Contamination by active gases such as o2, n2, and h2 can have considerable effects on zirconium's mechanical, chemical, and thermal characteristics. 2. All foreign material must be removed from the joint and the filler wire before welding can begin. Inert gas shielding must be used to protect the metal surfaces until the weld metal cools to a temperature below 3150C, which is its melting point at 1,8350C. Zirconium welding is performed using EBW and GTAW techniques, both of which require an electron beam. There is no need for environmental protection because EBW is conducted in a vacuum.
For main, secondary and backup shielding and purging, welding-grade argon ie 10 ppm other gases (99.999 percent argon) is required. Welds are shielded by arc stability provided by argon since it is heavier than air. Backup shielding and purging may also be done with argon and argon/helium mixes, with helium's low density effectively purging blind gaps. The dew point of gas should not exceed -510C. Fusion welding is required in a large number of these applications, but it must be done with caution to guarantee that weld quality is consistent. All traditional welding procedures may be applied, and the fundamental technical features have long been established. However, contamination must be avoided since zirconium alloys are particularly prone to cracking and porosity if the welding environment is not carefully regulated. Prior to welding, machining or aggressive stainless steel wire brushing is required, followed by complete degreasing with a suitable solvent, with welding taking place within eight hours to minimise the danger of contamination.
Standard Specification For zirconium WELDING CONSUMABLES :
|Form :||MIG spools, TIG cut lengths, Reels and Coils|
|Type Of Welding :||Inert Gas Welding|
|Standard TIG straight lengths are available :||36” (914 mm) or 39” (1000 mm) lengths. Other lengths available upon request.|