| 摘要 |
PURPOSE:To refine crystal grains of a welding metal, and to obtain a welding metal which does not become brittle even if it is exposed at a high temperature for many hours, by adding Si, Ti and Mg by a specific quantity into a coating agent of a welding rod. CONSTITUTION:This low-hydrogen-type coated electrode for low alloy heat resisting steel is obtained by coating a Cr -Mo compound steel core wire with a coating agent consisting of 45-60% total >= 1 kind metallic carbonate such as CaCO3, and BaCO3, etc., 15-20% metallic fluoride such as CaF2, and MgF2, etc., 3-4% Si, 1-3% Ti, 0.3-5% Mg, and mainly an arc stavilizer, a slag generating agent and a binder as its residual parts. As for Si, Ti, and Mg to be added into the coating agent, any of metallic powder of Si, Ti and Mg, an iron alloy such as Fe-Ti, and Fe-Si, etc., alloy powder such as Si-Ti, and Mg-Al, etc. are usable. |
