Method of welding electrode for vacuum consumable arc-melting

Abstract

The invention discloses a welding method for an electrode used for consumable vacuum arc melting. The method relates to: lathing two ends of an upper part electrode and a lower part electrode that are butt welded; processing the welding end of the upper part electrode into a lug boss; processing the welding end of the lower part electrode into a groove; arranging the processed upper part electrode into a consumable vacuum arc furnace with the lug boss facing downwards; arranging the lower part electrode in a pot in the consumable vacuum arc furnace and locating with the groove surface facing upwards; arranging an arc striking material on a salient part at the core part of the lower part electrode, sealing the consumable vacuum arc furnace and welding after cacuumizing. The invention has a simple structure and a good centering effect between the upper part electrode and the lower part electrode; and when welding, an alloy liquor filling groove melted by arc starting can not overflow to the circle surface of the electrode, thus avoiding crack, 'nuble' or scrap rubber at the location of a welding line; thereby ensuring the welding quality. The welding contact area is large and can not generate rosin joint; the electrode after welded is firm and can avoid falling off when melting.

Description

technical field [0001] The invention relates to an electrode welding method, in particular to an electrode welding method for refractory metal alloy vacuum consumable arc melting. Background technique [0002] With the continuous expansion of the scope of use of refractory metals (mainly molybdenum alloy TZM and niobium alloy C-103, Nb521), the purity of the alloy and the size of the ingot are required to be increased. These requirements must be met without making the alloy ingot The grain size is too large, vacuum arc melting is a very good ingot preparation technology. With the continuous application of this technology, there is also a problem that is often encountered. Since the molybdenum alloy matrix is ​​a brittle material, the high degree of alloying of the niobium alloy makes the alloy brittle. When two planes are used for self-welding, often There are problems of weld metal brittle cracks, few welding spots, and metal solidification (nodules) flowing down the elect...

AI Technical Summary

Problems solved by technology

[0003] 1. If the electrode splits suddenly before arc melting, falls to the bottom pad and then dumps, the equipment will be subject to a great impact, and the dropped electrode may damage the copper crucible;

[0004] 2. If it falls during the arc melting process, the arc starting condition will be met between the electrode and the crucible at the moment of falling, which will cause the arc to crawl up 300-400mm along the ingot, and a large amount of metal will be lifted by the arc. After cooling On the upper end of the smelted ingot and around the circumference of the electrode, a solidified metal wall of varying heights, thin at the high and thick at the low, is formed. The splashed molten metal falls on the copper crucible and causes point-shaped pits.

[0005] It can be seen that the above two situations will bring great losses to equipment and materials.

Images