This article systematically introduces the concept, types, characteristics, formation principle, functions, application fields, selection considerations, and common troubleshooting measures for hammer tone powder coating. It focuses on the applications of hammer tone powder coating to help readers better understand what hammer tone powder coating is, as well as its characteristics and functions.
What Is Hammer Tone Powder Coating?
Hammer tone powder coating is a decorative powder coating that forms a three-dimensional texture resembling the hammered pattern left on metal after being struck with a hammer. It is also commonly referred to in the industry as orange peel powder coating. It not only provides workpieces with a distinctive decorative appearance but also effectively conceals surface defects such as roughness, scratches, and unevenness on the substrate.Types of Hammer Tone Powder Coating
By Texture(1) Fine Texture Type:
Features a delicate and uniform texture with an elegant decorative effect. It is mainly used for precision electronic equipment and high-end hardware products.
(2) Medium Texture Type:
Offers a clear and three-dimensional texture. It is the most widely used type and is commonly applied to security doors, household appliances, and radiators.
(3) Coarse Texture Type:
Features a bold and pronounced texture with excellent hiding power. It is mainly used for large mechanical equipment, castings, and other applications requiring strong coverage of surface imperfections.
By Color Effect
(1) Solid Color Hammer Tone:
Uses a single pigment (such as black, white, gray, or green) to create a simple and elegant three-dimensional textured finish.
(2) Two-Tone Hammer Tone:
Metallic aluminum powder or pigments of different shades are added to the base color, creating color contrast between the background and raised texture, resulting in stronger three-dimensional effects and metallic brilliance.
Characteristics of Hammer Tone Powder Coating
The main characteristics of hammer tone powder coating are as follows.(1) Excellent Decorative Appearance:
The coating film presents a uniform three-dimensional hammered texture with a distinctive metallic appearance and artistic appeal, significantly enhancing the product's overall appearance.
(2) Excellent Hiding Power:
The textured surface effectively conceals minor defects such as scratches, pinholes, welding marks, and other substrate imperfections, reducing the precision requirements for surface pretreatment.
(3) Excellent Protective Performance:
It provides outstanding adhesion, hardness, wear resistance, and corrosion resistance. Indoor-grade products meet general protection requirements, while outdoor-grade products offer excellent weather resistance for long-term substrate protection.
(4) High Application Efficiency:
The coating can be formed in a single spraying process without special processing adjustments. It also has relatively broad coating thickness tolerance, is less prone to sagging, and is easy to apply.
Formation Principle of Hammer Tone Powder Coating
The formation of hammer tone powder coating is based on differences in surface tension during the curing process, which induce the formation of a textured surface. The process consists of the following three key stages.1. Melting and Flow Stage
After electrostatic spraying, the powder enters the curing oven and melts into a liquid film when heated. During this stage, the hammer texture additive (typically long-chain alkyl-modified polysiloxane compounds) reduces the local surface tension of the coating film.
2. Texture Formation Stage
Because the hammer texture additive is unevenly distributed within the coating film, areas with lower surface tension (where the additive is present) are pulled toward areas with higher surface tension, generating vortex-like convection. Meanwhile, the metallic aluminum powder in the coating becomes directionally aligned during flow, further enhancing the visual contrast between raised and recessed areas. This uneven shrinkage and flow are "frozen" before gelation and curing, ultimately forming the characteristic three-dimensional hammered texture.
3. Curing and Solidification Stage
As the temperature continues to increase, the coating film undergoes crosslinking and curing, permanently fixing the textured surface.
Functions of Hammer Tone Powder Coating
The primary functions of hammer tone powder coating are reflected in the following aspects.
1. Decorative Enhancement
A single coating application creates a three-dimensional hammered metallic texture, giving the workpiece a distinctive artistic appearance and premium finish while significantly improving its visual appeal.
2. Defect Concealment
The textured surface effectively hides scratches, pinholes, welding marks, uneven roughness, and other substrate imperfections, reducing strict pretreatment requirements and improving production yield.
3. Surface Protection
The cured coating film provides excellent adhesion, hardness, wear resistance, and corrosion resistance. Outdoor-grade products also offer outstanding weather resistance, providing long-term protection for metal substrates against environmental corrosion.
Applications of Hammer Tone Powder Coating
Hammer tone powder coating is widely used in numerous industries, including the following.
1. Household Appliances
Security doors, radiators, washing machine panels, air conditioner housings, and similar products, where it enhances appearance while concealing minor imperfections on stamped metal components.
2. Instruments and Measuring Equipment
Enclosures for oscilloscopes, multimeters, control cabinets, and similar equipment, providing fine textured finishes that improve appearance and wear resistance.
