Hello fellow experts,
I've recently taken on a project that involves performing a zirconium overlay using ERZr-2 on 316L stainless steel with the GTAW process. As many of you know, zirconium is an active material that poses unique challenges. It readily forms reactive metallic particles that can lead to cracking, and overheating can cause oxidation. This oxidation may melt and mix into the weld pool at the same temperature as the zirconium itself, further compromising weld quality.
To mitigate these issues, we initially used ERNi-1 (pure nickel) as a diffusion barrier or buffer layer, followed by a zirconium overlay. However, this resulted in crystallized cracking in the weld metal (see attached photos). The welder also described a "gummy melting" behavior, which ultimately led to a lack of fusion between the zirconium and the buffer.
We then tried using ERTi-1 (commercially pure titanium) as the buffer layer, but observed the same issues. Even when attempting a combination of one layer of nickel followed by one layer of titanium before the Zr overlay, we were unsuccessful.
Has anyone here worked on a similar project involving zirconium overlays on stainless steel? If so, I would greatly appreciate any insights, tips, or recommendations regarding buffer layer selection, welding parameters, or techniques that helped ensure metallurgical compatibility and sound fusion.
Any guidance or shared experience would be immensely appreciated.View attachment IMG_6712.jpg
I've recently taken on a project that involves performing a zirconium overlay using ERZr-2 on 316L stainless steel with the GTAW process. As many of you know, zirconium is an active material that poses unique challenges. It readily forms reactive metallic particles that can lead to cracking, and overheating can cause oxidation. This oxidation may melt and mix into the weld pool at the same temperature as the zirconium itself, further compromising weld quality.
To mitigate these issues, we initially used ERNi-1 (pure nickel) as a diffusion barrier or buffer layer, followed by a zirconium overlay. However, this resulted in crystallized cracking in the weld metal (see attached photos). The welder also described a "gummy melting" behavior, which ultimately led to a lack of fusion between the zirconium and the buffer.
We then tried using ERTi-1 (commercially pure titanium) as the buffer layer, but observed the same issues. Even when attempting a combination of one layer of nickel followed by one layer of titanium before the Zr overlay, we were unsuccessful.
Has anyone here worked on a similar project involving zirconium overlays on stainless steel? If so, I would greatly appreciate any insights, tips, or recommendations regarding buffer layer selection, welding parameters, or techniques that helped ensure metallurgical compatibility and sound fusion.
Any guidance or shared experience would be immensely appreciated.View attachment IMG_6712.jpg
