DAIKOFCW 418

The weld metal based on Monel 400 alloy is characterized by high levels of Mn and Ti, a crucial element in preventing hot cracking and porosity. It is suitable for welding the 400 alloy and similar base materials, as well as other components in the Ni-Cu alloy system, such as pure nickel and cupronickel. Although welds with the K500 alloy are satisfactory, they don't match the strength of the precipitation-hardened alloy. Additionally, 400 alloy castings with a Si content of 1.5% or higher may exhibit crack susceptibility in the heat-affected zone (HAZ). In dissimilar joints between the 400 alloy and other alloys or steels, dilution with Fe (20-30%) or Cr (3-6%) can reduce the ductility of the weld metal near the fusion zone boundary. Direct welds on mild or low-alloy steels are satisfactory if dilution is controlled; however, for stainless steels and alloys with higher chromium content, the use of ERNiCr-3 wire is preferable and sometimes necessary. The 400 alloy offers a favorable combination of mechanical strength, thermal conductivity, and corrosion resistance in marine environments, inorganic salts, sulfuric and hydrofluoric acids, hydrogen fluoride, and alkalis. Typical applications include
heat exchangers, piping, vessels, and evaporators in offshore, marine, chemical, petrochemical, and power engineering sectors. No preheating is required, while interpass control is paramount.