| 摘要 |
1514816 Electro-plating nickel-iron alloy OXY METAL INDUSTRIES CORP 23 May 1975 [3 March 1975] 22803/75 Heading C7B A metallic substrate, e.g. a Cu, brass or steel panel preferably electro-plated with a Cu layer (e.g. 10 or 15Ám thick), is electro-plated first with at least one Ni-Fe alloy first layer (e.g. at least 10Ám thick) having a relatively high Fe content of 15 to 40%, then with at least one second layer of Ni-Fe alloy (e.g. 2.5 to 10Ám thick) having a relatively lower Fe content of 5 to 14%. The uppermost Ni-Fe alloy layer may be electro-plated with a Ni layer (e.g. 3Ám thick) preferably microcracked and having inorganic particle inclusions therein, in turn electro-plated with a microdiscontinuous, preferably micro-cracked Cr layer (e.g. 0.25 to 0.4Ám thick). The Ni-Fe alloy composite may be electro-deposited from a plurality of solutions or the same solution containing one or more salts of Ni and Fe, e.g. nickel and ferrous sulphate, chloride, sulphamate and/or fluoroborate, with complexing agents such as hydroxy C 2-8 aliphatic carboxylic acids e.g. citric, malic, glutaric, gluconic, muconic, glutamic, glucoheptonic, glycolic or aspartic acid, at pH 2.5 to 5.5 and C.D. 10 to 70 ASF. With the same solution, the reduction of Fe content can be achieved by reducing in stages air agitation (for high Fe content) to nil (for lower Fe content). Soluble anodes of Fe or Ni-Fe alloy may be used. S-O compound or acetylenic Ni brighteners or organic sulphides may be used in the plating bath. |
