A stainless heat-resistant self-shielded flux-cored wire for magnesium smelting reduction tank

Abstract

A stainless heat-proof self-protecting flux-cored wire for a magnesium smelting reduction tank belongs to the technical field of materials processing engineering. A normal stainless steel band 304L or common carbon steel serves as a coating layer, and alloys in a powder core are rutile, sodium carbonate, feldspar, compound fluorides, chromium, nickel, manganese, molybdenum, chromium nitride, aluminium-magnesium alloy, misch metal and iron power. Compared with a conventional stainless steel welding rod, the stainless heat-proof self-protecting flux-cored wire has the advantages that higher welding current can be used; higher welding speed can be realized; the production efficiency is improved; and the labor intensity is lowered; c. Compared with a conventional stainless steel submerged-arc welding solid wire, the stainless heat-proof self-protecting flux-cored wire has the advantages that all-position welding can be realized; the heat input is small; the slag detachability is good; and the manufacturing technique is simpler. A welded joint formed by using the stainless heat-proof self-protecting flux-cored wire provided by the invention has favorable heat resistance, oxidation resistance, vulcanization and corrosion resistance and high-temperature creep resistance compared with welded joints formed by welding the stainless steel welding rod and the stainless steel solid wire.

Description

technical field [0001] The invention belongs to the technical field of material processing engineering, and relates to a stainless heat-resistant self-protecting flux-cored welding wire, which is mainly used for welding reduction tanks for magnesium smelting. [0002] technical background [0003] Magnesium and magnesium alloys are currently the lightest structural materials in industrial applications. They have high specific strength, specific stiffness and good processing performance. In addition, they also have good thermal conductivity and electrical conductivity, damping and shock absorption, and electromagnetic shielding. Good and other characteristics, magnesium alloy is easy to process and shape, more importantly, it is easy to recycle and easy to degrade, so it is a very valuable green structural material. These characteristics of magnesium alloy make it widely used in electronic appliances, aerospace, national defense industry, automobile and other fields. [0004]...

AI Technical Summary

Problems solved by technology

When submerged arc welding wire is used, the heat input is large, and the slag after welding is easy to form a spinel structure, which sticks to the weld and is not easy to remove, resulting in low welding efficiency and high labor intensity

Due to the large welding current used by submerged arc welding wire, it is only suitable for flat welding and fillet welding positions. Although the connection between the head of the reducing tank and the tank body can be realized, it cannot complete the wall thickness of the small diameter tank and the thin wall of the large diameter tank. Welding of components

For some vertical welding positions and horizontal welding positions, submerged arc welding wire cannot be used, which restricts the application of submerged arc welding materials

[0009] Using the above-mentioned traditional austenitic stainless steel electrodes and submerged arc welding wires, because such welding materials do not match the material of the reduction tank body, the durability of the welded joints and the resistance to sulfidation corrosion are poor, so that the base metal of the reduction tank during use The welding seam has been corroded when it is intact, which leads to the scrapping of the reduction tank

In addition, because the welding joints of the reduction tank are subjected to high pressure, high temperature oxidation and gas erosion, it is easy to cause creep, thermoplastic deformation, cracking, sulfidation corrosion and peeling of the welded joints.

Especially when used in high temperature and sulfur-containing medium, the welding seam between the reduction tank body and the head is easy to peel off from the outside first, forming a dent or air leakage, resulting in a low service life of the reduction tank, even less than three months , has seriously affected the output of magnesium cans and the efficiency of magnesium smelting

[0010] The price of the reduction tank for magnesium smelting is high, and the number of replacements is large. In addition, in the production process, multiple reduction tanks are often working at the same time. If a single reduction tank has welding quality problems and cannot be repaired or replaced in time, it will lead to production stoppage and huge losses. economic loss

The lack of welding materials for high-quality, high-efficiency and automated magnesium-smelting reduction tanks severely restricts the application of magnesium-smelting reduction tanks

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