Titanium descaling

Variety of Scale. Another factor that contributes appreciably to titanium descaling problems is the wide variety of scale encountered, including scale formed by annealing, forging, solution treating, stress relieving, ex-... 

An important iadustrial use of NaH involves its in situ formation ia molten NaOH or ia fused eutectic salt baths. At concentrations of 1—2% NaH, these compositions are powerful reducing systems for metal salts and oxides (5). They have been used industrially for descaling metals such as high alloy steels, titanium, zirconium, etc. 

Resolution heat treatment (re-annealing) may be used to relieve stress if the welded assembly is amenable to such treatment. All titanium stufaces should be free of dirt, fingerprints, grease, and residues before stress relieving. Contaminated surface metal must be removed firom the entire weldment by machining or descaling and pickling to remove 0.025 and 0.05 mm (0.001 to 0.002 in.) per surface. 

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