Abstract
The objective of this study was to investigate the weldability of a new laminated material based on nichrome powder alloy using tungsten inert gas welding. Results revealed that nichrome-laminated powder alloy could be successfully joined by TIG welding. Two typical fusion zones were formed between different layers (Ni cover layer and nichrome base layer) and weld metal. Moreover, fusion zone of nichrome powder alloy was jagged due to the presented porosity. Between nichrome powder alloy and the filler metal, elements diffusion was obvious and a transition zone about 80-85 μm was formed. Microhardness near the fusion zone of nichrome base layer side (210-250 MPa) is higher than that near the fusion zone of Ni cover layer (190-210 MPa). Phase constitutions of the welded joint consisted mainly of γ-Fe, δ-ferrite and γ-Ni (Fe, Cr). Furthermore, co-existing microstructure of γ austenite and a small amount of δ ferrite was observed in the weld seam.

Key words
powder alloy, tungsten inert gas welding, fusion zone, fine structure

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