1. Deep Penetration Welding (Keyhole Welding)
Definition:
Deep penetration welding uses a high-power, focused laser beam that melts and vaporizes the material to create a narrow, deep weld. The vaporized metal forms a keyhole, allowing the laser to penetrate deeper into the material.
Key Characteristics:
High power density
Deep and narrow weld seam
Strong bonding between materials
Often creates small heat-affected zones
Applications:
Thick metal parts
High-strength structural components
Automotive and heavy machinery industries
Power battery casing, steel frames, or pressure-resistant parts
Advantages:
High welding speed
Strong weld strength
Suitable for mass production
Limitations:
May cause more thermal stress
Requires precise control of parameters
More sensitive to joint quality and fit-up
2. Heat Conduction Welding (Fusion Welding)
Definition:
Heat conduction welding uses a lower-power laser that melts the surface of the material without vaporization. The heat spreads through conduction, forming a smooth and shallow weld.
Key Characteristics:
Shallow weld depth
Smooth and attractive weld appearance
Less thermal distortion
Suitable for precise and delicate work
Applications:
Thin metal sheets (such as stainless steel or aluminum foil)
Medical devices and electronic components
Decorative parts or visible surfaces
Welding of small or heat-sensitive components
Advantages:
Excellent visual quality
Lower heat input, minimizing deformation
Easier to control and safer for delicate parts
Limitations:
Not suitable for thick materials
Lower strength compared to deep penetration welding
Conclusion
Both deep penetration welding and heat conduction welding are important techniques in the laser welding field. Choosing the right method depends on your application requirements, such as material thickness, strength demand, and aesthetic quality. Understanding their differences helps ensure optimal welding performance and product quality.
--Rayther Laser Lyra Zhang