国家/地区 中国（4）
IPC部 C（4）
IPC大类 C23（4）
IPC小类 C23C（4）
IPC C25D003/56（4）
发明人 GUO C（3） LAI H（3） CHEN K（2）
公开年 2023（4）
申请年 2020（2） 
专利权人 GUANGZHOU UL.（3）

Plating layer structure for preparing chromium-free black conversion film, comprises metal substrate, and zinc-iron alloy plating layer sequentially from inside to outside on metal substrate.

LAI H, GUO C, LI X

Plating layer structure of zinc-nickel alloy plating layer without chromium passivation and hydroxyl graphene, has chromium-free passivation layer prepared by silane passivation agent.

LAI H, CHEN K, GUO C

Dull nickel-plated and graphene-enclosed plating structure for zinc alloy die-casting parts, has zinc-nickel alloy plating layer that is prepared from inside to outside sequentially zinc alloy base portion.

LAI H, CHEN K, GUO C

Preparing battery steel case coated with metal layer on the surface, comprises e.g. grinding surface of low-carbon steel strip, performing electroplating in nickel-iron plating solution, surface magnetron sputtering of cobalt, and electroplating in nickel-iron-cobalt-phosphorus plating solution.

LI J, ZHOU H