Double-layer core-shell structure cast tungsten carbide particle weld wire and preparation method

Abstract

The invention provides a double-layer core-shell structure cast tungsten carbide particle weld wire and a preparation method. The weld wire comprises outer skin and a flux core. The flux core is formed in the manner that cast tungsten carbide is wrapped with carbon-rich sintered tungsten carbide, the carbon-rich sintered tungsten carbide is wrapped with nickel base layer core-shell structure tungsten carbide to form double-layer core-shell structure cast tungsten carbide particles, and the flux core is wrapped with the outer skin. The cast tungsten carbide particles are subjected to the surface carburizing technology, cast tungsten carbide, alloy powder and binder are mixed with carbon black and nickel powder and then heated at high temperature in vacuum, then heat preserving is carried out, the mixture is modified to form the double-layer core-shell structure, after modification, carbon-rich sintered tungsten carbide and a nickel base shell layer are formed on the exterior of the particles, the core-shell structure cast tungsten carbide particle flux core is obtained, and the flux core is wrapped with the outer skin to support the weld wire. According to the weld wire, while the tungsten carbide particles are refined, the cost is reduced effectively, the interface transition layer is additionally arranged, the hard tungsten carbide particles in a build-up welding layer do notfall off easily, and the hardness and the wear-resisting property of a cladding welding layer are effectively improved.

Description

technical field [0001] The invention belongs to the technical field of welding consumables, and in particular relates to a double-layer core-shell structure casting tungsten carbide particle welding wire and a preparation method thereof. Background technique [0002] Surfacing repair of chemical equipment and various mechanical equipment wear parts, such as metallurgical machinery, mining machinery, turnouts, jaw plates, buckets, shovel teeth, engineering quarry ships and other brick machine reamers, spirals, mixer blades, fans Improving the performance and service life of blades, mineral processing machinery, engineering machinery, and building materials machinery is an urgent need to be solved. At present, cast tungsten carbide particles are generally used to strengthen iron-based composite materials in wear-resistant composite materials that have been studied more. This is because cast tungsten carbide particles can be completely wetted with high-temperature molten iron, ...

AI Technical Summary

Problems solved by technology

However, two problems were found in the research. First, sintered tungsten carbide is mainly composed of WC, which has high purity but high cost, while the cost of cast tungsten carbide is relatively low, which mainly contains WC and W 2 C

Compared with single-phase WC particles, WC / W 2 C has higher hardness and toughness and is cheaper, but the decomposition of particles is more serious, which affects the wear resistance of the surfacing layer

The main disadvantage of tungsten carbide is its poor resistance to high-temperature oxidation. It is severely oxidized in the air at 500-800 °C, and it is easily decomposed into W by strong heat in an oxidizing atmosphere. 2 C and carbon, the so-called "loss of carbon"

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