DE1953769C - Covered electrode for welding cast iron pieces with spheroidal graphite - Google Patents

Claims (1)

1 2 The invention relates to a coated elec- trium or partially by equivalent amounts of strontium trode for welding castings made of cast iron and / or barium must be replaced, as these too spheroidal graphite iron. because of their higher boiling point than spheroidal graphite With the ever increasing areas of application the bildner are suitable for welding. The Si content The material cast iron with spheroidal graphite was required, 5 causes the formation of a pearl in the weld seam. also the welding possibilities with the help of table structure and prevents the formation of to add another type of electrode. Cementite. Welding electrodes have already been proposed. The solution according to the invention deviates from the sideways, which are mostly taken from the expensive alloy. One has so far made of nickel. io tried to solve the problem with expensive alloy additives Other suggestions see the cladding of the loosening or the electrode carbon in it Graphite electrode, which makes it difficult to introduce systematically, while the problem of brings it about that this carbon conversion of this carbon, introduced as graphite, existed in spherical form, lenstoff later in the weld seam as spheroidal graphite The invention solves the problem in a simple way should be present. 15 way by not putting any carbon over the electrode In the German Auslegeschrift 1 242 986 is introduced, but rather the carbon from which an additional alloy is described, which diffuses into the weld seam to the large surrounding material, part of rare earth metals as well as calcium, iron and the coating consists of soft iron and silicon. In the case of existing core wire Ca-Si, this additional alloy should be added in sufficient quantities to the steel production and also to the order quantity. Expensive alloy additives such as Ni welding, the removal of oxygen and the like can be dispensed with.
Sulfur from molten iron and steel causes the arc welding with this electrode, at the same time cleaning the deposited weld, is positively influenced by preheating to about 350 ° C, as is the case with carbon steel with a high carbon steel. Subsequent heat treatment will cause graphite to be deposited. An 25 is not required, but may be used for electrodes for strength component. Welding cast iron castings with spherical With the electrode is a supplement to the derzeigraphit is not intended and would be given for this term range. In workpieces which, because of the insufficient accuracy for a soft iron electrode according to the invention, are welded with the graphite in the form of spheroidal graphite 30, cannot be suitable without great effort. In addition, the rare earths achieve higher strengths,
metals relatively expensive alloying elements. The present invention has the object of reasons to develop a welding electrode, which 1. Covered electrode for welding Strength welds of castings made of castings - 35 castings made of cast iron with spheroidal graphite, d a - spheroidal graphite iron is allowed and at the same time Ni-free is characterized by the fact that it consists of one is. The weld seam should therefore have the same material core wire made of soft iron and a sheath have properties like the castings. which is free of free carbon The solution to this problem assumes that and at least 7% calcium in the form of a No free carbon was added through the electrode. Calcium-silicon alloy with 35% calcium may be brought and sees one for this purpose. Core wire made of soft iron and a sheath in front, 2. Sheathed electrode according to claim 1, there- which is free of free carbon and is at least characterized in that calcium wholly or 7%> Calcium in the form of a calcium-silicon alloy, partly through equivalent amounts of strontium with 35% calcium. Calcium can be completely substituted for 45 and / or barium.