Laser plastic welding is commonly performed using a technique known as “laser transmission welding.” In this process, two thermoplastic components are tightly joined together, either through the natural structure of the product or with the help of mechanical fixtures. A laser beam penetrates the upper component, and the energy is absorbed by the surface of the lower component, causing it to melt. Heat is then conducted upwards, causing the upper material to melt as well, ultimately forming a solid weld upon cooling.
Advantages of Plastic Laser Welding
Compared to traditional plastic joining methods, laser plastic welding offers several significant advantages:
High Precision
Laser welding provides exceptional precision and is easily controlled, making it adaptable for complex structures or tiny components.
High Efficiency
The process is fast, with high automation and easy integration into production lines.
Aesthetic Welds
The weld seams produced are strong, visually appealing, and provide excellent sealing properties without leaks or material degradation.
Efficient Heat Conduction
Laser welding heats and cools rapidly, minimizing thermal stress and vibration on the plastic parts.
Versatility
This technique is suitable for various shapes and sizes of plastic components, offering flexibility across industries.
Han’s Laser, a leader in the laser technology field, has been offering complete laser plastic welding solutions for years. The offerings cover every phase of the process, from R&D and testing to full-scale production. Han’s Laser solutions are employed in a wide range of industries, including automotive, electronics, medical devices, and home appliances, helping clients innovate and upgrade their products.
Common Laser Plastic Welding Methods
There are several key methods employed in laser plastic welding. Below are four common approaches:
1.Contour Welding
Contour welding involves using a collimated focus head to direct a laser beam along a welding path. The laser beam moves over the weld area, melting the plastic and forming a seam. Either the workpiece is fixed in place while the laser moves, or the laser remains stationary, and the component is moved along a predefined trajectory.
Expandability: The laser can focus into a small spot, allowing for adjustable weld widths by modifying the focal distance.
High Versatility: This method can weld almost any flat trajectory.
Automation-Friendly: It can easily be integrated into automated production systems, offering flexibility in the welding process.
Application of plastic laser contour welding technology
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Single-Station Contour Welding System | Sliding Table Dual-Station Contour Laser Welding System |
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Double-Layer Dual-Head Contour Laser Welding System | Robotic Arm + Contour Laser Welding System |
2.Quasi-Simultaneous Welding
Quasi-simultaneous welding uses a galvo scanning head to direct a high-speed laser beam across the weld contour. The beam moves rapidly along the welding path, sometimes scanning multiple times within seconds. Operators can program a distribution map of welding points through the user interface.
Shared Features with Contour Welding: Many characteristics overlap with contour welding, such as its flexibility in terms of welding shapes.
High Efficiency: The rapid scanning reduces thermal stress and boosts productivity.
Precision Control: Paired with collapse monitoring systems, it can precisely control collapse values during the welding process.
Application of plastic laser quasi-synchronous welding technology
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Single-Station Quasi-Synchronous Laser Welding System | SA Quasi-Synchronous Laser Welding System |
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Sliding Table Dual-Station Quasi-Synchronous Laser Welding System | Rotary Four-Station Quasi-Synchronous Laser Welding Equipment |
3.Simultaneous Welding
Simultaneous welding utilizes specialized beam-shaping optics and a multi-emitter laser to weld plastic along the entire weld contour simultaneously. The laser beam is shaped and guided along the weld seam, ensuring the entire surface melts and bonds at once. This method is ideal for parts requiring large contact areas and consistent weld quality.
Trajectory-Based Welding: The laser points are arranged along the desired welding path.
High Efficiency: Welding is completed in a single step without any relative motion between components.
Aesthetic Seams: By melting the entire contour at once, it reduces thermal stress and ensures the best-looking weld seams.
Application of plastic laser synchronous welding technology
Structure of the Sample to be Welded
Application Case of Plastic Laser Synchronous Welding Technology
4.Mask Welding
Mask welding shapes the laser beam into a linear spot, using pre-fabricated masks to block unnecessary laser exposure. Only the desired welding areas are exposed, and the laser melts the plastic precisely at these points.
Precise Control: The mask allows for exact positioning of the weld areas.
Fast Processing: Linear beam spots enable rapid scanning across the welding surface.
Application of plastic laser mask welding technology
Application of automated plastic welding technology
The Future of Laser Plastic Welding
As technological advancements continue and new plastic materials emerge, laser plastic welding will see expanded use in various manufacturing sectors. This technology holds particular promise in industries such as automotive electronics, medical devices, and aerospace. Additionally, as sustainability concerns grow and automation technologies advance, laser plastic welding will become more efficient, environmentally friendly, and intelligent, paving the way for faster, cleaner, and smarter welding solutions in the future.