to EN ISO 14172 and E NiCrFe-12 to AWS A5.11. It joins high temperature nickel base alloys of similar composition, such as 2.4633 (NiCr25FeAlY) and 2.4851 (NiCr23Fe), and castings with a high nickel content.
The manufacturer states very good resistance of the deposit to oxidation and carburization and good creep rupture strength at service temperatures up to 1200 degrees C. Typical applications are steel tubes, rolls and baffles in furnaces, ethylene cracking tubes and muffles. Welding is done on DC with the electrode on the positive pole.
- Classification EN ISO 14172: E Ni 6704 (NiCr25Fe10Al3YC)
- AWS classification A5.11 / SFA-5.11: E NiCrFe-12 (mod.)
- Coating: basic
- Current: DC+
- Diameters: 2.5 / 3.2 / 4.0 mm
- Lengths: 250, 300 and 350 mm
The aluminium and yttrium additions build a protective layer in service, so do not grind the weld face back further than the procedure requires. Hold a short arc and lay narrow beads with a low interpass temperature, nickel alloys crack hot under high heat input. The preparation has to be clean: no grease residue and no markers containing sulfur. Dry the electrodes to the data sheet.
