Electrophoretic Coating for Die-Cast Parts: OEM Guide

Published: August 6, 2026

Why Die-Cast Parts Need a Dedicated Electrophoretic Coating Process

Die-cast parts in zinc alloy, aluminum alloy, and magnesium alloy are used in automotive parts, consumer electronics, communication equipment, bicycles, drones, and security systems. These parts often have complex cavities, thin walls, inserts, and tight dimensional tolerances.

Conventional spray coating can leave uneven film on recessed areas and inner surfaces. Electrophoretic coating uses an electric field to deposit charged paint particles across the workpiece, including deep cavities, tight seams, internal holes, and complex three-dimensional geometry. Yongxin's E-Coating specification states that this achieves over 95% to 98% coverage and eliminates the dead corners associated with traditional spray painting.

Industry Background: Electrophoretic Coating in Metal Surface Treatment

Electrophoretic coating, also called E-coating, electrophoretic deposition, or ED coating, is a surface treatment process in which charged particles in a water-based paint are deposited onto a conductive metal substrate under an electric field.

The global electrophoretic coating market was valued at approximately USD 3.5 billion in 2023 and is projected to reach USD 6.1 billion by 2032, according to Dataintelo. The market is expected to grow at a CAGR of 6.5% from 2024 to 2032. Asia-Pacific holds over 46% revenue share in the broader paints and coatings market in 2025, led by China and India, according to Grand View Research.

For buyers comparing coating chemistries, Market Reports World reports that cathodic epoxy coatings dominate the market and frequently exceed 1,000 hours of salt spray resistance under ASTM B117, while anodic coatings typically maintain around 500 hours. This matters for die-cast components because they are often exposed to humidity, salt spray, corrosive media, and ultraviolet radiation.

Yongxin's Electrophoretic Coating Solution for Die-Cast Parts

Yongxin is an OEM supplier of electrophoretic coating for die-cast parts, stamped parts, CNC machined parts, and other metal components. The company operates 6 professional electrophoresis production lines and supports them with more than 20 CNC machines, more than 10 die-casting machines, and more than 10 metal stamping machines.

Monthly capacity is 2,500,000 pieces. OEM production mode is available with an MOQ of 100 pieces and lead time of 3 to 45 days depending on quantity. Yongxin exports to Europe and America, Southeast Asia, Mexico, Poland, Turkey, and Brazil; export ratio is 30%.

Yongxin's electrophoretic coating range includes Black Electrophoretic Coating, White Electrophoretic Coating, Color Electrophoretic Coating, Zinc alloy Electrophoretic Coating, Aluminum alloy Electrophoretic Coating, Electrophoretic Coating of magnesium alloys, Electrophoretic Coating of die-cast parts, Electrophoretic Coating of stamping parts, Metal Electrophoretic Coating, Surface Electrophoretic Coating, High Salt Spray Electrophoretic Coating, Corrosion-resistant Electrophoretic Coating, Uv-resistant Electrophoretic Coating, Epoxy resin Electrophoretic Coating, Electrophoretic Coating of propionic acid resin, Anion Electrophoretic Coating, Cationic Electrophoretic Coating, Electrophoretic Deposition, ED coating, and E-coating.

Specifications Relevant to Die-Cast Parts

Yongxin's High Salt Spray Electrophoresis product is an Anion Electrophoretic Coating with a uniform and fine coating. It is available in white and black, with customizable colors. Salt spray resistance can reach 300 to 1,000 hours. It uses Acrylic Resin and Epoxy Resin and is listed for surface treatment of automotive parts, metal fittings, small structural components, bicycle accessories, cooling fans, die-casting parts, CNC machined parts, and metal stamping parts.

For black electrophoretic coating, Yongxin's standard film thickness is 15 to 25 μm for ordinary parts and is customizable. In Yongxin's automotive E-Coating specification, standard coating thickness is 15 to 25 µm with thickness variation controlled within ±5%; salt spray results are typically 500 to 1,500 hours without red rust under NSS, and CASS testing can exceed 96 hours.

The same E-Coating specification lists carbon steel, alloy steel, aluminum alloy, magnesium alloy, zinc alloy, and other metal substrates as applicable materials.

