In today’s manufacturing environment, precise joining techniques are essential, especially when it comes to processing plastics. Two-step laser welding has been developed as an effective solution that overcomes the limitations of conventional single-step processes and sets new standards for processing absorbent plastics.

Challenges of single-step laser welding

Traditionally, single-step laser welding (transmission laser welding) is used on an already assembled component. This requires that one of the components be laser-transparent and the other laser-absorbing. The laser penetrates the upper component, strikes the material that absorbs the laser and melts the weld. However, this method often reaches its limits, especially when the material thickness of the components in the area to be irradiated is too high or when no laser-permeable material is available.

Two-step laser welding: flexibility and precision

The innovative two-step laser welding process offers a groundbreaking solution for overcoming these challenges and joining absorbent plastics to absorbent plastics. In the first step, the two components are separately and selectively melted on the surface before they are firmly pressed together in the second step. This eliminates the need for laser-transparent material and makes it easy to process thicker components.

Two-step laser welding is a reliable and flexible solution for the challenge of processing absorbent plastics. With a clear focus on efficiency, quality and environmental friendliness, this process is positioned as a technological pioneer in the field of laser material processing.

How does it work?

Connecting partners
LA1: Absorbent joining partner 1
LA2: Absorbent joining partner 2

Assembly structure:
Joining partners are arranged in individual nests
Both joining partners have a welding rib

Joining principle
Laser energy is applied directly to the welding ribs and melts both ribs (one or more lasers are used)
After melting, the laser(s) are switched off and the joining partners are pressed together with a defined force for a defined time

Possible applications
Applications where transparent materials cannot be used
Large parts, complex welding geometries, new materials

two-step laser welding principle

Advantages over other processes

Economic advantages

  • Simple tools
  • Very high flexibility
    • One machine with different tools for different parts
    • Time for changing part versions ~1min
  • Minimal energy consumption
  • Very low production costs

For the process

  • Clean process – no particles
  • Precise energy distribution along the welding path
    • Speed of the laser can be adjusted in certain areas to avoid overheating
  • Easy implementation of inspection systems
    • e.g. pyrometer or thermal camera for temperature detection

For production

  • Precision parts can be assembled inside the housing prior to welding
    • Parts can be mounted inside the housing before welding
    • Maintenance effort is minimal
  • Welded parts can be unloaded by hand