There is no national standard or service provided by the thirdy party for Accelerated aging test of thermal silicone pad, this is a problem that bothered whole industry of thermal management materials. Institute of High Energy Physics Chinenese Academy  of Sciences(hereinafter referred to as IHEP) haD to explore this problem by entrust it to other enterprises. GLPOLY was honored to be the entrusted partner over “accelerated aging test”.

After two-month discussion and exploration, our test solution had been approved by IHEP, also it promises to be a standard method of aging test for thermal gap pad.

1. In order to complete this test better, GLPOLY had did extensive preparatory work.

1. Equipment

2. 2 thermal conductivity testers, 1 high temperature chamber. GLPOLY specially purchased one thermal conductivity tester and one high temperature for this test.  

3. Tooling

4. 864 sets of tooling, half of them were made in stainless steel, the rest were made in red copper.

5. 5184 metallic bolts which were used for keeping compression rate.

6. 10368 plastic bolts which were used for fastening

7. Specimen

8. 432 pcs, 2.0W/mK, 2.5mm thick, diameter 30mm

9. 432 pcs, 4.0W/mK, 1.5mm thick, diameter 30mm

10. 3456 pcs, 4.0W/mK, 0.7mm thick, diameter 30mm, auxiliary thermal gap pad used for decreasing contact thermal resistance

II. Test cycle and process

1. Test cycle: 10^th Fed---12^th Apr.

2. Process

3. Tooling assembly(upper block+specimen+lower block+plastic bolts)

4. Tested and recorded thermal conductivity and thermal resistance before aging test

5. Assembled metallic bolts and then placed specimen into high temperature chamber, set the given temperature

6. Took specimen out and removed metallic bolts, then assemble plastic bolts

7. Assembled 4.0mm thick thermal pad(upper and lower auxiliary thermal pad)

8. Tested and recorded thermal conductivity and thermal resistance

III Tested by four tiers of temperature

1. First tier: 218℃

1) 12 sets tooling, from 0 to 11

2) 18 specimens in each set,  9 pcs in 2.0W/mK and 9 pcs in 4.0W/mK

3) Test time from 1min to 8hrs, totally 12 tiers of time

2. Second tier: 245℃

1) 12 sets tooling, from 0 to 11

2) 18 specimens in each set,  9 pcs in 2.0W/mK and 9 pcs in 4.0W/mK

3) Test time from 2mins to 33hrs, totally 12 tiers of time

3. Third tier: 272℃

1) 12 sets tooling, from 0 to 11

2) 18 specimens in each set,  9 pcs in 2.0W/mK and 9 pcs in 4.0W/mK

3) Test time from 3mins to 129hrs, totally 12 tiers of time

4. Fourth tier: 298℃

1) 12 sets tooling, from 0 to 11

2) 18 specimens in each set,  9 pcs in 2.0W/mK and 9 pcs in 4.0W/mK

3) Test time from 5mins to 516h, totally 12 tiers of time

IV. Three compression rate(2.0W/mK & 4.0W/mK)

1. compression rate 10%

2. compression rate 20%

3. compression rate 30%

V. Tooling number

1. First number on left: 2 indicates 2.0W/mK, 4 indicates 4.0W/mK

2. Second one on left: 1 indicates compression rate 10%, 2 indicates compression rate 20%, 3 indicates compression rate 30%

3. Third(fourth) one of left: 0 indicates team 0, 1 indicates team 1, and so on

4. The last one: A indicates specimen A, B indicates B, and so on, for example, 429A means thermal conductivity is 4.0W/mK, compression rate is 20%, team 9 and specimen A.

VI. Record

Before and after aging test, took the specimens from chamber according to corresponding number, tested thermal conductivity and thermal resistance after 6hrs cooling in room temperature, recorded data

Summary:

After two-month accelerated aging test, we found that these two themral pads provided excellent performance and reliability, also the test method had been proven to be effective.  In recent days, IHEP informed us this test was approved, it promises to declare the accelerated aging test for thermal gap pad as a national or industial test standard.

This success of test method of accelerated aging test for thermal silicone pad inspires GLPOLY to pursue new breakthroughs.