Microstructure and wear mechanism change by Nb added in slag free self-shielded flux cored wire. (November 2015)

• Record Type: Journal Article
• Authors: Liu, D. S.; Wei, Y. H.; Liu, R. P.
• Is Part Of: Science and technology of welding & joining. Volume 20:Number 8(2015:Nov.)
• Page Start: 693
• Page End: 701
• Publication Date: 2015-11
• Subjects: Welding -- Periodicals; Joints (Engineering) -- Periodicals; Surfaces (Technology) -- Periodicals; 671.52
• DOI: 10.1179/1362171815Y.0000000056
• Languages: German
• ISSNs: 1743-2936

Abstract

<abstract> <title> <x content-type="archive" xml:space="preserve">Abstract</x> </title> <p>The iron based hardfacing alloys were produced using slag free self-shielded flux cored wires with varying niobium contents. The results show that NbC acted as the nucleus of primary M₇(C, B)₃ (M = Cr, Fe mainly) carbides and decreased the amount of M₇(C, B)₃ carbides when niobium was added into the alloys. When 18 wt-%Fe–Nb (60 wt-%Nb) was added, the microstructure of hardfacing alloy transformed from hypereutectic structure to a eutectic one due to the formation of NbC, which consumed a mass of carbon. The microstructure changed into a hypoeutectic structure when the Fe–Nb content was up to 24 wt-%. With the increase in Fe–Nb content, the main abrasive wear mechanism changed from microcracking to microcutting and microploughing due to the formation of NbC and the reduction of primary M₇(C, B)₃ carbides. The wear loss of the alloy with 18 wt-%Fe–Nb addition was the smallest among all the alloys.</p> </abstract>