| 摘要 |
Pd-Ni alloy electroplating bath contains a Ni salt, a Pd salt and at least 15 ppm I-ions. The bath pref. also contains a further conductive salt and an organic brightener. The pH is pref. 7-9 and the plating current density is pref. 10-150, esp. 25-100 A/sq.ft. Specifically, Pd salt is Pd(II) ammine chloride and the Ni salt is Ni ammine sulphate, Ni sulphate or Ni chloride. The further conductive salt is (NH4)2SO4 or NH4Cl and the brightener is Na vinyl sulphonate or quaternised pyridinium. The Pd salt is first purified through at least one recrystallisation cycle. Electroplating process is claimed, in which the Pd content of the plated coating varies by less than 10wt.% over the above applied current density range.
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