Performance testing should be performed after magnesium oxide refilling, sintering, and complete cooling to room temperature. The entire process typically takes 3–5 hours. The specific time depends on the strict adherence to the sintering and cooling processes.
Key Steps and Timeline Before Performance Testing
|
Stage |
Time |
Description |
|
Sintering Holding |
1–2 hours |
Grain recrystallization completed in an inert atmosphere at 800–1000℃ |
|
Natural Cooling in Furnace |
1–2 hours |
Cooling from high temperature to <200℃ to prevent thermal stress cracking |
|
Cooling to Room Temperature After Refilling Approximately |
30–60 minutes |
Ensuring the component temperature stabilizes at around 25℃ to avoid testing errors |
Testing can be performed as early as 3 hours after the start of sintering, but it must be confirmed that the component has completely cooled and the environment is dry (RH≤30%).
Recommended Test Items and Sequence
Cold Insulation Resistance Test (500V DC)
Standard: ≥500 MΩ Use a calibrated 2500V megohmmeter to eliminate surface leakage interference. Cold Withstand Voltage Test
Standard: AC 2000V, no breakdown or flashover within 1 minute.
This test must be performed after the insulation resistance has passed the test to prevent equipment damage.
Hot and Humid Tests (to be verified later)
Hot: Insulation test within 2 seconds of power failure after 30 minutes of operation; ≥200 MΩ.
Humid: Retest after 48 hours at 40℃ and 95%RH; ≥200 MΩ. Testing without sufficient cooling may lead to data distortion or instrument misinterpretation, posing a safety hazard.
