Various Surface Finishing Options

From 1 Off To 10K+ Production

Cost Effective With Fast Turnaround

Get Your Parts With Aesthetic Looking

20+ Post Finishing Options

We provide full-spectrum, ASTM-compliant custom surface finishing and post-treatment solutions for CNC machined, injection molded, die-cast, and 3D printed parts, with standardized process control and consistent batch quality. Our finishing services fully comply with international surface treatment standards, as well as our ISO 9001:2015 and ISO 13485:2016 (SGS Authorized) quality management system requirements. We cover cosmetic appearance optimization, corrosion resistance enhancement, wear resistance improvement, and permanent traceability marking for all industrial scenarios.

We support both low-volume prototyping and high-volume production, with scalable capacity and consistent quality across batches.

This classification strictly follows ASTM International Surface Treatment Standards and aligns with our ISO 9001:2015 and ISO 13485:2016 (SGS Authorized) quality management system requirements. It is the universal classification logic adopted in the global precision manufacturing, automotive, and medical industries, divided by process principle and core function, with clear process definitions and accurate application matching, fully in line with the professional cognition of European and American industrial customers.

Core Principle: Adjust the surface morphology of parts, remove processing defects, and achieve the target roughness through physical mechanical action, without changing the chemical composition of the base material. It is the basic pretreatment process for most subsequent coating and conversion treatments.

Full removal of sharp edges, burrs, and residual machining marks from part corners, holes, and mating surfaces manually or mechanically. It eliminates assembly safety hazards, optimizes hand feel, and ensures assembly consistency of mating parts, with edge fillets precisely controlled according to drawing requirements.

Mechanical and vapor polishing removes machining marks and scratches to deliver uniform high-gloss or mirror finishes on metal and plastic parts. Enhances aesthetic appeal and corrosion resistance for medical, automotive and consumer electronics applications, with customizable material solutions.

Controlled spraying of abrasives onto the part surface via compressed air to create a uniform matte, non-reflective surface effect. It also cleans surface impurities, removes machining tool marks, and improves the adhesion of subsequent coatings, with surface roughness controllable between Ra 0.8~3.2μm as required.

For stainless steel and other corrosion-resistant alloys, which uniformly removes an ultra-thin metal layer on the surface to form an ultra-smooth, microscopically uniform surface. It improves corrosion resistance, eliminates surface contaminants, and meets the biocompatibility requirements of medical device parts.

Using vibratory tumbling equipment with abrasive media to remove micro burrs, sharp edges, and machining marks on complex-shaped parts. It achieves uniform surface smoothing and consistent roughness across batch parts, for small to medium-sized components with intricate geometries, threaded holes, and hard-to-reach features.

Mechanical grinding with high-precision abrasive belts to create uniform directional linear textures on the metal surface, presenting a high-end metallic decorative effect and hiding minor surface scratches. It is widely used in consumer electronics and industrial hardware, with customizable abrasive belt mesh and texture direction.

Core Principle: A dense, insoluble protective conversion film is formed on the surface of the base material through a controlled chemical/electrochemical reaction, which improves the corrosion resistance of the base material, enhances coating adhesion, and adjusts the surface electrical properties.

Electrochemical oxidation process for aluminum, magnesium, and titanium alloys, forming a dense porous aluminum oxide film on the surface of the base material.

Standard Anodizing: Film thickness 5~15μm, improves basic corrosion resistance, supports Pantone color dyeing, suitable for cosmetic electronic parts and decorative parts.

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Hard Coat Anodizing: Film thickness 25~100μm, forms an ultra-high hardness and wear-resistant oxide layer with hardness up to HV 300~500, suitable for heavy-duty industrial parts, high-temperature applications, and wear-resistant structural parts.

Chemical treatment for stainless steel and corrosion-resistant alloys with nitric acid/citric acid formula, which removes free iron and contaminants on the part surface, restores the natural passive film of the material, and greatly improves the inherent corrosion resistance of the base material with no dimensional change to the part. Trivalent chromium passivation is available for aluminum alloy parts, providing RoHS-compliant, high corrosion resistance protection for industrial and automotive components. It is suitable for food-grade, medical, and aerospace parts.

Chemical conversion film process for carbon steel and alloy steel, forming a uniform black Fe3O4 oxide film (film thickness 1~3μm) on the part surface. It provides basic anti-rust ability, reduces light reflection, and fully retains the precise dimensional tolerance of the part, suitable for fasteners, mechanical structural parts, and optical instrument parts.

Core Principle: A functional coating material is covered on the surface of the part by spraying, electrodeposition, etc., to provide long-term anti-corrosion, cosmetic decoration, and special functional properties (wear resistance, low friction, insulation, etc.).

Thermosetting powder is electrostatically applied to metal surfaces and heat-cured into a tough, uniform coating. Stock standard colors include black, silver, white, blue, and red, with custom colors available. Film thickness: 60~120μm. Features excellent scratch, impact and corrosion resistance and long service life.

Electrodeposition process that deposits a metal layer onto part surfaces. Enhances wear resistance, corrosion resistance, electrical conductivity, and decorative appearance. Suitable for electronic connectors, high-wear parts, optical components, and decorative hardware. Film thickness precisely controlled from 5μm to 50μm on request.

