Principle of laser cutting machine - cutting method (2)


III melt cutting

In the laser cutting process, if an auxiliary blowing system coaxial with the laser beam is added, the removal of the melt during the cutting process is not solely by the vaporization of the material itself, but mainly by the blowing action of the high-speed auxiliary airflow, and the molten material is Continuously blowing away from the slit, such a cutting process is called melt cutting.

During the melt cutting process, the workpiece temperature no longer needs to be heated above the vaporization temperature, so the required laser power density can be greatly reduced. From the latent heat ratio of melting and vaporization of the material, the laser power required for melt cutting is only 1/10 of that of the vaporization cutting method.

IV laser dicing

This method is mainly used for: semiconductor materials; using a laser beam with a high power density to draw a shallow groove on the surface of the semiconductor material workpiece, since the groove weakens the bonding force of the semiconductor material. The method or the method of vibration causes it to break. The quality of the laser scribe is measured by the size of the surface debris and the heat affected zone.

V cold cutting

This is a new processing method that was proposed with the advent of high-power excimer lasers in the ultraviolet band in recent years. Its basic principle: the energy of ultraviolet photons is similar to that of many organic materials, and such high-energy photons are used to strike and break the bonding bonds of organic materials. Thereby achieving the purpose of cutting. This new technology has broad application prospects, and it is widely used in the electronics industry.

VI thermal stress cutting

The brittle material is heated by the laser beam. The surface is prone to generate large stresses, so that the fracture can be caused by the stress point of laser heating in a neat and fast oil. Such a cutting process is called laser thermal stress cutting. The mechanism of thermal stress cutting is that the laser beam heats a certain area of ​​the brittle material, causing it to produce a distinct temperature gradient.

When the surface temperature of the workpiece is high, expansion occurs. The lower temperature of the inner layer of the workpiece hinders the expansion, and as a result, tensile stress is generated on the surface of the workpiece. The inner layer generates radial compressive stress. When these two stresses exceed the breaking ultimate strength of the workpiece itself. Cracks appear on the workpiece. The workpiece is broken along the crack. The speed of thermal stress cutting—the magnitude of the strands is m/s. This cutting method is suitable for cutting materials such as glass and ceramics.

Summary: A laser cutting machine is a cutting technique that uses laser characteristics and lens focusing to concentrate energy to melt or vaporize the surface of the material. It can achieve the advantages of good cutting quality, fast speed, many cutting materials and high efficiency.