Process parameters of laser welding machine

There are many process parameters for laser welding machines, listed one by one below.,Power density is one of the most important parameters in laser processing. At high power densities, the surface can be heated to boiling point in microseconds, resulting in significant vaporization. Therefore, high power density aids in material removal, such as drilling and cutting. For lower power densities, the surface temperature takes several milliseconds to reach boiling point. Before the surface vaporizes, the underlying layer reaches its melting point, making it easy to form a good weld.

    The pulse waveform of the laser welding machine is an important issue in laser welding, especially in thin plate welding. When the laser beam reaches the surface of the material, the reflectivity of the laser beam changes with the temperature of the laser beam. Moreover, the reflectivity of metals varies greatly. The pulse width of the laser welding machine is an important parameter for pulsed laser welding. It is also a key parameter that determines the cost and size of the processing equipment.The effect of defocusing on the welding quality of the laser welding machine is due to the higher power density at the center of the focused laser spot, which easily evaporates into holes. On planes away from the laser focus, the power density distribution is relatively uniform.

    When the defocus amount is negative, the depth of the molten pool is larger, which is related to the formation process of the molten pool. Laser welding is widely used in manufacturing, powder metallurgy, automotive, electronics, and other fields. The circuit structure of the laser welding machine consists of the following structures. The charging circuit usesIGBTcharging circuit to improve the repetition frequency of the charging circuit. The discharge circuit is controlled by thyristors and must close the discharge.IGBTWhen the energy storage network is charging, the chargingIGBTis turned off. After a period of delay, the dischargeIGBTis connected and discharged.

    After the energy storage capacitor discharge is completed, the pre-ignition contact power generation consists of a step-up transformer, filter, current limiting resistor, current relay, and high-voltage triggering circuit. The pulse hydrogen lamp enters a normal glow discharge state during the pre-combustion process, exhibiting negative resistance characteristics. To ensure that the arc's post-glow discharge operates normally, the pre-combustion chamber circuit must have the characteristics of a large current source, thus the current limiting resistor in the pre-combustion chamber circuit is larger.

    The triggering method of the laser welding machine is internal triggering, using about50Hertz automatic triggering. When the ignition switch is closed, the high-voltage pulse transformer can generate15000-20000volts of high voltage and add it to the condenser chamber. Once pre-ignition is established, the triggering circuit will immediately disconnect automatically.

    The operating circuit of the laser welding machine controls the on-off operation of the water pump and power supply through buttons, contactors, and relays, achieving interlock protection in case of failure. The protection circuitis:cuts off the protection before ignition, and the discharge circuit forms a fault, causing the protection circuit to act and emit a fault signal. When the cooling system of the laser welding machine has insufficient circulating water flow, the flow relay is disconnected, cutting off the pre-combustion circuit and the main circuit power supply, stopping the entire machine from working.