In order to ensure the quality of the PCB board, a temperature resistance test is required. Usually, the PCB board can withstand a maximum temperature of 300 degrees for 5-10 seconds; the temperature is about 260 degrees when it is lead-free wave soldering, and it is about 240 degrees when it is leaded. So, how to do the PCB board temperature resistance test?
1. Prepare PCB template and tin furnace.
Sampling 10*10cm substrate (or laminated board, finished board) 5pcs (copper-containing substrate without blistering and delamination); substrate: more than 10cycle; laminated board:
LOWCTE15010cycle or above; HTg material: 10cycle or above; Normal material: 5cycle or above; finished board: LOWCTE1505cycle or above; HTg material: 5cycle or above; Normal material: 3cycle or above.
2. Set the temperature of the tin furnace to 288±5 degrees, and use a contact thermometer to measure and correct.
3. First soak the flux with a soft brush and smear it on the surface of the board; then use the pliers to pick up the test board and immerse it in the tin furnace, take it out after 10 seconds of timing, and visually check whether there is foaming and bursting on the board, this is 1 cycle.
4. If it is found that there is a problem of foaming and bursting, stop immersion tin immediately to analyze the initiation point f/m; if there is no problem, continue to cycle until the bursting, with 20 times as the end point;
5. Slice analysis is required at the foaming area to understand the origin of the detonation point and take pictures.
In short, it is necessary to understand the temperature resistance of PCB circuit boards of different materials in detail, so as not to exceed the maximum temperature limit, so as to avoid the scrapping of PCB circuit boards.
