T766 Datasheet

T766
Reliability Report
THERMFLOW T766
Reliability Test Report
Prepared by:
Research and Development
Chomerics Div. of Parker Hannifin Corp
84 Dragon Court, Woburn, MA 01888
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T766
Reliability Report
TABLE OF CONTENTS
Physical Properties
3
Detailed Research Reports
Summary
4
Procedure
4
Exposure Methods
Method (1.0) Room Temperature
5
Method (1.1) Heat Aging
5
Method (1.2) Temperature Cycling
5
Method (1.3) Thermal Shock
5
Method (1.4) Heat/Humidity
6
Tests and Results
Room Temperature…Table 1
7
Heat Aging…Table 2
9
Temperature Cycling…Table 3
11
Thermal Shock…Table 4
13
Heat/Humidity…Table 5
15
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SUMMARY OF PHYSICAL PROPERTIES
Property
T766
Test Method
Carrier
metal foil
Color (phase change material / foil)
light gray / silver
Visual
Phase Change Material Thickness, in (mm)
Metal Foil Carrier Thickness, in (mm)
0.0025 (0.064)
0.0010 (0.025)
ASTM D374
ASTM D374
Total Thickness, in (mm)
0.0035 (0.089)
ASTM D374
Tested at 50psi, 70ºC
Thermal Impedance, °C-in²/W
0.04
ASTM D5470
Phase Change Temperature Range, °C
51-58
ASTM D3418
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Reliability Report
Summary: Random production samples of Thermflow T766 thermal interface pads were subjected to
various environmental conditions and tested for thermal performance. No degradation in thermal
performance was found under any test condition. No evidence of delamination or drying of the joint was
seen in any case.
These tests include visual inspection and thermal resistance across the interface (θ plate-sink and ∆Tplate-sink)
Equipment:
1. AnalysisTech Phase VI Thermal Analyzer (ATA). The ATA was used to measure θplate-sink (the
2.
3.
4.
5.
difference between θjunction-sink and θjunction-plate) before and after conditioning as well as to measure the
actual temperatures of the plate and sink.
Analysis Tech Wind Tunnel. The wind tunnel was used to provide constant airflow around the
fixture assembly during testing.
Heat Source. A GE 9915 MKJW 16010A TO247 transistor was used as the heat source.
Heat Sink. Pin Fin heat sinks, 1.75 x 1.75 x 0.6 inch, attached with four-prong clips. (Newark
Electronics, Type 669052AB)
Thermflow T766. Random samples of 1.00 x 1.00 inch cut parts of T766 were taken from inventory.
Procedure:
A) Fixture assembly: A T766 pad was applied to an “as received” heat sink by removing the T766 pad
from the blue liner and applying the pad, phase change side to the heat sink, at room temperature with
finger pressure. The heat sink was then clipped to a 6061 T6, 1.8 x 1.8 x 0.8 inch, aluminum plate. A
type T thermocouple was installed in a groove in the opposite side of the aluminum plates and the
heat source transistor was attached to the center of this face of the aluminum plate with Thermattach
T412 tape such that the thermocouple was located under the center of the transistor. A second type T
thermocouple was attached to the center of the heat sink with Thermattach T412 tape. Each test
fixture was numbered.
Thermocouple
Tsink
Heat Sink
Tamb
•
T766 Phase Change
T766 Metal Foil Carrier
Embedded
Aluminum Plate
Thermattach
T412 tape
T0247
Transistor
Thermocouple Tplate
Tj
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Reliability Report
B) Thermal Testing: The test fixture was connected to the ATA and powered to 19 watts. The air speed
in the wind tunnel was set to 500 linear feet per minute. Temperatures of the junction (Tj), the
aluminum plate (Tplate), the heat sink (Tsink), and the ambient (Tamb) were recorded at equilibrium. The
heat generated during the test was used to complete the formation of the thermal joint between the
aluminum plate and the heat sink. The fixture was cooled, the thermocouples removed, and the
fixture was subjected to the appropriate environmental stress. After stress conditioning, the test
fixture was visually inspected and retested for thermal performance.
C) Visual: Each test fixture was inspected for joint separation, for material loss, and for any sign of joint
deterioration. After final data collection, the heat sink-plate assemblies were separated and the
interface further visually examined.
Exposure Methods
(1.0)
Control Study of performance after 1000 hours storage at room temperature environment (25°C).
(1.1)
Heat Aging exposure of 1,000 hours at 125°C (250°F).
Apparatus: A forced convection Blue M oven was set at 125°C. Temperature uniformity was +/5°C within oven.
Procedure: Fixtures were placed in a forced convection hot air oven maintained at 125 C +/- 5°C
for 1000 hours. Fixtures were then removed from oven and allowed to cool to room temperature
(acclimate) for two hours minimum before evaluation.
(1.2)
Temperature cycling of 1,000 cycles from 25°C to 125°C. A cycle consists of a 20 minute dwell
at 25°C, heating to 125°C at 10°C/minute, a 20 minute dwell at 125°C and cooling to 25°C
temperature at 10°C/minute.