High-performance specialty coatings including low-friction non-stick PTFE, epoxy, nylon, ceramic, DLC (Diamond-Like Carbon), and TiN (Titanium Nitride) coatings. Reduces part friction coefficient, improves wear resistance, and delivers excellent chemical resistance and high-temperature stability.

Electrodeposited organic coating process forming a uniform, pinhole-free protective film on complex metal parts. Delivers excellent corrosion resistance with controllable thickness (10–30μm). Ideal for industrial and automotive components, providing consistent protection even on intricate geometries.

Core Principle: Permanent wear-resistant marks are formed on the part surface through non-contact/contact methods to realize part traceability, brand identification, and parameter marking, fully compliant with automotive PPAP and medical UDI traceability requirements.

Non-contact fiber laser process to permanently etch logos, serial numbers, barcodes, QR codes, and custom text on the part surface. The mark is clear, consistent, wear-resistant and non-falling, with no base material damage, and the position accuracy can reach ±0.01mm. Compliant with ISO 13485 specifications.

Precise transfer of custom logos, text, scales, and patterns onto the part surface through screen (silk) printing and pad printing processes. Suitable for both plastic and metal parts, with high-resolution, high-adhesion graphics for brand identification, instruction marking, and decorative applications, supporting multi-color overprinting.

Core Principle: The internal microstructure of the base material is adjusted through a controlled heating and cooling process to improve the mechanical properties of the part, ensure long-term dimensional stability, and reduce the risk of deformation during use.

Controlled heating and cooling process for metal parts, which relieves internal stress generated by machining, die casting, and 3D printing, improves material hardness, tensile strength, and fatigue resistance, and reduces the risk of part deformation. It covers stress relief annealing, solution treatment, aging treatment, quenching and tempering, etc., with process parameters customized according to the material grade and part performance requirements.

Custom-tailored surface treatment solutions — including specialized functional coatings, decorative treatments, and industry-specific processes — are available to match your part’s unique performance, cosmetic, and certification requirements. For finishes beyond our listed offerings, contact our team at selina@marigold-rapid.com to discuss your custom needs.

The part base material is the core factor determining the feasibility of the surface finishing process. Mismatch between material and process will lead to irreversible defects such as coating peeling, part deformation, and corrosion. The following are the mainstream material compatibility specifications universally used in the industry:

Standard/Hard Coat Anodizing, Powder Coating, Wet Spray Painting, Laser Marking, Trivalent Chromium Passivation

Strong Acid Passivation, Black Oxide Finishing

Anodizing

Anodizing, Citric Acid Passivation

High-Pressure Sand Blasting, Electroplating Without Conductive Pretreatment

Hard Coat Anodizing (Extremely High Defect Rate)

Electropolishing, Passivation, Electroplating, Sand/Bead Blasting, Laser Marking

Black Oxide Finishing, Powder Coating, Electroplating, Heat Treatment

Wet Spray Painting, Pad/Screen Printing, Laser Marking, Vapor Polishing

Powder Coating, Wet Spray Painting, Laser Marking

6061/7075 Aluminum Alloy

304/316 Stainless Steel

Carbon Steel/Alloy Steel

ABS/PC/PA Plastics

ADC12 Die Cast Aluminum

Almost all surface finishing processes will produce a certain thickness of the film layer, which directly affects the final dimensional tolerance of the part, which is the most common cause of tolerance out-of-spec for precision parts. We strictly follow the following industry-standard tolerance allowance specifications:

Single-sided mating surface ≥0.02mm

Single-sided mating surface ≥0.02mm

Recommended Tolerance Allowance

Standard Film Thickness Range

Surface Finishing Process

5~15μm

Standard Anodizing

Hard Coat Anodizing

25~100μm

Wet Spray Painting

20~80μm

Single-sided ≥0.05mm

Powder Coating

60~120μm

Single-sided ≥0.10mm

Electroplating

Electropolishing

5~50μm

5~20μm

Single-sided mating surface ≥0.03mm

Precision hole position ≥0.02mm

Note: For parts with strict tolerance requirements (≤±0.05mm), our engineering team will conduct a professional DFM review before production and formulate a targeted surface finishing process plan to ensure that the final dimensional tolerance fully meets the drawing requirements.

Consistency between prototype parts and mass production batches is the core concern of customers. We have established a standardized process management and control system to ensure 100% batch-to-batch consistency:

Permanent Process Parameter Archiving: For each order, we lock and archive the full process parameters, including abrasive type, coating formula, film thickness, curing temperature, laser power, etc. Repeat orders fully follow the confirmed process.

First Article Confirmation Mechanism: For repeat mass production orders, a first article will be produced for surface effect confirmation before full production, and mass production will only start after customer approval.

Standardized Quality Inspection: Professional equipment such as color difference meter, gloss meter, and film thickness meter are used for batch sampling inspection to ensure that the color, gloss, film thickness, and roughness of each batch are consistent with the sealed sample.

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1-24H Quote Response • No MOQ Required • 99.8% On-Time Fast Delivery • ISO-Certified Quality

Address: 303, 3rd floor, building A, No. 80 ChangJiang Road, Dong District, ZhongShan City, GuangDong Province, China 528403

Email: selina@marigold-rapid.com

Mobile: +86 18718750572