Experimental investigation on high-temperature tensile behavior of cold metal transfer pulse multi-control welding of Inconel 617 alloy

Abstract

To improve the efficiency of the advanced steam power plants, both the pressure and temperature of the steam are increased. The Inconel 617 alloys are a candidate material for these applications. The microstructural features and tensile characteristics of welded joints made using the cold metal transfer (CMT) plus pulse multi-control (PMC) by varying the wire feed speed (8.9, 9.4, and 9.9 m/min) at room and high temperatures (650 °C, 700 °C, and 750 °C) are examined. An optical microscope (OM) and Field emission scanning electron microscope (FESEM) were used to examine the microstructure and fracture surfaces of the alloy. The mechanism of strengthening and the effects of precipitates on tensile strength and % elongation in both Base metal (BM) and weld bead are discussed in detail. The mechanical behavior was analyzed in terms of impact strength and bending strength in detail by varying the wire feed speed (WFS). Indications for porosity and cracks were not reported in the X-ray radiography test. The macrographs revealed that bead width, penetration depth, the metal deposited on the weld, and HAZ are in direct proportion with wire feed speed. Bend test results showed that the weld joints exhibit good ductility without cracks.