The value of black e-coat is that it solves two problems at once: consistent appearance and long-term corrosion protection. These are the eight industries we serve most, with typical parts for each.
Consumer electronics asks three things of a metal part: small, precise and consistent — small parts, tight tolerances, high volume, and no perceptible color difference between units from the same batch.
| Item | Details |
|---|---|
| Typical parts | Folding-phone MIM hinges, SIM trays, camera brackets, shields, USB connector shells, key domes |
| Common substrates | MIM sintered parts, stainless steel stampings, CNC-machined aluminum |
| Process requirements | Tight thickness tolerance so assembly is unaffected; batch color difference ΔE under control; fine matte black texture; wear resistance |
| Our approach | A MIM-specific pretreatment strengthens cleaning and sealing so the porous sintered surface does not cause film defects; a spectrophotometer keeps batch color consistent; assembly tolerances and racking points are agreed with the customer at sampling |
Vehicle environments demand far more salt spray, damp heat and electrical insulation than consumer electronics, with long validation cycles and full traceability.
| Item | Details |
|---|---|
| Typical parts | Motor cores, sensor housings, LiDAR structural parts, connector shells, ECU brackets |
| Common substrates | Silicon steel, cold-rolled steel stampings, die-cast aluminum |
| Process requirements | Salt spray (1,000 h+ for stainless steel and aluminum, 48 h+ for laminated silicon-steel cores); insulation resistance ≥ 10 MΩ at 500 V DC; damp heat; thermal shock |
| Our approach | A reinforced phosphating pretreatment secures the corrosion base; high-corrosion coating formulation; insulation resistance measured and recorded on insulating parts; batch records support traceability |
Drones and robots are weight-sensitive and use a lot of aluminum and magnesium. Many of these parts are visible, so appearance consistency matters as much as mass.
| Item | Details |
|---|---|
| Typical parts | Gimbal brackets, airframe metal parts, motor mounts, robot joint structures, folding hinge mechanisms |
| Common substrates | Die-cast aluminum, extruded aluminum, magnesium alloy, MIM parts (hinges) |
| Process requirements | Thin, uniform coating that adds no meaningful weight; full coverage of complex cavities; no sagging; weather resistance |
| Our approach | E-coat throwing power is used to reach deep holes and cavities; die-cast parts get extra cleaning to remove die-release residue; gloss is matched to the customer's standard plaque in matte or gloss black |
AI servers and high-compute equipment are densely packed with metal parts that need EMI shielding and insulation while staying stable in long-term high humidity.
| Item | Details |
|---|---|
| Typical parts | Liquid-cooling server hardware, heat sinks, chassis brackets, shielding parts, rails and slides |
| Common substrates | Aluminum extrusions, cold-rolled steel, galvanized steel |
| Process requirements | Insulation performance; corrosion resistance; dimensional stability so insertion and assembly are unaffected; no coating flaking into the air path |
| Our approach | A functional e-coat option reaches insulation resistance above 10 MΩ at 500 V DC; thickness is controlled so insertion tolerances hold; adhesion grade 0 prevents flaking |
Sintered NdFeB magnets contain reactive neodymium and iron and oxidize easily. E-coating is one of the standard corrosion protection processes for them.
| Item | Details |
|---|---|
| Typical parts | Sintered NdFeB magnet blocks, bonded NdFeB rings, multi-pole rings, magnet tiles |
| Process requirements | A continuous, pore-free coating, thin enough not to affect magnetic performance or the assembly air gap |
| Our approach | Pretreatment and sealing are reinforced for the porous magnet surface; thickness is held in a sensible range (20–30 μm depending on specification); salt spray data is provided |
| Note | An e-coat cannot hide surface defects on the magnet such as voids or scratches, so incoming surface quality has to be good. |
| Item | Details |
|---|---|
| Typical parts | Smartwatch cases and band hardware, smart-glasses hinges and structures, metal trim on earbuds |
| Common substrates | Stainless steel, titanium alloy, MIM parts, aluminum |
| Process requirements | Fine surface texture, consistent gloss, resistance to sweat corrosion, wear resistance |
| Our approach | Gloss is matched to the customer's plaque with a gloss meter; the matte formulation makes fingerprints and fine scratches less visible; titanium parts get a dedicated pretreatment to secure adhesion |
| Item | Details |
|---|---|
| Typical parts | Speaker grilles, acoustic chamber metal parts, microphone mesh, cabinet grilles |
| Common substrates | Etched stainless steel, stamped mesh, aluminum |
| Process requirements | Mesh openings stay clear; color matches across every grille on one product; corrosion resistance |
| Our approach | Thickness is controlled so mesh openings do not clog or shrink; a spectrophotometer keeps batches consistent; mesh parts run on dedicated racks with a dedicated cleaning process |
| Item | Details |
|---|---|
| Typical parts | Bag hardware, furniture fittings, sanitary ware, tool fittings, zipper pulls, buckles, springs, screws |
| Common substrates | Iron, stainless steel, zinc alloy, copper |
| Process requirements | Uniform black appearance, rust protection, controlled cost |
| Our approach | High volumes run on the automatic lines to hold cost down; low-volume, high-mix work runs on the manual lines for flexible scheduling |
Sintered MIM parts have micro-porosity at the surface, so direct e-coating tends to produce pinholes and craters, and cleaning liquid trapped in the pores can bleed out during baking and spoil the film. We handle it by strengthening pretreatment cleaning (ultrasonic where needed), applying a suitable sealing treatment, and making sure parts are fully drained and blown off before baking. Film appearance is checked closely during sampling.
Three things go wrong with die-cast aluminum: gas porosity (gas escapes during baking and leaves pinholes), die-release residue (which hurts adhesion), and alloy segregation (uneven surface condition). Countermeasures: stronger degreasing, an optimized bake ramp that lets gas escape slowly, and, where necessary, a conversation with the die caster about incoming surface quality.
The coating itself is non-magnetic and does not directly change magnetic performance, but it adds dimension — roughly 20–30 μm per side — and the magnetic circuit design has to account for its effect on the assembly air gap. Bake temperature also has to stay within what the magnet grade allows; excessive heat can cause irreversible loss. We confirm the grade and temperature limits with the customer during sampling.
We can assess it. These are the industries we serve most, but e-coating applies far more widely. Three questions decide whether a part is suitable: is it conductive (e-coat needs a conductive part), can it take the bake temperature (typically 160–180 °C), and are there areas that must stay uncoated. Send us a drawing or a sample and we will give you a clear answer.