Selection and use of nickel and nickel alloy welding rod

(1) The selection principles of nickel and nickel alloy electrode of nickel and nickel Welding Alloysis selected according to the welded base metal alloy grades, chemical composition and the use of environmental conditions. The electrode of the main chemical composition of deposited metal to be close to the main component of the base metal to ensure that the properties of welded joints and base metal. But taking into account the electrode alloy loss in the arc in the electrode should also contain some other elements to improve weld performance or welding performance.
Electrode using the same ingredients to reach the design requirements or there is no suitable similar alloy composition of the electrode, it is recommended that selection of the electrode of the high performance level, to ensure that the use of properties of the weld is not less than the base metal.
(2) the use of nickel and nickel alloy electrode Notes
① base metal preparation: oil, paint, dust, dirt, carefully clear the surface of the base metal before welding.
② In order to prevent the pores, the use of short-arc welding.
③ the use of smaller welding current, welding without preheating, maintaining low interpass temperature (<150 ° C), in order to avoid the overheating of the base metal.
④ Tungsten Welding Electrodessmaller swings on both sides of the weld bead to stay a little longer, to facilitate stomatal and weld slag surfaced.
The ⑤ Crater attention to fill the crater, in order to avoid cracks in the crater.
⑥ nickel and nickel alloy microstructure of austenite, strong tendency of hot cracking in welding of fillet weld, the weld was convex shape, so you can better prevent heat cracks.