Sulfuric acid corrosion-resistant pure austenitic stainless steel electrode with high nickel and copper content and low thermal crack sensitivity and preparation method

Abstract

The invention discloses a sulfuric acid corrosion-resistant pure austenitic stainless steel electrode with high nickel and copper content and low thermal crack sensitivity, which is composed of a nickel-chromium-molybdenum-copper-iron alloy welding core and a coating covering the surface of the welding core. The content is: 7-13 parts by weight of rutile powder, 4-8 parts by weight of marble powder, 1.0-4.0 parts by weight of fluorite powder, 1.5-4.0 parts by weight of mica powder, 1.5-3.0 parts by weight of potassium feldspar powder, 2-3 parts by weight of electrolytic manganese parts by weight, 0.25-0.6 parts by weight of niobium powder, 1.0-2.0 parts by weight of metallic chromium powder, 0.2-0.6 parts by weight of ferromolybdenum powder, 0.1-0.5 parts by weight of soda ash and 0.1-0.5 parts by weight of sodium alginate. Compared with the existing ones, the electrode deposited metal of the invention has excellent mechanical properties, strong thermal crack resistance and excellent intergranular corrosion resistance.

Description

technical field [0001] The invention belongs to the technical field of welding materials, and in particular relates to a sulfuric acid corrosion-resistant pure austenitic stainless steel electrode with high nickel and copper content and low heat crack sensitivity and a production method thereof. Background technique [0002] The regenerated flue gas produced by the catalytic cracking unit in the refinery contains a large amount of sulfur dioxide (SO2), nitrogen oxides (NOx) and catalyst dust. An effective way to reduce flue gas SO2, NOx and catalyst dust emissions is to use flue gas desulfurization and denitrification technology. Flue gas scrubber is the key equipment of this technology. The inlet temperature of the flue gas scrubber is about 200°C. The high-temperature flue gas combines with quenched atomized water to form sulfuric acid and nitric acid. The dry-wet interface that is most prone to acid corrosion at the inlet section of the scrubber and the flue gas distribut...

AI Technical Summary

Problems solved by technology

At present, ENiCrMo-3 electrode is mostly used for Alloy20 alloy welding. The Ni element content of the welding material is higher than 50%, which is expensive, and the content of Ni, Cu, and Mo elements in the base metal and the deposited metal is quite different. Diffusion, microstructure and properties change. For this reason, a homogeneous welding consumable that matches the Alloy20 alloy composition is specially developed. The developed electrode deposited metal has excellent mechanical properties, strong thermal crack resistance, and excellent intergranular corrosion resistance.