The 11-Steps Zinc Alloy Die Casting Medal Process-Ultimate Guide from Badge Artisans Medal Manufacturer

The Most Detailed 11-Step Zinc Alloy Die-Casting Process from Badge Artisans Medal Manufacturer: Learn How Medals Are Made from Scratch

Part1:Design

Medal Design Software

Product Drafting
Common Software: PS/AI/CDR
Purpose: Design product blueprints based on customer requirements and provided logos, names, or elements to facilitate manufacturing.
Drafting Standards: Dimensions / Color Codes / Exploded views of functional components / Special process annotations
Operating Principles:
Adjust and modify existing customer designs into production-ready blueprints.
Create original designs based on the customer’s logo, name, design concepts, or elements to achieve the required product blueprint.

Badge Artisans Co., Ltd., as a manufacturer with an in-house design team, provides a one-stop free medal design service. We can deliver design mockups within 24 hours at the earliest and offer unlimited free revisions. In addition to medals, we also provide design services for lanyards, packaging, T-shirts, and related promotional products.

Part2:Molding

3D Mold Design

Based on the 2D design blueprint, software is used to create a 3D model that displays the actual shape of the product from multiple angles. This is used to confirm whether the result meets the customer’s requirements.

Mold Engraving

Purpose: To engrave the product’s shape onto the mold material based on the 3D mold drawings, which will be used for subsequent mass production.
Equipment: Mold Engraving Machine

Working Principle: Designs and layouts are created using specialized engraving software configured on a computer. The computer automatically transmits this design and layout information to the engraving machine controller. The controller then converts this information into power signals capable of driving stepper or servo motors, controlling the machine host to generate the X, Y, and Z-axis cutting paths. Simultaneously, the high-speed rotating engraving head, equipped with tools specific to the processing material, cuts the material fixed on the workstation. This process carves out various 2D or 3D relief graphics and text designed in the computer, achieving automated engraving.

Comparison Before and After Mold Engraving

Mold Assembly

Purpose: To create feeding gates, slag collection vents, and cooling water channels on the mold, facilitating the injection of alloy material into the mold until the product is formed.
Working Principle: Once mold engraving is complete, an appropriate mold base is selected based on the size of the mold insert. Feeding gates, runners, holes, and threads are then machined onto the insert according to the mold base, and ejector pins are installed. After full assembly, the mold is mounted onto the die-casting machine for trial runs.

Electrical Discharge Machining (EDM)

Purpose: To selectively create spark patterns (textures) on specific parts of the product based on customer and production requirements. Discharge levels typically range from fine to coarse (1, 2, 3, 4, 5, 6, 7…); levels 3 and 5 are the most commonly used.
Equipment: EDM Machine (Spark Machine)
Working Principle: EDM is a thermal processing method that converts electrical energy into thermal energy to rapidly melt the mold workpiece. During the process, a transitional arc discharge is generated in the gap between the electrode and the workpiece, creating a thermal effect. Simultaneously, the dielectric fluid vaporizes and explodes due to discharge pressure and heat. This causes the molten portion of the mold workpiece to be flushed into the fluid. The discharge leaves distinct marks on the workpiece, and through repetitive processing, the workpiece is shaped into the desired form.

Heat Treatment

Generally, die-casting molds do not require heat treatment, except in special circumstances. Stamping molds, however, must undergo heat treatment before they can be used for pressing.
Purpose: To improve the hardness, wear resistance, and strength of the mold, thereby extending its service life.
Equipment: Heat Treatment Furnace
Working Principle: Includes processes such as spheroidizing annealing, stabilization treatment, quenching and tempering. These heat treatment processes alter the microstructure of the steel, allowing the die-casting mold to achieve the required structural properties and performance.

Mold Making Equipments

Part3:Die-Casting

Die Casting (Casting)

Purpose: To inject molten zinc alloy liquid into the mold under machine pressure to achieve product formation.
Equipment: Die Casting Machine
Working Principle: The zinc alloy is heated into a liquid state. The molten metal is then filled from the nozzle through the runner into the die-casting mold cavity, where it solidifies and forms under pressure.

