Common Techniques for Making Signboards

1. Laser Cutting

Definition: Laser cutting is a process that utilizes numerical control technology, with lasers as the primary tool for material processing. It involves the instantaneous melting and vaporization of materials under laser irradiation to achieve the desired cutting outcome.

Advantages:

• Fast speed
• High precision (up to 0.02mm)
• Clean edges
• High-quality results
• Detailed accuracy
• Efficient material usage
• Wide application range
• Low power consumption

Disadvantages:

• Limited capability for cutting thick materials
• Not suitable for cutting very thick materials

Principles, Classification, and Characteristics of Laser Cutting:

1. Principles of Laser Cutting: Laser cutting utilizes a focused high-power density laser beam to rapidly melt, vaporize, ablate, or reach the ignition point of the material being processed. This process is often assisted by a high-speed gas jet coaxial with the beam, which blows away the molten material, thereby separating the workpiece. Laser cutting falls under the category of thermal cutting methods.
2. Classification of Laser Cutting: Laser cutting of metals can be classified into two main types: laser fusion cutting and laser oxygen cutting.a) Laser Fusion Cutting: In laser fusion cutting, the laser heats the metal material to the point of melting, and then a non-oxidizing gas (such as Ar, He, N, etc.) is blown coaxially with the beam through a nozzle, using the gas’s pressure to expel the liquid metal, forming the cut. Laser fusion cutting requires only about one-tenth of the energy needed for vaporization cutting.Laser fusion cutting is mainly used for cutting materials that are not easily oxidized or for active metals, such as stainless steel, titanium, aluminum, and their alloys.b) Laser Oxygen Cutting: Laser oxygen cutting operates similarly to oxyacetylene cutting. It employs laser as the preheating heat source and uses oxygen or other reactive gases as cutting gases. The gas blown reacts with the cutting metal, releasing a large amount of heat due to oxidation. Simultaneously, it blows out the molten oxide and melted material from the reaction zone, forming the cut. As the oxidation reaction generates significant heat during the cutting process, the energy required for laser oxygen cutting is only about half that of fusion cutting, yet the cutting speed is much faster.Laser oxygen cutting is primarily used for easily oxidizable metal materials such as carbon steel, titanium steel, and heat-treated steel.
3. Characteristics of Laser Cutting: Compared to other thermal cutting methods, laser cutting offers several distinct advantages:a) High Cutting Quality: Laser cutting achieves excellent cut quality due to its small beam size, high energy density, and fast cutting speed. The cut is narrow, with parallel sides perpendicular to the surface, and the dimensional accuracy of the cut parts can reach ±0.05mm. The cut surface is smooth and aesthetically pleasing, with roughness typically in the tens of micrometers or even less. Laser cutting can serve as the final processing step, eliminating the need for additional machining, and the parts can be used directly.b) High Efficiency: Laser cutting machines typically feature multiple CNC worktables, allowing the entire cutting process to be fully CNC-controlled. By simply changing the CNC program, different-shaped parts can be cut, enabling both two-dimensional and three-dimensional cutting.c) Fast Cutting Speed: Laser cutting offers rapid cutting speeds. For example, a 1200W laser can cut a 2mm thick low-carbon steel plate at speeds of up to 600cm/min, or a 5mm thick polypropylene resin plate at speeds of up to 1200cm/min. Since the material does not need to be clamped during laser cutting, it saves on fixture tooling and auxiliary time for loading and unloading.d) Disadvantages: Laser cutting is limited by laser power and equipment size, making it suitable only for cutting thin to medium thickness plates and pipes. Additionally, as the thickness of the workpiece increases, the cutting speed decreases noticeably. Laser cutting equipment is costly, requiring significant initial investment.

