Гальваническое покрытие для финишной обработки поверхностей (хром, никель, цинк)

Нанесение тонких металлических покрытий для защиты и декора

Metallurgy & Metal Processing Global Industrial Scale $15 billion

Обзор

Electroplating deposits a thin layer of metal onto a conductive substrate using electrolysis, providing corrosion protection, wear resistance, and decorative finish. The most common electroplating processes are zinc plating (corrosion protection for steel), nickel plating (decorative and functional), and chromium plating (hardness and aesthetics). The automotive, electronics, aerospace, and jewelry industries are major consumers. Decorative chrome plating on car bumpers and bathroom fixtures uses only 0.25-0.50 microns of chromium over 10-30 microns of nickel.

Химический процесс

The workpiece is cleaned (alkaline soak clean, acid pickle, electrocleaning) and racked or placed in a barrel. It is immersed in a plating bath containing dissolved metal salt, complexing agents, brighteners, and levelers. DC current deposits metal ions as a coherent metal coating. For decorative chrome: a copper strike (1-2 microns), then nickel (10-30 microns from Watts bath), then chromium (0.25-0.50 microns from chromic acid bath). Bath composition and current density control deposit quality.

Ni²⁺ + 2e⁻ → Ni(s) (nickel cathodic deposition, Watts bath)
CrO₃ + 6H⁺ + 6e⁻ → Cr(s) + 3H₂O (chromium deposition from hexavalent chromium)
Zn²⁺ + 2e⁻ → Zn(s) (zinc plating for corrosion protection)

Сырьё

  • Nickel sulfate (NiSO₄) + nickel chloride (NiCl₂) — Nickel refining (Nickel plating bath (Watts bath: 250 g/L NiSO₄, 45 g/L NiCl₂, 35 g/L H₃BO₃))
  • Chromic acid (CrO₃) — Oxidation of Cr₂O₃ (Chromium plating bath (250 g/L CrO₃, 2.5 g/L H₂SO₄))
  • Zinc chloride or zinc sulfate — Zinc refining (Zinc plating bath)

Конечные продукты

  • Electroplated metal components — Automotive, electronics, aerospace, bathroom fixtures, jewelry (0.1-100+ micron coating thickness depending on application)
<path stroke-linecap="round" stroke-linejoin="round" d="M12 9v3.75m-9.303 3.376c-.866 1.5.217 3.374 1.948 3.374h14.71c1.73 0 2.813-1.874 1.948-3.374L13.949 3.378c-.866-1.5-3.032-1.5-3.898 0L2.697 16.126zM12 15.75h.007v.008H12v-.008z" />

Environmental Impact

Hexavalent chromium (Cr(VI)) used in traditional chrome plating is a known carcinogen (IARC Group 1) and is heavily regulated under REACH, RoHS, and US EPA. Plating wastewater contains heavy metals requiring treatment by precipitation, ion exchange, or reverse osmosis. Drag-out losses from plating baths constitute the main waste source. Trivalent chromium plating is replacing hexavalent in many applications.

Соображения безопасности

Последние инновации

Trivalent chromium (Cr(III)) plating eliminates carcinogenic hexavalent chromium.
PVD (physical vapor deposition) and CVD coatings provide chrome-like appearance without wet chemistry.
Pulse and pulse-reverse plating improves deposit quality and reduces waste.
Ionic liquid electrolytes enable electroplating at room temperature for reactive metals.

Больше в Metallurgy & Metal Processing

Выплавка алюминия электролизом по методу Холла–Эру

Global Industrial Scale

Выплавка чугуна в доменной печи

Global Industrial Scale

Производство нержавеющей стали в электродуговой печи

Global Industrial Scale

Производство титана по процессу Кролла

Global Industrial Scale

Цианидное выщелачивание золота из руды

Global Industrial Scale

Электролитическое рафинирование меди для получения высокочистого металла

Global Industrial Scale

Электролитическое рафинирование цинка из сульфидной руды

Global Industrial Scale

Frequently Asked Questions

What industry uses Гальваническое покрытие для финишной обработки поверхностей (хром, никель, цинк)?
Гальваническое покрытие для финишной обработки поверхностей (хром, никель, цинк) is used in the metallurgy & metal processing sector at global industrial scale scale.
What process is involved in Гальваническое покрытие для финишной обработки поверхностей (хром, никель, цинк)?
The workpiece is cleaned (alkaline soak clean, acid pickle, electrocleaning) and racked or placed in a barrel. It is immersed in a plating bath containing dissolved metal salt, complexing agents, brighteners, and levelers. DC current deposits metal ions as a coherent metal coating. For decorative ch
What is the economic significance of Гальваническое покрытие для финишной обработки поверхностей (хром, никель, цинк)?
Гальваническое покрытие для финишной обработки поверхностей (хром, никель, цинк) has a market value of $15 billion.
What is the environmental impact of Гальваническое покрытие для финишной обработки поверхностей (хром, никель, цинк)?
Hexavalent chromium (Cr(VI)) used in traditional chrome plating is a known carcinogen (IARC Group 1) and is heavily regulated under REACH, RoHS, and US EPA. Plating wastewater contains heavy metals requiring treatment by precipitation, ion exchange, or reverse osmosis. Drag-out losses from plating b
What raw materials are used in Гальваническое покрытие для финишной обработки поверхностей (хром, никель, цинк)?
The main raw materials include: Nickel sulfate (NiSO₄) + nickel chloride (NiCl₂), Chromic acid (CrO₃), Zinc chloride or zinc sulfate.