Raw Meterials

Zinc Alloy: The most commonly used zinc alloy grades for production are #3, #5, and #7. We typically use #3 zinc alloy.
Characteristics:
Excellent Casting Performance: Capable of die-casting products with complex shapes and high precision; produces castings with smooth surfaces.
Surface Treatment Versatility: Compatible with various treatments such as electroplating, electrophoresis, and spray painting.
Good Wear Resistance: Offers durable performance and high friction resistance.
Low Melting Point: Melts at 385°C, making it easy to cast and mold.

Deburring / Gate Removal

Purpose: To remove unwanted runners and burrs from the product, making subsequent polishing and production easier.
Working Principle: After the product is formed in the die-casting machine, on-site operators manually separate the product from the gate/runner. For products that are difficult to separate, tools such as pliers are used for assistance.

Part4:Polishing

Edge Polishing

Edge Grinding (Deburring)
Purpose: To smooth out excess runner burrs on the product edges using a polishing machine, ensuring the product is safe to handle without scratching or pricking hands.
Equipment: Integrated Eco-friendly Wet Grinding Machine
Working Principle: An electric motor drives a polishing wheel installed on the machine to rotate at high speed. The friction between the rotating wheel and the surface of the workpiece removes gates and burrs, achieving a smooth finish.

Surface Polishing

Purpose: To smooth out water ripples and burrs on the product surface using a polishing machine. This ensures the surface is safe to handle (not sharp or prickly) and enhances the quality of subsequent surface treatments.
Equipment: Integrated Eco-friendly Wet Grinding Machine
Working Principle: An electric motor drives a polishing wheel at high speeds. The friction between the rotating wheel and the target surface removes shallow marks and burrs, resulting in a smooth finish.

Polishing Auxiliary Tools

Part5:Riveting

Butterfly Clutch Pin Riveting

Accessory Riveting

Purpose: To rivet various accessories onto the product according to specifications, ensuring the product achieves its required functionality.
Equipment: Bench Drill Press
Working Principle: The accessory is placed onto the riveting tool head. Using the high-speed rotation of the machine, the zinc alloy riveting point is pressed and deformed to securely lock the accessory’s base in place.

Part6: Surface Treatment

Differences Between Electroplating, Electrophoresis, and Spray Painting

Plating

Dewaxing Oil

Purpose: To remove residual polishing wax left on the product surface after the polishing process.
Equipment: Ultrasonic Cleaner for Electroplating/Polishing Wax
Working Principle: The cleaning agent is heated to its boiling point. Through a transducer, the acoustic energy from a high-power ultrasonic frequency source is converted into mechanical vibration. These ultrasonic waves are radiated through the cleaning tank walls into the liquid. Under the influence of ultrasonic radiation, micro-bubbles within the liquid vibrate rapidly. This process disrupts the adhesion between the contaminants and the surface of the part, causing fatigue and detachment of the dirt layer. The vibration of these gas bubbles effectively “scrubs” the solid surface clean.

Racking

Purpose: Racks play a vital role in electroplating by providing electrical conductivity, support, and fixation for the parts. The rack is connected to the electrode, allowing current to be distributed evenly across the parts for a uniform plating finish.
Auxiliary Tool: Racks (Jigs/Fixtures)
Working Principle: Based on the size and shape of the product, specific types and specifications of racks are used to ensure the products are positioned evenly and securely.

Ultrasonic Cleaning

Purpose: To clean dust and dirt off the product surface.
Equipment: Ultrasonic Cleaning Machine
Working Principle: Through a transducer, the acoustic energy of a high-power ultrasonic frequency source is converted into mechanical vibration. These ultrasonic waves are radiated through the cleaning tank walls into the cleaning solution. Under the influence of the ultrasonic radiation, micro-bubbles in the liquid vibrate in response to the sound waves. This process destroys the adhesion between the contaminants and the surface of the parts, causing the dirt layer to suffer fatigue damage and peel off. The vibration of these gas bubbles effectively “scrubs” the solid surface.

Plating Plant Workshop

Drying

Purpose: To dry off excess moisture from the product surface.
Equipment: Tunnel Oven (Conveyor Oven)
Equipment Parameters:
Time: 40 min
Temperature: 100°C
Working Principle: The tunnel oven utilizes a hot air circulation system. It employs the principle of convection heat transfer to heat the interior of the oven, achieving the thorough drying and curing of the workpieces

Oil Spraying

Purpose: To enhance the product’s gloss and oxidation resistance. Finishes are typically categorized as Matte, Semi-matte, and Glossy.
Equipment: Electrostatic Spray Gun
Working Principle: An air hose supplies compressed air to the spray gun. A portion of this air drives a turbine, while the remainder atomizes the coating fluid. The turbine generates electrical energy, which is converted into a high-voltage current via a power pack for the gun’s electrode. A pump delivers the fluid through the hose to the gun, where it becomes electrostatically charged as it passes the electrode. The charged fluid is then attracted to the grounded workpiece, “wrapping” around it to provide an even coating across all surfaces.

Unracking

Purpose: To remove products from the racks (hanging boards) for packaging.
Working Principle: It is essential to wait until the products have completely cooled and the color/coating has fully cured before packaging. Products that have just exited the tunnel oven are too hot and the finish has not yet fully set; removing and packaging them immediately can easily lead to surface defects or quality issues.

Electrophoresis

Working Principle: Under the influence of electrical voltage, charged coating ions in the electrophoresis paint move toward the cathode (and anode). These ions react with the alkaline substances generated at the cathode surface to form insoluble matter, which then deposits uniformly onto the product surface.
Electrophoresis Colors: Common finishes include Antique Pewter, Antique Gold, Antique Bronze, Antique Copper, Matte Black, and Glossy Black.

Blackening Process (Oxidation)

Purpose: To create an oxide layer on the product surface. Once the surface is “swept” or brushed (Antique Finishing), it produces the distinctive antique contrast effect.
Working Principle: Blackening is a common chemical treatment for metal surfaces. The principle involves creating an oxide film on the metal surface to isolate it from the air, thereby achieving rust prevention. Products featuring Antique Pewter, Antique Gold, Antique Bronze, and Antique Copper finishes must all undergo this blackening treatment using a blackening solution (selenic acid or sulfide-based agents).

Drying

Purpose: To remove residual moisture from the product surface after rinsing off the blackening solution.
Equipment: Centrifugal Dryer (Spin Dryer)
Working Principle: Under high-speed rotation, centrifugal force flings the residual moisture off the product surface. Combined with heat, this process ensures the surfaces reach a fully dry state.

Racking

Purpose: To mount products onto the racking boards, establishing an electrical connection between the products and the electrodes.
Working Principle: In the electrophoresis process, coating ions are transferred to the cathode. The products must be mounted on a racking board, which acts as a conductive medium to connect the products to the cathode.
Rack Types: Racking boards are categorized into Hook Racks, Pocket/Cradle Racks, and Clip Racks.
Clip Racks: Generally used for badges and pins.
Hook Racks: Typically used for medals. The appropriate racking board is selected based on the specific physical characteristics of the product.

Electrophoretic Coloring

Purpose: Products are submerged into the corresponding electrophoresis tanks based on the required color. This process enhances the product’s aesthetic appeal, increases brightness, and extends its oxidation resistance (durability).
Color Types: Antique Gold, Antique Bronze, Antique Copper, Antique Tin, Matte Black, and Glossy Black.
Equipment: Electrophoresis Tank (E-Coating Tank)
Working Principle: Under the influence of electrical voltage, charged coating ions within the electrophoresis paint move toward the cathode (and anode). These ions react with the alkaline substances generated at the cathode surface to form insoluble matter, which then deposits uniformly onto the product surface.

Spray Painting

Purpose: To apply paint to the product surface according to the customer’s specified Pantone color codes, enhancing the product’s aesthetic appeal.
Raw Material: Epoxy Resin Paint
Equipment: Spray Gun, Water Curtain Cabinet (Water Wash Spray Booth)
Auxiliary Tools: Mesh Trays, Racking Boards

Working Principle
Water Curtain Cabinet: This system directs overspray and excess paint powder directly onto a water pool or a flowing water curtain. The odors generated during spraying and the small amount of unabsorbed paint powder are filtered through multiple layers of water curtains before being exhausted outside by a ventilation fan. This effectively purifies the working environment, protects workers’ health, and enhances the surface finish of the painted workpieces.
Spray Gun: Using compressed air, the paint is atomized into tiny droplets. These droplets are carried by the airflow and sprayed onto the surface of the object. This method is efficient and provides a high-quality, beautiful finish.

Baking

Purpose: To dry and cure the paint (hardening the finish).
Equipment: Oven (Industrial Batch Oven)
Working Principle: The oven’s hot air circulation system consists of a blower motor, a centrifugal fan (fan wheel), and electric heating elements. The motor drives the fan to push air across the heaters, where it absorbs thermal energy. This heated air is then distributed evenly through air ducts into every corner of the oven’s working chamber, ensuring a uniform baking process for all items inside.

Part7:Color Filling

Imitation Hard Enamel

Imitation Hard Enamel & Epoxy Coating (Flat Bake)
Imitation Hard Enamel : The surface is smooth and rounded with a ceramic-like texture. It can be plated in various metallic colors and filled with a wide range of color pastes.
Flat Bake with Epoxy : The surface is smooth and rounded, covered with a layer of transparent PA (Epoxy/Polyurethane) for protection and depth.

Working Principle
Imitation Enamel (Hard Enamel): This process uses specialized color pastes. After the recesses are filled with color, a cylinder polishing technique (flat polishing) is used to grind the metal ridges down to the exact same level as the color fill. This results in a perfectly flat surface with no tactile “bumps” or transitions between the metal and the color.

Soft Enamel

Purpose: To fill the recessed areas of the product with mixed enamel paint according to the Pantone color positions specified in the design draft, enhancing the product’s color and aesthetic appeal.
Effect: Features a distinct 3D tactile feel, with the metal lines visibly raised above the paint levels.
Working Principle: Soft enameling is a process performed after stamping or die-casting. The paint is injected into the metal recesses using automated machines or manual syringes.

Glitter

Purpose: To add glitter to specific areas or the entire surface of the product according to design requirements. This increases color diversity and enhances the overall aesthetic appeal.
Working Principle: Glitter is added as an enhancement to the soft enamel (baking paint) process. While the paint is being baked to a “semi-dry” state during the wiping stage (scraping off excess paint), the glitter powder is sprinkled evenly onto the surface. Depending on the product requirements, a protective layer of AP (Epoxy) glue may be applied over the top; if not required, the glitter remains as the final surface texture.

Glow-in-the-Dark

Purpose: To enable the product to emit a green fluorescence in low-light conditions, enhancing both the contrast and the aesthetic appeal of the item.
Working Principle:
Powder Form: The luminous material is in powder form. It is sprinkled evenly onto the surface of the soft enamel (baking paint) while the paint is in a “semi-dry” state during the wiping/scraping process.
Liquid Form: Luminous powder is mixed with additives to create a liquid state. After the initial layer of soft enamel has been fully baked and cured, the liquid luminous paint is then applied as a uniform coating over the base layer.

Translucent Enamel

Characteristics: It features a distinct 3D tactile feel (raised metal lines) and offers a significantly higher gloss and transparency compared to standard soft enamel. The translucent paint is filled into the recessed areas or cut-outs of the product.
Working Principle: The application of translucent paint is a process performed after stamping or die-casting. The “glass paint” is injected into the metal recesses using automated dispensing machines or manual syringes. Because of its transparency, the texture of the underlying metal (such as sandblasting or custom patterns) often remains visible through the paint.

Coloring Process

Auto Color Filling Machine

Purpose: To fill the recessed areas of the product with premixed paint according to the design blueprints. This method is faster, more efficient, and significantly reduces labor costs.
Working Principle: The system utilizes a high-definition camera for 360° panoramic imaging and automatic recognition. It can rapidly and accurately locate various complex products for positioning. The software includes a built-in inspection feature that automatically identifies and skips products that have already been colored, ensuring precise, on-demand paint application.