   

2. Wire Cutting
   Definition: Electric discharge wire cutting, commonly known as wire cutting, is developed based on electrical discharge piercing and shaping processes. Advantages: High precision, smooth roughness of cut surfaces. Disadvantages: High cost, slow speed.
3. Waterjet Cutting
   Definition: Also known as waterjet cutting, it’s a machine process that utilizes high-pressure water jets for cutting. It can intricately sculpt workpieces under computer control, with minimal influence from material texture. Advantages: Low cost, high speed, capable of cutting both metal and non-metal materials. Disadvantages: Lower precision.
4. Shearing
   Shearing involves using shearing machine equipment to cut sheets according to required dimensions.
5. Bending
   Bending is performed using bending machinery to fold cut sheets to the desired angle and size.
6. Heat Bending
   Heat bending involves heating plastic fittings to a specified temperature for distortion before bending them.
7. Sandblasting
   Sandblasting is the process of cleaning and roughening basic surfaces through the impact of high-speed sand streams.

8. Paint Baking

The paint baking process involves spraying several layers of paint onto a substrate, typically a high-density board, after it has been sanded to a certain level of roughness. The coated substrate is then baked at high temperatures to cure. This technique currently demands high-quality paints, ensuring excellent color rendering.

Paint baking is divided into two main categories: low-temperature paint baking, with a curing temperature of 140°-180°, and high-temperature paint baking, with a curing temperature range of 280°-400°.

High-temperature paint, also known as Polytetrafluoroethylene (PTFE), commonly referred to as Teflon, PTFE, or F4, is a high-performance special coating based on polytetrafluoroethylene resin. It exhibits the following characteristics:

1. Non-stickiness: Virtually all substances do not adhere to the PTFE coating. Even very thin films demonstrate excellent non-stick properties.
2. Heat resistance: PTFE coatings have excellent heat and low-temperature resistance. They can withstand high temperatures up to 300°C for short durations and can be used continuously between 240°C and 260°C, showing significant thermal stability. They remain operational at freezing temperatures without becoming brittle and do not melt at high temperatures.
3. Slipperiness: PTFE coatings have a low coefficient of friction. The friction coefficient varies slightly under loaded sliding conditions but typically ranges between 0.05 and 0.15.
4. Moisture resistance: The surface of PTFE coatings repels water and oil, making it resistant to solutions during production operations. If it becomes slightly dirty, it can be easily wiped clean, leading to shorter downtime and increased efficiency.
5. Wear resistance: PTFE coatings exhibit excellent wear resistance under high loads, possessing both wear resistance and non-stick properties under certain loads.
6. Corrosion resistance: PTFE is almost impervious to chemical corrosion, protecting parts from all types of chemical corrosion.

The operation principle of a paint baking room, more accurately described as a “spray paint baking room,” involves the following steps:

During painting, external air is filtered through a primary filter and sent to the top of the room by fans. It undergoes secondary filtration through top filters before entering the room. Inside the room, the air flows downward at a speed of 0.20-0.3 m/s, ensuring that paint mist particles cannot linger in the air but are instead directly expelled through bottom vents. This continuous circulation maintains air cleanliness in the room at over 98%, with the incoming air having a certain pressure to create a constant airflow around the vehicle, removing excess paint and ensuring optimal paint quality.

During baking, the air damper is adjusted to the baking position, and hot air circulates within the baking room, rapidly raising the temperature to the preset drying temperature (55°C-60°C). Fresh external air is filtered and sent to the top chamber of the baking room after undergoing heat exchange with the heat converter. It undergoes secondary filtration before being circulated internally by the air damper. While a small amount of fresh air is drawn in, most of the hot air is reheated and reused, gradually raising the temperature inside the baking room. When the temperature reaches the set level, the burner automatically shuts off; when the temperature drops below the set level, the fan and burner automatically restart to maintain a relatively constant temperature inside the baking room. Finally, when the baking time reaches the preset duration, the baking room automatically shuts down, completing the paint baking process.

