Finishes / Powder coating

Industrial powder coating services for metal parts

Powder coating sprays a dry, electrostatically charged powder onto the part and cures it in an oven into a continuous film. It is thick, tough and available in almost any RAL color, gloss and texture. Most of its corrosion performance comes from the pretreatment under it, not from the powder alone.

Buyers specify it on enclosures, brackets, frames, panels, racks and architectural parts. Line size, hang points and masking decide which shops can run a part, so we match on those as well as on color and spec.

Send an RFQ for this finish What to put on the drawing

Steel substratebase
Zinc or iron phosphate1 to 3 µm
Polyester powder, cured60 to 100 µm

For harsher outdoor service a zinc-rich or epoxy primer powder goes under the top coat, as a two-coat system.

Section view, not to scale. Thickness values are typical, not promised.

Typical values

Typical ranges, not promised. The spec on your drawing and the process control of the shop set the real numbers.

Thickness: 50 to 100 µm per coat, two-coat systems 120 µm and up
Cure: About 160 to 200 °C metal temperature for 10 to 20 minutes, by powder
Pretreatment on steel: Iron or zinc phosphate, or a zirconium conversion
Pretreatment on aluminum: Chromate-free conversion coating or chem film
Chemistry: Polyester or super durable polyester outdoors, epoxy indoors, hybrid for general use
Color: RAL or sample, with gloss level and texture (smooth, fine texture, wrinkle)
Equipment: Conveyor line or batch booth. The oven size limits the largest part

Specs buyers call out

Put the spec and its type, class or grade on the drawing. Shops quote against it, and approvals narrow the list.

AAMA 2603 / 2604 / 2605: Organic coatings on architectural aluminumThree levels of outdoor durability, 2605 the highest
Qualicoat: Powder coating of architectural aluminum, EuropeClass 1, 2 or 3 powders, plus approved coaters
ISO 12944: Paint systems for corrosion protection of steelCorrosivity category C2 to CX and durability range
ASTM D3359 / D3363: Adhesion (cross-hatch) and pencil hardness testsCommon acceptance tests on drawings

Base materials

Name the alloy and hardness on the RFQ. Preparation changes with the base metal, and some shops only run one family.

Suits

Carbon steel sheet and structural parts
Aluminum extrusions and sheet
Hot-dip galvanized or zinc plated steel, with the right pretreatment

Needs care

Castings (gas can bubble out during cure, ask for a preheat)
Stainless steel (needs blast or a suitable primer)
Hardened or low-temper steel (cure temperature)

Not typical

Plastics and wood
Parts with rubber seals or bearings already fitted
Parts with tolerance below the coating thickness

Hardened steel over 39 HRC

Two checks for steel over 39 HRC. Acid pickling before coating can put hydrogen into the steel, so ask for blast cleaning or alkaline cleaning, or a relief bake if pickling is used (ASTM B850 is a common reference). And the cure runs near 200 °C, which can lower the hardness of low-temper steels. Give the tempering temperature on the RFQ.

When to specify it, and when to look elsewhere

A good fit for

Color, gloss and texture on steel or aluminum parts
Enclosures, panels, frames and brackets
Outdoor parts, with the right pretreatment and powder
A thick, impact resistant finish

Look elsewhere for

Threads, bores and press fits, unless masked
Parts that must conduct electricity on their surface
Tight tolerance assemblies where 80 µm matters
Small fasteners in large numbers: barrel plating or zinc flake fits better

What to put on the drawing and RFQ

Six lines that decide whether quotes compare. Missing items come back as questions and add days.

Color and glossRAL number or a sample, gloss level and texture. Without them quotes do not compare.
Powder typeIndoor, outdoor or super durable, or the AAMA or Qualicoat class.
PretreatmentPhosphate, zirconium or chem film, and any primer for harsh service.
ThicknessMinimum and maximum dry film thickness on significant surfaces.
MaskingThreads, ground points, bores and mating faces. Mark each one.
Hang pointWhere a hook or hole can go, and whether a small bare mark is accepted.

What moves the price

Shops price by load, lot and labor more than by the chemistry itself.

Parts per hook or per oven load sets most of the price
Masking can cost more than the coating
Color changes on a line add cleaning time, so small lots of special colors cost more
Two-coat systems and outdoor powders cost more per part

Plating and coating cost: what drives the price per part

Questions buyers ask

About powder coating specifically. For how matching works, see the home page.

How thick is powder coating?

Typically 50 to 100 µm for one coat. Two-coat systems with a primer are thicker. Give a minimum and maximum on the drawing if fit matters.

Is powder coating good outdoors?

Yes, with a polyester or super durable polyester powder over a proper conversion pretreatment. Epoxy powders chalk in sunlight and suit indoor parts.

Can threads be powder coated?

They are normally masked with plugs or caps. Coated threads usually need chasing afterwards, which adds cost and risks bare metal.

Can powder coat go over zinc plating or galvanizing?

Yes, as a duplex system for long outdoor life. It needs a pretreatment suited to zinc and often an outgassing step on hot-dip parts.

What limits the size of a powder coated part?

The oven and line opening of the shop. Give the largest dimension and weight on the RFQ so it goes only to shops whose line fits.

Get quotes for powder coating

Send one RFQ with the drawing, base material, spec and lot size. We match it with up to 3 shops that run this finish on a line that fits your part, and reply within 24 business hours.

Send my RFQ