Manual Coloring

Purpose: For areas that are too small or intricately positioned for a machine to reach, manual coloring (hand-filling) is performed. Workers use syringes to manually “point” or dispense the paint into these precise locations.

Drying

Parameters:
Temperature: 100°C
Time: 60 min
Purpose: To bake, dry, and cure the paint, ensuring it hardens and adheres properly to the surface.
Working Principle: The oven’s hot air circulation system consists of a blower motor, a fan wheel, and electric heating elements. The blower motor drives the fan wheel to move air across the heating equipment, where it absorbs thermal energy. This heated air is then distributed evenly through air ducts into every corner of the oven’s chamber, ensuring a uniform baking process for all items inside.

Part8:Printing

UV Printing

Purpose: To print designs onto the product surface according to design requirements, enhancing aesthetic appeal. This process supports printing on 3D (contoured) products, provided the surface relief or height variance is controlled within 7mm.
Equipment: UV Flatbed Printer
Working Principle: Once the artwork is prepared via software, a print command is sent to the machine. The printer then automatically executes the design according to the instructions. While the ink is aqueous (liquid) when jetted, UV lamps mounted next to the print head carriage follow its movement, instantly irradiating the ink as it is deposited. These UV lamps operate at temperatures between 60°C and 80°C. By the time the ink application is finished, the UV light has already cured and dried the pattern completely.

Pad Printing

Purpose: To print patterns and text onto the product surface according to design specifications, meeting customer requirements and enhancing the product’s aesthetic appeal.
Equipment: Pad Printing Machine
Working Principle: The pad printing machine first uses a photographic etching process to create an intaglio (recessed) image on a steel plate. A specialized silicone print head (pad) then picks up the ink from these recesses and transfers it onto the object being printed. Additionally, custom inks can be formulated specifically to match the different materials of the products.

Screen Printing

Purpose: To print patterns and text onto the product surface according to design specifications, fulfilling customer requirements and enhancing the product’s aesthetic appeal.
Equipment: Vacuum Suction Screen Printing Machine
Working Principle: The process is based on the fundamental principle of using a screen mesh: the “image” areas of the screen have open pores that allow ink to pass through, while the “non-image” areas are blocked or sealed. During printing, ink is forced through the open mesh onto the product surface to create the desired design.

Part9: Laser Engraving

Purpose: To engrave text or patterns onto the product surface according to the design blueprints and customer requirements.
Equipment: Laser Marking Machine
Working Principle: A high-energy laser beam is directed onto the surface of the object. The light energy is instantaneously converted into thermal energy, causing the surface material to rapidly evaporate or ablate. This process allows for the precise engraving of any required text, graphics, or images onto the product’s surface.

Part 10: Assembly

Lanyard Assembly

Purpose: To press and bond the product’s webbing/ribbon onto the item using machinery, enhancing the product’s functionality and utility.
Equipment: Ultrasonic Plastic Welding Machine
Working Principle: Converted high-frequency electrical energy is transformed back into mechanical motion of the same frequency via a transducer. This mechanical motion is then transmitted to the welding head (horn) through a booster device that can adjust the amplitude. The welding head transfers the received vibrational energy to the joint of the workpiece to be welded. In this specific area, the vibrational energy is converted into thermal energy through friction, which melts and fuses the fabric/webbing together.

Part 11: Packing

Purpose: To protect the product using various packaging materials according to customer specifications or standard protection methods, ensuring safety and integrity during the transportation process.

Process Overview
Once the Quality Control (QC) and assembly stages are complete, products are packed based on specific client requirements. A variety of packaging options are available:
Plastic Bags: PP Bags, OPP Bags (Self-adhesive)
Fabric Pouches: Velvet/Flannel Bags
Paper/Display: Cardstock (Backing Cards)
Premium Options: Tin Boxes, Gift Boxes, etc.