In the welding industry, often use a variety of alloy powder. They are used for brazing various pure metals and alloy powders for thermal spraying of iron, nickel, cobalt-based alloy powder and other types for tubular welding wire alloy powder.
Thermal spraying is a surface enhancement technology, China has been the focus of the promotion of new technology projects. It uses electric arc, plasma arc, gas, a form of oxygen, heat, metal or non-metallic material is heated to a molten or semi-molten state, and in the high-speed air flow under the action of the atomized into fine droplets or high-temperature particles to high speed jet flight to the treated surface to form a solid cover, so that the workpiece surface to obtain different hardness, wear resistance, corrosion resistance, heat resistance, oxidation resistance, thermal insulation, insulation, electrical conductivity, sealing, sterilization, anti-microwave radiation, and various other special physical and chemical properties. It can be equipment maintenance repair old, so that scrapped parts "revived"; can also manufacture the new product and pre-intensive protection to "longevity."
In the thermal spray powder coating materials occupy very important position. Thermal spray powders include nickel-based alloys, iron-and cobalt-based alloy powder, according to the hardness of different coatings were applied to mechanical parts repair and protection. Thermal spray technology after years of development in the country has formed a complete system of equipment research and production, currently engaged in this work more than 20 units, can produce various types of oxyacetylene flame spraying equipment, spraying molten equipment, arc spraying equipment, manganese powder complete sets of plasma spraying equipment, spray equipment, a variety of special equipment and so on. Thermal spray alloy powder as a necessity for thermal spraying operations, the country will also have more than a dozen companies in the production.
Nickel-based self-fluxing nickel-based alloy powder as matrix elements, add chromium, boron, silicon, carbon, copper, molybdenum, and other elements, the low melting point alloy powder, a good self-insoluble, with corrosion, wear, heat, antioxidant properties, is currently the most widely used self-fluxing alloy powder spray. Iron-based alloy powder is divided into two types of stainless steel, nickel and chromium containing more elements; the other is the high-chromium cast iron type, with higher chromium and carbon. Co-based self-fluxing alloy powder is cobalt matrix elements, adding chromium, tungsten, nickel, boron powder, silicon and other elements, has a superior high temperature performance, good red hardness, wear resistance and oxidation resistance. Cu-based self-fluxing alloy powder is a copper matrix, add the appropriate amount of nickel, chromium, boron, silicon, manganese and other elements, such alloy powder with good mechanical properties, plasticity, easy processing, good corrosion resistance, and low coefficient of friction.
In addition to the alloy powder for thermal spraying, the production of tubular welding wire alloy powder consumption is increasing rapidly. Although the advent of tubular welding wire has been sixty years of history, but is still widely used in the past decade to do, mainly because its production process and filler tube immature and imperfect. In particular, tube filler, when two or more kinds of powder on the proportion of similar cases, silicon powder the use of mechanical mixing is still regarded as an economic and practical milling process, so far, there are still many manufacturers in use. But when two or more of the powder in the proportion of the difference is large, the use of mechanical mixing is difficult to mix evenly, there is a wire made of tubular powder segregation, which causes element segregation, weld quality on the negative impact . To overcome this problem, it was designed to do the test, use a mechanical mixture of metal powder and water atomized alloy powder produced two padding powder, made into a tubular welding wire, welding performance tests. The results show that the use of atomized alloy powder filled tubular wire, reliable, easy operation, cladding layer composition uniformity, low hydrogen content, stomatal resistance ability. Therefore, the use would be a good solution alloy powder wire segregation tubular way, the domestic manufacturers have adopted this technology.
Tubular wire is likely to be the major future development of welding consumables, metal powder supplier China has just started, regardless of quality, variety, quantity compared with other countries, have a larger gap. Tube made of wire can be used with a high carbon steel alloy flux-cored wire, such as heat-resistant steel, cold steel, weathering steel, stainless steel pipe with a special flux-cored wire. This is compared in terms of solid welding wire and electrodes have greater advantages. Source: