Professional Electroplating Service for Metal Parts
Zinc, nickel, chrome, copper, gold, and silver electroplating for corrosion protection, wear resistance, and decorative finishes. RoHS-compliant coatings from 3 to 50 μm with salt spray resistance up to 500 hours. ISO 9001 certified quality at FIRMFG.
Electroplating Service: Metal Plating for Protection and Decoration
Electroplating is an electrolytic process that deposits a thin layer of metal onto a conductive surface. By passing electric current through an electrolytic bath containing metal ions, a uniform metallic coating is bonded to the part at the atomic level. This coating provides corrosion protection, wear resistance, decorative finishes, and electrical conductivity — depending on the deposited metal.
At FIRMFG, our electroplating service covers zinc, nickel, chrome, copper, gold, and silver plating with thicknesses from 3 to 50 μm. We serve steel, copper alloys, aluminum, stainless steel, and zinc die-cast substrates. All finishes are RoHS compliant using trivalent passivation, with salt spray resistance up to 500 hours and hardness up to HV 1000 for hard chrome applications.
This guide covers the electroplating process, plating types, material compatibility, design guidelines, cost factors, and a comparison with anodizing and powder coating. Or, skip ahead and request a quote for an immediate price and lead time.
The 5-Step Electroplating Process
From raw part to finished coating, the electroplating process takes 5–7 days. Each step is critical to achieving uniform coverage, strong adhesion, and specified thickness.
Step 1: Pre-Treatment (Degreasing & Pickling)
Parts are thoroughly cleaned to remove oils, grease, and surface contaminants. Alkaline degreasing breaks down machining oils, followed by acid pickling to remove rust and scale. Proper pre-treatment is critical — any residual contamination will cause poor adhesion or plating defects.
Typical use: Alkaline soak degreasing, electrolytic degreasing, hydrochloric acid pickling
Step 2: Activation
The part surface is chemically activated to ensure uniform metal deposition. An acid dip removes the thin oxide layer that forms after pickling. For difficult substrates like stainless steel or aluminum, a specialized strike or activation step prepares the surface for adhesion.
Typical use: Acid activation, Wood's nickel strike for stainless, zincate for aluminum
Step 3: Electroplating (Electrolytic Bath)
The activated part is immersed in an electrolytic bath containing metal ions and connected as the cathode. When current flows, metal ions deposit onto the part surface. Plating thickness is controlled by current density, bath temperature, and immersion time. The result is a uniform metallic coating bonded at the atomic level.
Typical use: Zinc, nickel, chrome, copper, gold, or silver electrolytic baths
Step 4: Post-Treatment (Passivation & Drying)
The plated part undergoes post-treatment to enhance corrosion resistance and appearance. Chromate or trivalent passivation creates a protective conversion coating over zinc plating. Parts are rinsed thoroughly and dried in a warm air oven to prevent water spotting and white rust formation.
Typical use: Trivalent passivation, sealing, hot air drying
Step 5: Inspection & Quality Control
Every plated batch is inspected for coating thickness using X-ray fluorescence (XRF) or magnetic induction gauges. Visual inspection checks for coverage, brightness, and defects. Salt spray testing and adhesion testing are performed per specification. A plating certificate with thickness measurements is provided with each order.
Typical use: XRF thickness measurement, salt spray testing, adhesion tape test
Electroplating Types: Zinc, Nickel, Chrome, Copper & More
Each plating metal offers distinct properties. Choose based on your application's corrosion, wear, conductivity, and aesthetic requirements.
Zinc Plating
The most economical plating for steel corrosion protection. Zinc acts as a sacrificial coating, corroding preferentially to protect the base metal. Available with clear, yellow, black, or olive drab passivation.
Thickness: 5 – 15 μm
Hardness: HV 100 – 200
Applications: Fasteners, brackets, automotive hardware, sheet metal
Nickel Plating
Versatile plating offering excellent wear resistance and a bright, decorative silver-white finish. Nickel provides good corrosion protection and serves as an undercoat for chrome plating. Available in bright or satin finishes.
Thickness: 10 – 25 μm
Hardness: HV 400 – 600
Applications: Decorative trim, tools, optical components, automotive brightwork
Chrome Plating
Hard chrome plating delivers exceptional wear resistance and hardness up to HV 1000, ideal for functional surfaces. Decorative chrome provides a brilliant mirror finish over a nickel undercoat. Both types offer excellent corrosion and heat resistance.
Thickness: 10 – 50 μm
Hardness: HV 800 – 1000 (hard chrome)
Applications: Hydraulic rods, cylinder liners, tools, decorative trim
Copper Plating
Primarily used as an undercoat to improve adhesion and leveling for subsequent nickel-chrome plating. Copper also provides excellent electrical conductivity for electronics applications. Acid copper produces a bright, level surface.
