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Hardfacing and
Buildup |
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| Solid Wire | |
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| Hardfacing with solid wire utilizes the Gas Metal Arc Welding process. A shielding gas to protect the molten metal must be used and wire diameters available are generally 1/16" or less. Because a shielding gas is required, solid wires are best suited for "in shop" hardfacing applications. | |
| The range of alloys available is limited to those alloys that can be readily produced into solid wire form and to those alloys representing standard melting practice. Many highly desirable surfacing alloys are technically impossible or economically impractical to obtain. Thousands of pounds are required to produce a single chemistry. Those available fall into the following categories: | |
| Copper Base: | Aluminum Bronze, Tin Bronze, Silicon Bronze |
| Tool Steels: | Hot-working, Oil and Air Hardening, High speed, etc. |
| Low Alloy Steels: | 4130, 6150, 8620, etc. |
| Austenitic Stainless Steel, Martensitic Stainless, Nickel Base | |
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Cored Wires |
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| Cored wire enables the manufacture of hardfacing alloys to supply a wide range of chemistries in much smaller quantities than would normally be required to produce solid wire. Furthermore, alloys that are not readily available as solid wire, such as chromium or tungsten carbides, manganese build-ups and cobalt alloys, are easily produced as cored wires. | |
| In addition, cored hardfacing wire offers operational advantages over solid wire: | |
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Higher deposition rates at the same current levels |
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Ability to weld at lower heat settings |
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Improved arc characteristics |
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In some cases a better ability to weld on contaminated surfaces |
| Cored wire are available as metal-cored wires and as flux-cored wires. Both types are made by rolling thin strips into the form of a tube, and then, filling the tube with powder that contains metal powder (to produce metal-cored wire) or metal powder/flux combination (for flux-cored wire). | |