Low welding current
The heat of the resistance is proportional to the square of the current, so the welding current is one of the important factors for the welding machine. heat produced. The importance of welding current not only refers to the magnitude of welding current, but also the level of current density is very important.
Melting core: Refers to the lap resistance welding, the metal part that melts and solidifies after the joint is created.
The welding process of the spot welder and the resulting thermal stress is an important factor. Adding pressure is applied to the mechanical strength of the weld, reducing the contact resistance and increasing the pressure, so that the resistance can even prevent local heating when welding, and the welding effect is consistent.
low power on time
Thermal polarization time is also an important factor, electricity is conducted by heat, and even though the total heat must be, because the welding position is different for different polarization times, the high temperature welding results are also different. low current waveform
A good combination of heat and pressure is very important for spot welding time, and the instantaneous temperature distribution must be suitable for all welding processes. According to the welding material and size, the electric current must be passed within a period of time, and the contact heat part, if the pressure is slow, it will cause local heating, and the welding effect of the spot welding machine will deteriorate. In addition, if the current is stopped sharply, the quenching of the welding sector can produce cracks and material embrittlement. So pass a small current before or after the main current, or add to the rise and fall of the current pulse.