3. Office and Civil Furniture
Filing cabinets, safes, storage racks, metal tables, chairs, and similar products, where the textured finish enhances product quality while offering excellent scratch and corrosion resistance.
4. Mechanical Equipment
Motor housings, water pumps, agricultural machinery, textile machinery, and similar equipment. Coarse texture finishes effectively conceal rough casting surfaces while providing long-term protection under outdoor or harsh operating conditions.
5. Building Materials
Outdoor railings, aluminum profiles, lighting poles, bridge accessories, and similar products. Outdoor-grade coatings provide long-lasting resistance to ultraviolet radiation and weathering while maintaining an attractive appearance.
How to Choose Hammer Tone Powder Coating
When selecting hammer tone powder coating, you may encounter uncertainty regarding the appropriate choice. Based on our industry experience, we recommend focusing on the following factors.1. Consider the Service Environment
(1) For indoor products (such as safes and office furniture), choose indoor-grade coatings (epoxy systems).
(2) For outdoor products (such as railings and architectural aluminum profiles), outdoor-grade coatings (polyester/TGIC or HAA systems) must be selected to ensure excellent weather resistance without chalking.
2. Select Texture According to Workpiece Condition
(1) Choose fine texture for smooth surfaces or products requiring a refined appearance.
(2) Choose medium texture for workpieces with minor scratches, welding marks, or general surface imperfections.
(3) Choose coarse texture for rough surfaces or castings with significant defects requiring strong hiding performance.
3. Consider Color Requirements
Choose solid colors for a clean and understated appearance. If stronger three-dimensional effects and metallic brilliance are desired, select two-tone hammer tone coatings (base color with metallic highlights).
4. Ensure Process Compatibility
Confirm that the coating is compatible with existing pretreatment processes (phosphating or silane conversion) and curing conditions (temperature and time). High-gloss, semi-gloss, or matte finishes may also be specified according to application requirements.
Common Problems and Solutions for Hammer Tone Powder Coating
The most common issues encountered during the use of hammer tone powder coating are listed below. Based on our industry experience, we provide corresponding solutions to help effectively resolve these powder coating problems.1. Texture Is Too Fine or Not Clearly Defined
Cause:
Excessive hammer texture additive.
Excessively high curing temperature or excessively rapid heating.
Excessive coating thickness.
Solution:
Reduce the hammer texture additive (typically decreasing by 0.1%–0.5%).
Lower the curing temperature or extend the low-temperature leveling period.
Control the coating thickness within 60–80 μm.
2. Texture Is Too Large or Appears as "Blooming"
Cause:
Insufficient hammer texture additive.
Aluminum powder particle size is too coarse or excessive aluminum powder content.
The pretreated surface is excessively smooth.
Solution:
Increase the hammer texture additive appropriately.
Replace with finer aluminum powder or reduce the aluminum powder ratio.
Improve substrate roughness through appropriate phosphating or sanding.
3. Local Areas Without Texture
Cause:
Incomplete degreasing during pretreatment, resulting in oil contamination.
Oil or moisture contamination in compressed air.
Poor compatibility between the hammer texture additive and the resin system.
Solution:
Strengthen the pretreatment degreasing process.
Install an additional drying filter after the oil-water separator.
Replace the additive with a more compatible one or adjust the resin formulation.
4. Unstable Gloss or Gloss Loss
Cause:
Insufficient or excessive curing.
Excessive pigments or fillers causing adsorption of the hammer texture additive.
Improper aluminum powder addition leading to oxidation.
Solution:
Strictly control oven temperature according to the curing schedule.
Adjust the pigment volume concentration (PVC) in the formulation.
Add aluminum powder through post-blending and incorporate protective additives.
5. Poor Adhesion or Brittle Coating
Cause:
Poor phosphating quality during pretreatment.
Inappropriate curing conditions (excessively high temperature causing over-crosslinking).
Solution:
Inspect the quality and thickness of the phosphate conversion coating.
Verify oven temperature to ensure complete curing within the recommended temperature range (typically 180–200°C).
If you encounter any difficult problems during the application of hammer tone powder coating, please feel free to contact us for professional technical support. We will be glad to work with you to find effective solutions and contribute to the development of the powder coating industry.
We hope this article provides you with a professional and reliable reference for the powder coating industry. We sincerely welcome your inquiries regarding powder coating product performance, industry standards, application methods, precautions, or any related questions. Please feel free to leave us a message or contact us directly. We will be pleased to provide you with more detailed product information, demonstration videos, or customized solutions to help you gain a comprehensive understanding of our products and their advantages.
