Development Of High Temperature Wear Resistance Non-slag Electrode For Hard-facing

A kind of nickel-base non-slag hard-facing electrode of resistance to high temperature wear is studied, because nickel-base alloys have an excellent high temperature synthetic ability, and there is nearly no this kind of hard-facing electrode in present market. The developed electrode has a little soot during welding, and the soot does very little harm to workers' health; since there is no slag on the bead after welding, it can weld successively multi-pass and needn't chip slag, what's more, its price is much cheaper than the cobalt-base hard-facing electrode, and the resistance to high temperature abilities of the deposit are excellent. That the electrode is developed successfully will change the present situation: some welding work-pieces which are served in the high temperature condition long time needn't mainly be made or repaired with the precious cobalt-base electrode any more, at the same time, the electrode also solves the problems that the common hard-facing electrode gives off large soot during welding and detaches slag very difficultly (if the slag isn't chipped clearly, it will affect the welding quality.). Therefore, the developed electrode improves working condition and efficiency, it meets with the market's needs. This paper ascertained the coating composition by many tests, used a simple and convenient method to analyze qualitatively the resistance to crack ability of the deposit and the hard-facing alloy self-harden ability; analyzed the microstructure of the deposited metal in as-welded and that after austenite stabilized aging treatment, and the microstructure of both are heated 650 ℃ and preserved 24 hours respectively with the optical microscope, the scanning electron microscope and the X-ray diffraction. The effects of the austenite structure stabilizing heat treatment on the work-pieces mechanistic ability are studied primarily when it is served in the high temperature condition longtime, and the function of the elements in the hard-facing alloy including C, Cr, Ni, Ti, W, Mo, V, B, Re, Nb, etc., and the effects of these alloy elements on the hardness and on the microstructure are also analyzed in this paper. Finally, the high temperature abilities of the hard-facing alloys are examined by the room hardness test, the resistance to high temperature wearing bi-metals test, the resistance to thermal fatigue test and the resistance to high temperature oxide test.