Electron beam butt welding of Cu-Cr-Zr alloy plates: Experimental investigations, studies on metallurgical and mechanical properties

Studies related to butt welding of precipitation hardened (PH) Cu-Cr-Zr alloy plates using electron beam were carried out. Significant reductions in strength and microhardness were observed for all no-aged electron beam welded joints. The microstructural studies of fusion zone of the welded samples were analyzed in order to understand the reasons behind their loss of micro-hardness and tensile strength. Precipitation behaviors of different zones were also studied using X-ray Diffraction (XRD), Energy Dispersive X-ray Spectrometry (EDS) and transmission electron microscopy (TEM). All the metallurgical studies indicated reduction of precipitate and intermetallic density in the fusion zone of the weld. In addition to that, the effects of process parameters, namely accelerating voltage, beam current and welding speed, were studied on the responses, such as micro-hardness and tensile strength of the welded sample. A set of optimal input parameters was also determined in order to obtain the maximum microhardness and tensile strength. Fractographic analyses of the joints were carried out to study the failure behavior of the butt-welded specimens.