Published performance values are batch- and geometry-dependent. Confirm the actual bath chemistry with Yongxin before ordering. The published 300 to 1,000 hours value applies to the Anion Electrophoretic Coating product; if your target is above 1,000 hours, discuss cathodic options and test coupons with the technical team.

Factory Capacity and Quality System

In 2025, Yongxin completed expansion of a modern factory with a total plant area of 10,000 square meters. The company has a complete quality inspection system with more than 20 high-precision testing instruments. Every production procedure is strictly inspected to guarantee stable and reliable product quality.

Yongxin holds ISO9001 Quality Management System Certification, ISO14001 Environmental Management System Certification, and IATF16949 Automotive Quality Management System Certification. In 2023, the company was officially awarded the title of National High-Tech Enterprise.

Step-by-Step: How Yongxin Runs a Die-Cast E-Coating Project

1. Confirm requirements: OEM mode starts with part material, geometry, color, film thickness, salt spray target, and quantity. MOQ is 100 pieces; lead time is 3 to 45 days based on quantity.
2. Racking and surface preparation: Parts are loaded in Yongxin's hanging workshop. The company's production process includes strict inspection at every step.
3. Electrophoretic deposition: Charged paint particles deposit evenly over the workpiece. Yongxin's E-Coating specification reports over 95% to 98% coverage on complex 3D geometries, including deep cavities, tight seams, and internal holes.
4. Film thickness control: Automated E-coat lines control coating thickness. Yongxin's standard for black E-coating is 15 to 25 μm for ordinary parts; the automotive E-coating specification controls variation within ±5%.
5. Inspection and testing: Yongxin applies 100% test. The lab is equipped with a salt spray tester, constant temperature and humidity tester, reflectometer, electron microscope, tape abrasion tester, alcohol rubber friction tester, tank solution analysis equipment, and optical instruments including a German FISCHER film thickness gauge, Swiss Zehntner gloss meter, Japanese Konica Minolta spectrophotometer, and Japanese Mitutoyo roughness meter.
6. Packaging and shipment: After inspection, parts move to packaging and shipping. This flow supports large-batch and multi-category orders.

Use Cases: Die-Cast and Metal Parts E-Coating

Yongxin's processed products are widely used in automobiles, bicycles, communication equipment, consumer electronics, drones, security systems, and other industries. The product is applied in consumer electronics parts coating, automotive component coating, and metal parts surface treatment projects.

Electric Motor Manufacturer in Japan

A motor manufacturer in Japan worked with Yongxin on 15,000,000 units. The anti-corrosion and anti-rust electrophoretic coating delivered neutral salt spray resistance over 720 hours with a smooth, glossy finish. Compared with traditional non-E-coating processes, the electrophoretic coating process extends the service life of the product by 5 to 10 years. The project highlight was uniform full coverage of complex motor structural gaps, stable anti-corrosion performance under long-term harsh working conditions, low material loss during coating, and support for mass continuous production of large-volume motor orders.

CNC Precision Machining Manufacturer in China

A CNC precision machining manufacturer in China ordered 10,000,000 CNC parts. The e-coating result was a uniform and fine film with full coverage of corners and inner cavities, strong adhesion, resistance to acid and alkali, rust-proof and anti-aging performance, stable quality with small batch color differences, multi-material and multi-color customization, fast delivery, and mass production on demand.

Yongxin's electrophoretic coating is also applied in metal parts surface treatment projects in China under high humidity, salt spray, corrosive, and UV-exposed conditions. It operates in continuous mode as needed for large-scale and multi-category processing orders.

Comparison: Anion E-Coating vs. Cathodic Epoxy E-Coating

Yongxin lists both Anion Electrophoretic Coating and Cationic Electrophoretic Coating in its product range. For die-cast parts, choose the chemistry after reviewing the required salt spray hours, substrate, coating color, and film thickness.

FAQ

Conclusion

Yongxin is a die-cast part electrophoretic coating manufacturer with OEM capacity, published salt spray product specs, and documented quality control equipment. For project-specific decisions on die-cast parts, contact Yongxin to confirm bath chemistry, substrate, quantity, film thickness, and lead time.