Differences between Paint Baking and Spray Painting:

1. Process:
   • Paint Baking: Three coats of primer and four coats of topcoat are applied to the substrate. After each coat, the material is sent into a dust-free, constant temperature baking room.
   • Spray Painting: Putty is applied to the substrate, followed by the application of primer (which can be skipped). Finally, the paint is sprayed and allowed to air dry naturally.
2. Coating Appearance:
   • Method: Feel the edges and corners of the door panel with your hand to determine smoothness and evenness. Observe the color of the edges and corners to see if it matches the door panel.
   • Paint Baking: Smooth and even edges, consistent color. The paint film on the surface is uniform and rich in color.
   • Spray Painting: Rough edges and corners, lighter color compared to the door panel. The paint film on the surface is uneven and lacks fullness of color.
3. Texture:
   • Method: Examine the surface of the door panel under light to see if there is an orange peel effect.
   • Paint Baking: Smooth surface without texture or orange peel effect.
   • Spray Painting: Textured surface with orange peel effect, not smooth.
4. Surface:
   • Method: Run your hand over the surface of the door panel to check for dust particles and bubbles.
   • Paint Baking: Smooth and even surface without dust particles.
   • Spray Painting: Surface with particles, not smooth to the touch.
5. Durability:
   • Method: Strike the surface with a hard object.
   • Paint Baking: No abnormalities, paint film remains undamaged.
   • Spray Painting: Cracks, severe paint film peeling, white patches appear.

9. Welding

Welding, also known as fusion joining or fusion bonding, is a manufacturing process and technique used to join metals or other thermoplastic materials such as plastics through heating. Welding achieves the purpose of joining through various approaches:

1. Heating the workpieces to be joined to partially melt and form a molten pool, which solidifies upon cooling to achieve the joint. When necessary, filler material can be added to assist in joining, heating only the lower melting point of the welding material, without melting the workpieces themselves. This process relies on the capillary action of the filler material to connect the workpieces (e.g., soldering, brazing).
2. Applying pressure during welding at temperatures equivalent to or below the melting point of the workpieces to facilitate mutual penetration and joining of the two workpieces (e.g., forge welding, solid-state welding).

Depending on the specific welding process, welding can be further classified into various types such as gas welding, resistance welding, arc welding, induction welding, and laser welding, among others.

There are numerous sources of energy for welding, including gas flames, electric arcs, lasers, electron beams, friction, and ultrasonic waves. In addition to industrial settings, welding can also be performed in various environments such as outdoors, underwater, and in space. Regardless of the location, welding can pose hazards to operators, necessitating appropriate safety measures during welding operations. Potential hazards associated with welding include burns, electric shocks, eye damage, inhalation of toxic gases, and overexposure to ultraviolet radiation.

Classification of welding: Metals welding can be classified into three major categories based on the characteristics of the welding process: fusion welding, pressure welding, and brazing.

In fusion welding processes, direct contact between the molten pool and the atmosphere can lead to oxidation of metals and various alloying elements. Gases such as nitrogen and water vapor entering the molten pool can cause defects such as pores, slag inclusions, and cracks during subsequent cooling, deteriorating the quality and performance of the weld seam. To improve welding quality, various protection methods have been developed. For example, gas shielded arc welding uses gases such as argon and carbon dioxide to isolate the atmosphere, protecting the welding arc and molten pool.

Furthermore, welding is a localized rapid heating and cooling process. The constrained expansion and contraction of the welding zone due to surrounding workpiece material can lead to welding stresses and deformation in the welded component. It’s important to eliminate welding stress and correct welding deformation for critical products post-welding.

Modern welding technology can produce weld seams without internal or external defects, with mechanical properties equal to or even superior to those of the base materials. The strength of a welded joint at the junction not only depends on the quality of the weld seam but also on its geometric shape, size, loading conditions, and operating conditions.

The basic forms of joints include butt joints, lap joints, T-joints, and corner joints. The cross-sectional shape of a butt joint weld seam is determined by the thickness of the base materials and the groove form of the two edges before welding. Various groove forms are prepared at the joint edges to facilitate the insertion of welding rods or wires, especially when welding thicker steel plates.

When welding plates of different thicknesses together, the thicker plate edges are often gradually thinned to achieve uniform thickness at the joint edges, avoiding sharp changes in cross-section and serious stress concentration. Butt joints generally exhibit higher static and fatigue strength compared to other joint types.

Lap joints require simpler pre-welding preparation, easy assembly, and result in less welding deformation and residual stress, making them suitable for on-site installation and less critical structures. However, lap joints are generally not suitable for working under alternating loads, corrosive environments, high temperatures, or low temperatures.

T-joints and corner joints are typically used based on structural requirements. The characteristics of the incomplete penetration angle weld on T-joints are similar to those of lap joints. When the weld seam is perpendicular to the external force direction, it becomes a fillet weld, causing varying degrees of stress concentration on the weld surface. Fully penetrating fillet welds have similar stress conditions to butt joints.

Corner joints have lower load-bearing capacity and are generally not used alone. They are only improved when fully penetrated or when both internal and external fillet welds are present, often used at the corners of enclosed structures.

Welded products are lighter than riveted, cast, and forged components, reducing weight and saving energy for transportation vehicles. Welding provides excellent sealing and is suitable for manufacturing various types of containers. By combining welding with forging and casting, large and economically reasonable welded structures can be created, achieving high economic benefits.

The adoption of welding technology enables the efficient utilization of materials. Welded structures can use materials with different performances in different parts, fully leveraging the strengths of various materials to achieve economic efficiency and high quality. Welding has become an indispensable and increasingly important processing method in modern industry. While welding in metal processing developed relatively late compared to casting and forging processes, its growth rate has been rapid. Welded structures account for approximately 45% of steel production, and the proportion of aluminum and aluminum alloy welded structures continues to increase.

10. Polishing

Polishing refers to the process of rubbing or grinding the surface of an object to make it smooth and refined. It involves using abrasive materials such as sandpaper, pumice, or fine powders to rub against the surface of the object or coating, thereby achieving a polished finish. Polishing is a crucial step in the coating process, typically performed manually but can also be done using pneumatic or electric tools.

Polishing is integral throughout the entire coating process. It is necessary not only for raw surfaces, primers, or putty but also after applying topcoats. Its functions include removing burrs, surface rust, oil stains, and dust from the substrate surface; eliminating coarse particles and impurities from the coating surface to achieve a smooth finish; and refining the surface roughness of smooth coatings to enhance adhesion.

Polishing can be divided into dry sanding and wet sanding methods. The latter involves lubricating with water or other wetting agents to achieve a smoother surface and wash away abrasive dust.

Polishing: Polishing refers to a machining method where the surface roughness of a workpiece is reduced using mechanical, chemical, or electrochemical means to achieve a shiny, smooth surface. It involves the use of flexible polishing tools and abrasive grains or other polishing media to modify the surface of the workpiece. Polishing does not enhance the dimensional or geometric precision of the workpiece but aims to achieve a smooth surface or a mirror-like gloss, sometimes used to eliminate gloss (matte). Typically, polishing wheels are employed as polishing tools. These wheels are usually made by layering canvas, felt, or leather and clamping them between metal circular plates, with the wheel edge coated with a polishing compound consisting of finely mixed abrasives and grease.

During polishing, the high-speed rotating polishing wheel (with a circumferential speed of over 20 meters per second) is pressed against the workpiece, causing the abrasives to produce rolling and slight cutting on the workpiece surface, thereby obtaining a bright machined surface. The surface roughness generally ranges from Ra 0.63 to 0.01 micrometers. When using non-grease matte polishing compounds, they can be used to matte the bright surface to improve appearance. In mass production of bearing steel balls, the drum polishing method is often employed.

In rough polishing, a large number of steel balls, lime, and abrasives are placed in an inclined cylindrical drum. When the drum rotates, the steel balls and abrasives inside the drum randomly roll and collide to remove surface projections and reduce surface roughness, typically removing around 0.01 millimeters of excess material. In fine polishing, steel balls and scraps of fur are placed in a wooden barrel, and continuous rotation for several hours results in a dazzlingly bright surface. Polishing of precision line scales involves immersing the machined surface in a polishing solution consisting of fine-grade oxide powder and an emulsion mixture. Polishing wheels are made of finely processed wood or specially made fine felt, with a uniform and dense mesh trajectory. The surface roughness after polishing is no more than Ra 0.01 micrometers, with no surface defects visible under a microscope magnified 40 times. Additionally, there are methods such as electrolytic polishing.

Process Flow: Chemical (or electrochemical) degreasing – hot water washing – flowing water washing – rust removal (10% sulfuric acid) – flowing water washing – chemical polishing – flowing water washing – neutralization – flowing water washing – transfer to the next surface treatment process.

Working Environment: Traditional polishing processes occur in harsh environments, generating sand, iron filings, dust, etc., which severely pollute the environment.

Processing Efficiency: Manual polishing; Hock energy technology replaces grinding with turning, with a linear speed of up to 50-80 m/min and a feed rate of 0.2-0.5 mm/r, equivalent to the efficiency of semi-fine turning.

Material Consumption: Polishing requires consumption of polishing wheels, abrasives, sand belts, and other auxiliary materials.

Adaptability: Polishing can process simple surfaces such as planes, but is not suitable for processing curved surfaces. For complex surfaces such as R arcs and curved surfaces, Hock energy polishing technology can be employed.

Powder Coating: Powder coating involves using an electrostatic generator to charge plastic powder, which then adheres to the surface of a metal plate. Subsequently, it is baked at 180~220°C to melt and adhere the powder to the metal surface. Powder-coated products are commonly used for indoor enclosures, presenting either a matte or gloss finish. Powder coating powders mainly include acrylic powders and polyester powders.

Screen Printing: Screen printing, also known as silk screening, is a type of stencil printing, alongside flat printing, relief printing, and intaglio printing, collectively referred to as the four major printing methods. Stencil printing includes methods such as mimeograph, perforated flower printing, spray printing, and screen printing. The principle of stencil printing is that during printing, ink passes through holes in the printing plate (made on the base of paper film or other plates) under pressure, transferring onto the substrate (paper, ceramics, etc.), forming images or text.

Printing Methods

1. Direct Plate Making Method: The direct plate making method involves placing a substrate coated with photosensitive material, with the photosensitive film facing upwards, on a workbench. Then, a stretched mesh frame is placed flat on the substrate, and photosensitive paste is applied into the frame using a soft scraper with pressure. After thorough drying, the plastic substrate is peeled off, leaving the photosensitive film attached to the mesh, ready for exposure. Following development and drying, the silk screen printing plate is produced.

Process Flow: Mesh stretching – degreasing – drying – peeling off the substrate – exposure – development – drying – plate correction – screen sealing.

2. Indirect Plate Making Method: In the indirect plate making method, an indirect film is first exposed, then hardened with 1.2% H2O2, and developed with warm water after drying, resulting in a peelable graphic negative. During plate making, the graphic negative film is tightly adhered to the stretched silk screen, pressed to ensure adhesion, then the substrate is peeled off, and dried with air, resulting in a silk screen printing plate.

Process Flow: Mesh stretching – degreasing – drying. Indirect film – exposure – hardening – development. Combine steps 1 & 2 – adhesion – drying – plate correction – screen sealing.

3. Direct-Indirect Hybrid Plate Making Method: In this method, the photosensitive layer is first applied to the silk screen mesh frame using water, alcohol, or photosensitive adhesive. After drying with hot air, the substrate of the photosensitive film is removed, followed by exposure, and then development processing to produce the silk screen plate.
   

Advantages of Screen Printing:

1. Versatility: Screen printing is not limited by the size and shape of the substrate. Unlike traditional printing, which is usually confined to flat surfaces, screen printing can be applied to various shapes, including curved and spherical surfaces.
2. Soft Printing: Screen printing exerts minimal pressure, resulting in a soft and elastic ink layer.
3. Strong Coverage: It can achieve strong coverage even on black paper, producing vibrant and three-dimensional effects.
4. Compatible with Various Inks: Screen printing is compatible with different types of inks.
5. Strong UV Resistance: Screen printing maintains glossiness even under UV exposure, making additional processes like lamination unnecessary for some applications.
6. Flexible Printing Methods: Screen printing offers diverse printing methods.
7. Convenient Plate Making: The plate making process is straightforward, cost-effective, and easy to master.
8. Strong Adhesion: Screen printing ink adheres well to substrates.
9. Manual or Automated: Screen printing can be performed manually or with automated machinery.

UV Varnishing: UV varnishing refers to applying UV varnish through silk screen printing on specific patterns of pre-printed black graphics. After UV varnishing, these patterns appear brighter, more vibrant, and have a stronger three-dimensional effect compared to the surrounding printed areas. Due to the thick ink layer of screen printing, the cured varnish creates a raised effect similar to embossing. Screen printing UV varnishing offers superior height, leveling, and thickness compared to offset UV varnishing, making it highly favored by foreign clients.

Disadvantages:

1. Limited Multicolor Printing: Screen printing can only print one color at a time, making multicolor printing complex and prone to misalignment, increasing scrap rates and costs.
2. Small Batch Production: Due to the plate-making and film-making processes, screen printing is not economical for small batch production, resulting in higher costs.
3. Curvature Limitation: Screen printing is mainly suitable for relatively flat products. It cannot accommodate significant curvature variations.
4. Inability to Control Ink Volume: Screen printing struggles to maintain the original texture of some substrates, particularly textiles, due to the inability to control ink volume.

To address these limitations, a new technology known as flatbed printing can be employed. This digital process allows for multicolor printing in a single pass, consistent printing costs for small batch production, and can accommodate mild curvature (5-7mm). Additionally, it offers fine ink control without compromising the substrate’s texture, making it suitable for challenging products.

14. Etching: The etching process varies depending on the type of metal, but generally follows these steps: metal etching plate – degreasing – water rinsing – etching immersion – water rinsing – drying – silk screen printing – drying – immersion for 2-3 minutes – etching of patterns and text – water rinsing – ink removal – water rinsing – acid washing – water rinsing – electrolytic polishing – water rinsing – dyeing or electroplating – water rinsing – hot water rinsing – drying – soft cloth polishing – transparent varnish spraying – drying – inspection – packaging of finished products.

PET Heat Transfer Film Process

Process One: Suitable for Heterogeneous Substrates

1. Preparation: Select substrates that have been pre-coated or electrocoated.
2. Encapsulation: Wrap the substrate to be transferred with PET heat transfer film, and seal the PET film into a tubular bag using an ultrasonic sealing machine. (Note: The PET heat transfer film’s front side should be facing the transfer surface of the substrate.)
3. Vacuuming: Apply vacuum from both ends of the tubular PET heat transfer film bag until the plastic bag can fully and effectively adhere to the substrate. The negative pressure of the vacuum should be adjusted appropriately, typically between 0.3 to 0.8 Mpa, depending on factors such as the characteristics of the substrate and the negative pressure the plastic tape can withstand.
4. Baking: Send the encapsulated substrate to an oven for baking. The baking temperature and time should be adjusted appropriately based on factors such as the substrate’s characteristics, the depth of the texture to be transferred, and the specific performance of the oven. Typically, the transfer temperature ranges from 160 to 180°C, and the time ranges from 5 to 8 minutes.
5. Removal: Remove the substrate that has been transferred from the oven, and use manual or mechanical blowing (i.e., blowing up the tubular bag of PET heat transfer film) to remove the PET heat transfer film.

Process Two: Suitable for Flat Substrates

1. Preparation: Choose substrates that have been pre-coated or electrocoated.
2. Alignment: Align the front side of the wood grain heat transfer paper with the front side of the substrate to be transferred.
3. Pressing: Apply pressure and heat using a flatbed heat transfer machine. Typically, the transfer temperature ranges from 160 to 180°C, and the time ranges from 18 to 25 seconds.
   

Water Transfer Technology and Production Process

Water transfer technology involves the high-pressure hydrolysis of transfer paper/plastic film with colored patterns. As demands for product packaging and decoration increase, water transfer finds widespread applications. Its principle of indirect printing and perfect printing results solve many surface decoration challenges for various products such as ceramics and glass paper. Here’s the production process:

1. Production of Transfer Paper: Computer processed patterns are output onto film or paper, which is then printed with various colors. A cover oil is also applied to the printed paper. Alternatively, patterns can be directly printed onto transfer paper using a color laser printer.
2. Paper Soaking: Printed paper is soaked in water for approximately 30 seconds. Care should be taken not to exceed soaking time to prevent dissolution of the paper’s surface adhesive.
3. Pattern Transfer: The surface of the target object is prepared, and the soaked paper is transferred onto it. Excess water is then removed, and the surface is dried.
4. Drying: Metal, ceramic, and glass items are baked in an oven at 140°C for 20 minutes. Plastic items are baked at 70°C for 60 minutes. Items such as candles, helmets, or tempered glass do not require baking.
5. Finishing: A layer of transparent varnish or matte oil is sprayed onto the dried surface of the item. After 12 hours of drying, the pattern and decoration become permanently bonded. Skipping this step may result in poor adhesion.

