( 1 ) Nickel and nickel alloy electrode selection principle of nickel and nickel alloy electrode mainly based on the base material being welded alloy grades , chemical composition and use of environmental and other conditions used . Deposited metal electrode , the main chemical ingredient should be the main component of the base metal to be close in order to ensure the performance of welded joints and base metal considerably . However, considering the alloy in the arc welding losses, welding should also contain other Cast Iron Welding Electrode elements , in order to improve performance or seam welding performance.If you use the same ingredients electrode design requirements or did not reach a similar alloy composition suitable electrode , then the recommended use of high-performance one level electrode, in order to ensure that the weld performance is not less than the base metal .( 2 ) Nickel and nickel alloy electrode precautions for use① base metal preparation: before welding the base metal surface should be carefully cleared of oil , paint , dust and other dirt .② In order to prevent the holes, using a short -arc welding.③ The small welding current, welding without preheating , interpass temperature kept low (<150 ℃), in order to avoid overheating of the base material .④ welding rod swings to small, stay a little longer bead on both sides , in order to facilitate the pores and slag floats .Note ⑤ crater fill the crater to avoid crater cracks .⑥ nickel and nickel alloy microstructure of austenite , has a strong tendency to hot cracking in the weld fillet weld , the weld was required convex , so you can better prevent heat cracks .