Thickness: 5 – 15 μm
Hardness: HV 150 – 250
Applications: Undercoat for multi-layer plating, PCB edge connectors, bus bars
Gold & Silver Plating
Premium plating for high-end electrical contacts and decorative applications. Gold offers outstanding conductivity, corrosion resistance, and solderability. Silver provides the highest electrical conductivity of any metal for RF and switching contacts.
Thickness: 0.1 – 5 μm
Hardness: HV 60 – 200
Applications: Electrical contacts, connectors, jewelry, PCB gold fingers
Electroplating Specifications
Key capabilities and performance specifications of our electroplating service.
| Specification | Value |
|---|---|
| Plating Thickness | 3 – 50 μm (varies by plating type) |
| Hardness | HV 200 – 1000 (hard chrome up to HV 1000) |
| Salt Spray Resistance | 72 – 500 hours (per ASTM B117) |
| Temperature Resistance | Up to 300°C (chrome plating) |
| Surface Finish | Bright, matte, or satin |
| Quality Standard | ISO 9001:2015 Certified, RoHS Compliant |
Material Compatibility for Electroplating
Electroplating can be applied to most conductive metals. Some substrates require special pre-treatment to ensure adhesion and prevent bath contamination.
| Substrate Material | Plating Rating | Pre-Treatment Requirements |
|---|---|---|
| Carbon Steel | Excellent | Most common substrate — standard degreasing and acid pickling |
| Copper Alloys | Excellent | Minimal pre-treatment; direct plating with excellent adhesion |
| Aluminum | Good | Requires zincate pre-treatment and copper strike before plating |
| Stainless Steel | Good | Requires Wood's nickel strike or special activation step |
| Zinc Die-Cast | Moderate | Requires copper undercoat to prevent zinc contamination of bath |
Non-conductive materials such as plastics can be electroplated after a specialized chemical etching and electroless copper pre-treatment. Contact us for substrate-specific recommendations.
Design Guidelines for Electroplating
Follow these DFM rules to ensure uniform plating coverage, avoid defects, and reduce per-part cost. Electroplating has unique geometric considerations compared to other surface finishes.
| Feature | Recommended | Considerations |
|---|---|---|
| Blind Hole / Deep Hole | Aspect ratio < 3:1 | Uniformity decreases beyond 3:1 depth |
| Masking Areas | Specify on drawing | Stop-off paint or tape for non-plated areas |
| Thickness Tolerance | ±2 μm | Varies with geometry and current distribution |
| Thread Compensation | Allow for plating build-up | Pre-machine threads 0.02 mm undersized |
| Rack Marks | Specify non-critical contact area | Unavoidable electrical contact point |
| Edge Buildup | Fillets and radii preferred | Sharp edges receive thicker plating |
DFM Tips for Electroplating
- Design blind holes with an aspect ratio below 3:1. Deep holes receive less current and thinner plating at the bottom, leading to uneven coverage.
- Add fillets and radii to sharp edges. Current concentration at edges causes thicker plating buildup, which can crack or flake during service.
- Specify masking areas clearly on your drawing. Stop-off paint or tape prevents plating on threads, mating surfaces, or electrical contact zones.
- Account for plating thickness on threaded features. Pre-machine external threads 0.02 mm undersized and internal threads oversized to maintain fit after plating.
- Design drainage paths for plated parts. Trapped solution causes rinse contamination and staining. Avoid flat-bottom recesses where liquid can pool.
- Specify a non-critical area for rack contact marks. The electrical contact point required for plating will leave a small visible mark that cannot be avoided.
Electroplating vs Anodizing vs Powder Coating
Understanding how electroplating compares to other surface finishing processes helps you choose the right method for your material, function, and performance requirements.
| Criteria | Electroplating | Anodizing | Powder Coating |
|---|---|---|---|
| Material Compatibility | Ferrous & non-ferrous metals | Aluminum & titanium only | Most metals |
| Primary Function | Corrosion / wear / decorative | Corrosion / hardness | Corrosion / decorative |
| Thickness | 3 – 50 μm | 5 – 30 μm | 30 – 200 μm |
| Hardness | HV 200 – 1000 | HV 300 – 600 | HB 100 – 200 |
| Corrosion Resistance | 72 – 500 h salt spray | 300 – 1000 h salt spray | 500 – 2000 h salt spray |
| Cost | Low to medium | Medium | Low to medium |
| Environmental Impact | Moderate (chemical waste) | Low (water-based) | Low (minimal waste) |
Electroplating is the optimal choice when you need thin, metallic coatings with precise thickness control and excellent wear or corrosion resistance on conductive substrates.
Choose Electroplating When
You need thin (3–50 μm) metallic coatings for corrosion protection, wear resistance, or decorative finishes on conductive metal parts with precise thickness control.
