Homogeneous electric welding rod/flame welding wire for welding gray cast iron and ductile cast-iron

Abstract

The invention discloses a welding wire and welding rod core used in welding gray cast iron, which is formed by following weight proportion: C at 3.6%-4.0%, Si at 3.6%-4.6%, Mn at 0.2%-0.4%, S<0.05 %, P<0.1%, Ca<2%, Ni at 0.2%-1.2%, Ti at 0.3%-.8%, Al at 0.1%-0.5%, Bi at 0.03%-0.06%, Ba at 0.01%-0.03%, Ce at 0.01%-0.04% and RE at 0.01%-0.03% while the other is Fe. And the welding wire and welding rod core used in welding nodular graphite cast iron, which is formed by following weight proportion: C at 3.6%-4.2%, Si at 3.6%-4.6%, Mn at 0.2%-0.4%, S<0.03 %, P<0.06%, Ca<4%, Ni at 0.2%-2%, Ti at 0.3%-1.2%, Cu at 0.2%-0.8%, Al at 0.1%-0.5%, Bi at 0.01%-0.06%, Mg at 0.02%-0.03%, Ba at 0.01%-0.03%, Ce at 0.01%-0.04% and RE at 0.01%-0.03% while the other is Fe. The invention can realize the welding rod cooling welding or lower temperature welding, while the component, organization, property and color of welding line are the same as casting, with better process-ability and crack resistance.

Description

technical field [0001] The invention belongs to the technical field of welding materials, in particular to cast iron homogeneous electric welding electrodes and gas welding wires suitable for welding gray cast iron and nodular cast iron. Background technique [0002] As special welding materials, cast iron electrodes and wires are indispensable in engineering fields such as casting iron welding and defect repair. Due to the high content of impurities such as sulfur and phosphorus in cast iron, low strength, and poor plasticity, its inherent solidification characteristics determine that during the welding repair process of cast iron, white spots and cracks are prone to occur in the welding repair area, especially under cold welding conditions. And the crack tendency is greater, which seriously affects the machining performance and service performance of castings. [0003] Use cast iron electrodes coated with graphitized coating on non-cast iron cores for cast iron welding, s...

AI Technical Summary

Problems solved by technology

Due to the high content of impurities such as sulfur and phosphorus in cast iron, low strength, and poor plasticity, its inherent solidification characteristics determine that during the welding repair process of cast iron, white spots and cracks are prone to occur in the welding repair area, especially under cold welding conditions. And the crack tendency is greater, which seriously affects the machining performance and service performance of castings

[0003] Use cast iron electrodes coated with graphitized coating on non-cast iron cores for cast iron welding, such as Z208 (low carbon steel core) electrodes, Z308 (pure nickel core) electrodes, Z408 (nickel iron core) electrodes, etc., although to a certain extent Reduce white spots and cracks, but because the composition, structure, performance and color of the weld do not match the casting, the crack resistance is poor, and it cannot meet the comprehensive performance requirements of repairs such as color consistency and performance matching.

[0004] Applying welding materials of the same quality as cast iron, such as commercially available Z248 and Z238 electrodes, and adopting a hot welding process are effective measures to overcome the above defects, but the preheating method of hot welding is complicated, energy consumption is large, the production cycle is long, and labor intensity is high , will undoubtedly increase the production cost of castings

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