Water transfer technology includes water mark transfer and water coating transfer. The latter is used for complete surface transfers while the former is used for transferring text and photo patterns. Coating transfer technology uses water-soluble films to carry images. Due to the excellent tension of the coating film, it easily adheres to the product surface, providing a solution for three-dimensional product printing similar to spray painting. It can create different appearances on curved surfaces and avoid the blank spots common in traditional surface printing. Additionally, since the product surface does not need to contact the printing film during the printing process, it avoids damage to the product surface and its integrity. Water transfer involves applying patterns onto a special chemically treated film, which is then transferred evenly onto the product surface using water pressure. The coating film automatically dissolves in water, and after washing and drying, a layer of transparent protective coating is applied, resulting in a visually distinct appearance for the product.

This revised version aims to provide a clearer and more organized presentation of the processes described. Let me know if you need further adjustments or additional information!

Electroplating Technology and Process

Electroplating is the process of depositing a thin layer of another metal or alloy onto the surface of certain metals using the principle of electrolysis. It involves the application of an electric current to create a metal film on the surface of metal or other material components, serving to prevent corrosion, improve wear resistance, conductivity, reflectivity, and enhance aesthetics.

Concept of Electroplating: During electroplating, the metal or insoluble material of the coating is used as the anode, while the workpiece to be plated acts as the cathode. The metal ions of the coating are reduced on the workpiece surface to form a uniform and firm coating. An electrolyte solution containing the metal ions of the coating is used to maintain the concentration of metal ions unchanged to eliminate interference from other cations.

Purpose of Electroplating: The primary purpose of electroplating is to deposit a metal coating on a substrate to alter its surface properties or dimensions. It enhances corrosion resistance (with corrosion-resistant metals), increases hardness, prevents wear, improves conductivity, lubricity, heat resistance, and surface appearance.

Functions of Electroplating: Electroplating deposits adherent metal coatings with different properties from the substrate material, providing decorative, protective, and functional surface layers. It can also repair worn parts and correct machining errors.

Electroplating Process: The basic steps of electroplating involve connecting the metal to be plated to the anode, connecting the object to be plated to the cathode, and immersing both electrodes in an electrolyte solution containing metal ions. When a direct current is applied, the metal of the anode oxidizes (loses electrons), and the positive ions in the solution are reduced at the cathode to form a metallic layer. The quality and appearance of the plated object depend on the current intensity; lower currents result in a more aesthetically pleasing finish.

Applications and Materials: Electroplating is commonly used for corrosion prevention, decoration, and functional purposes. Various metals and alloys such as copper, nickel, gold, palladium-nickel, and tin-lead are employed based on specific requirements. It can also be applied to specially treated plastics.

Key Elements of Electroplating:

1. Cathode: The object to be plated, such as connectors or terminals.
2. Anode: The metal to be plated, either soluble or insoluble, often noble metals like platinum or iridium.
3. Electroplating Solution: An electrolyte solution containing metal ions for plating.
4. Plating Tank: A tank capable of containing and storing the plating solution, designed for strength, corrosion resistance, and temperature resistance.
5. Rectifier: Equipment providing the direct current power source.

Basic Production Steps of Electroplating: Preparation (polishing and degreasing) → Hanging → Degreasing → Water Rinse → Electrolytic or Chemical Polishing → Acid Pickling and Activation → Pre-plating → Electroplating → Water Rinse → Post-treatment → Drying → Unhanging → Inspection → Packaging

Working Conditions: Working conditions during electroplating operations include factors such as current density, temperature, agitation, and waveform of the power source.

Electroplating technology plays a crucial role in various industries, offering solutions for corrosion resistance, aesthetics, and functional enhancements of metal and non-metal components.