Choose Anodizing When
You need a hard, durable oxide finish on aluminum or titanium parts. Best for corrosion resistance and color options without dimensional buildup on light alloys.
Choose Powder Coating When
You need a thick (30–200 μm) durable finish for outdoor or high-wear applications. Best for large parts where corrosion protection and color variety outweigh tight tolerances.
What Drives Electroplating Cost?
Electroplating is priced by plated surface area and plating type. Volume discounts apply as setup and handling costs are amortized across larger batches. Minimum order is $50 per batch.
Pricing Basis
By surface area
Cost = plated surface area (dm²) × plating type rate. Part geometry measured from CAD or sample.
Zinc Plating
Most economical
$0.50 – $2.00 / dm². Ideal for high-volume corrosion protection on steel fasteners and hardware.
Nickel & Chrome
Mid to high range
$1.50 – $8.00 / dm². Wear-resistant and decorative finishes requiring multi-layer plating stacks.
Gold & Silver
Premium
Precious metal pricing quoted per project. Used for electrical contacts and high-end decorative applications.
Volume Discount Pricing
| Order Quantity | Unit Price Discount | Lead Time | Notes |
|---|---|---|---|
| 10 units | Standard | 5 – 7 days | Baseline pricing per part |
| 50 units | 5% off | 7 – 10 days | Volume discount applies |
| 100 units | 10% off | 10 – 14 days | Batch processing efficiency |
| 500 units | 15% off | 2 – 3 weeks | Optimized barrel or rack plating |
| 1000 units | 20% off | 3 – 4 weeks | Maximum volume discount |
Minimum order: $50 per batch. Pricing shown is relative — actual quotes vary with part size, geometry, plating type, and masking requirements. Contact us for a detailed quote.
Electroplating Service FAQ
Answers to the most common questions about electroplating at FIRMFG.
QWhat plating thickness should I choose?
Plating thickness depends on the application and service environment. For indoor decorative parts, 5–10 μm of zinc or nickel provides adequate protection. For outdoor or corrosive environments, 15–25 μm is recommended. Hard chrome applications for wear resistance typically require 20–50 μm. Our engineers can recommend the optimal thickness based on your specific service conditions.
QIs electroplating RoHS compliant?
Yes, FIRMFG offers RoHS-compliant electroplating finishes. We use trivalent chromium passivation instead of restricted hexavalent chromium. Zinc plating with trivalent passivation, nickel plating, and tin plating are all available in RoHS-compliant formulations. Material test reports and compliance certificates are provided upon request with every order.
QHow corrosion-resistant is electroplating?
Corrosion resistance depends on the plating type, thickness, and post-treatment. Zinc plating with chromate passivation withstands 72–240 hours of salt spray testing. Nickel plating provides 200–500 hours of protection, while hard chrome can exceed 500 hours. For maximum corrosion protection, we recommend multi-layer systems such as copper-nickel-chrome stacks.
QWhat color options are available?
Zinc plating is available in clear (blue), yellow, black, and olive drab passivations. Nickel plating produces a bright silver-white or satin finish. Chrome plating is available in bright or satin, with black chrome for specialized applications. Copper plating can be left as-plated or antiqued for decorative effects.
QWhat is the minimum batch size?
Our minimum order is $50 per batch, which typically covers 10–20 small parts depending on the plating type. There is no strict part count minimum — we plate single prototypes and production batches alike. For very small parts, barrel plating processes hundreds of parts simultaneously at low cost.
QWhat is the typical lead time?
Standard electroplating lead time is 5–7 business days from receipt of parts. Rush service is available with 2–3 day turnaround for an additional fee. Complex multi-layer plating such as copper-nickel-chrome may require 7–10 days. Parts requiring special masking or fixturing may take longer. Exact lead times are provided in your quote.
Electroplating Applications
FIRMFG delivers electroplated parts to industries where corrosion protection, wear resistance, conductivity, and decorative finish quality are essential.
Automotive Parts
Brackets, fasteners, trim, engine components
Electronic Connectors
Contacts, terminals, PCB edge connectors
Plumbing Fixtures
Faucets, valves, fittings, shower hardware
Tools
Hand tools, cutting tools, jig components
Fasteners
Screws, bolts, nuts, washers, rivets
Decorative Hardware
Door hardware, jewelry, cosmetic parts
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Explore our other surface finishing capabilities and process-specific guides.
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Learn MoreAnodizing Service
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Learn MoreStart Your Electroplating Project
Send us your parts or CAD files and get a free electroplating quote within 24 hours. Our engineers provide plating type recommendations, thickness guidance, and DFM feedback at no cost. ISO 9001 certified quality, RoHS-compliant finishes, and 5-day turnaround.