Tantalum loose lining

Corrosion-resistant metals and alloys, including stainless steels, nickel alloys, titanium, zirconium, and tantalum can be applied as linings or claddings to cheaper steel substrates. Most (>90%) are applied by roll bonding, but weld overlaying and explosive bonding are also used, as appropriate. Particularly expensive metals, such as tantalum, can be used as very thin ( 0.5 mm) loose linings. 

Loose lining. The loose-lined construction is used to make thick tantalum liners and was historically the first approach to a duplex system. The tantalum liner is manufactured separately and inserted into reactor vessels without bonding with the structural base metal. This loose-lined construction is the most economical and most widely used fabrication method throughout the entire industry. Liner thicknesses of 0.5 to 1 mm are satisfactory against corrosion. It is also possible to improve this technique by welding the liners to the base metal (i.e., weld overlay). Although economical, the loose-lined construction has some intrinsic drawbacks ... 

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