Apparatus: Tenney environmental chamber Model 942 set to cycle from 25°C to 125°C.
Temperature uniformity was ± 2°C of set point.
Procedure: Fixtures were placed in Tenney environmental chamber for a period of 1000 cycles.
Fixtures were then removed from environmental chamber and allowed to acclimate to room
temperature for two hours minimum before testing.
(1.3)
Thermal shock exposure of 15 cycles from –50°C to 100°C.
Apparatus: Low temperature bath: The low temperature bath consisted of a one gallon capacity
insulated glass container. Excess dry ice was added to 0.75 gallon of n-propanol to cool bath to
-50°C +0/-5°C. Temperature was measured with a Type K thermocouple located approximately
one inch below the liquid surface. The bath was stirred before a temperature measurement was
taken. Temperature was consistently maintained by the addition of dry ice.
High temperature bath: The high temperature bath consisted of a one gallon capacity Pyrex
beaker filled with water. The temperature was measured with a type K thermocouple located
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Reliability Report
approximately one inch below the liquid surface. Filled beaker was placed on electrical hot plate
and maintained at a constant boil. Temperature was measured at 100°C (+0/-2°C).
Procedure: A cycle consists of placing a specimen into a 100°C boiling water bath for 5 minutes
and after removal, rapidly plunging specimen into the low temperature bath of dry
ice/isopropanol for 5 minutes. The specimen was then removed from the cold bath, and the next
cycle started immediately.
Sample fixtures: Sample specimens were placed in a solvent resistant plastic bag, the excess air
removed from the bag, and the bag hermetically sealed to ensure exposure of samples to only
temperature extremes and not liquid medium.
(1.4)
High temperature/Humidity Resistance 1000 hours, 85° C 85% RH.
Apparatus: A Tenney Versa Tenn II humidity cabinet chamber maintained at 85°C (+/-2°C) at a
relative humidity of 85% (+/- 5%)
Procedure: Fixtures were placed in a chamber and fully exposed with no attempt made to protect
metal surfaces. After constant exposure for 1000 hours samples were removed and allowed to
acclimate to room temperature for two hours minimum before testing.
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Reliability Report
Room Temperature Storage, Method 1.0
Results
Visual: There was no evidence of delamination or drying of the joint. The interface material did not
exhibit any apparent changes after exposure to this environmental test condition. The metal foil appeared
unchanged as well.
Thermal Performance: The before and after conditioning thermal resistances are given in Table 1. This
data shows that there is a slight decrease in the ∆Tplate-sink after 1000 hours storage at ambient conditions.
This change in ∆Tplate-sink is consistent with a gradual cold flow of the material at room temperature
resulting in decreased bond line thickness. This thermal performance change is not statistically
significant.
Raw Data
Table 1. Thermal Performance. Control samples in accordance with Method 1.0
Test
Fixture #
76
77
78
79
80
Average
Before Exposure
After Exposure
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
75.4
72.5
77.3
71.2
77.0
74.7
15.8
7.0
12.9
5.7
15.6
11.4
0.83
0.37
0.68
0.30
0.82
0.60
78.6
71.6
79.4
73.8
81.2
76.9
8.1
8.4
8.7
5.5
5.3
9.1
0.73
0.22
0.67
0.24
0.72
0.52
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Oneway Analysis of
θ(p-s) By 1000 hr Aging Condition
0.9
0.8
θ
0.7
0.6
(ps) 0.5
0.4
0.3
0.2
RT - initial
RT - final
1000 hr Aging Condition
Quantiles
Level
RT - initial
RT - final
Minimum 10%
0.3
0.3
0.22
0.22
25%
0.335
0.23
Means Comparisons
Dif=Mean[i]-Mean[j] RT - initial
RT - initial
0.000000
RT - final
-0.084
Median
0.68
0.67
75%
0.825
0.725
Each Pair
Student's t
0.05
90%
0.83
0.73
Maximum
0.83
0.73
RT - final
0.084000
0.000000
Alpha=0.05
Comparisons for each pair using Student's t
t=2.30600
Abs(Dif)-LSD
RT - initial
RT - final
RT - initial
-0.3738
-0.2898
RT - final
-0.2898
-0.3738
Positive values show pairs of means that are significantly different.
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T766
Reliability Report
Heat Aging @ 125°C, 1000 hours, Method 1.1
Results
Visual: There was no evidence of delamination or drying of the joint. The interface material turned a
yellow-brown color after exposure to this environmental test condition. The metal foil did not exhibit any
apparent changes.
Thermal Performance: The before and after conditioning thermal resistances are given in Table 2. This
data shows that there is a significant decrease in the ∆Tplate-sink after 1000 hours storage at 125°C. This
change in ∆Tplate-sink is consistent with the flow of the material during conditioning resulting in decreased
bond line thickness.
Raw Data
Table 2. Thermal Performance. Samples in accordance with Method 1.1
Test
Fixture #
96
97
98
99
100
Average
Before Exposure
After Exposure
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
86.6
87.6
86.4
74.3
82.3
83.4
14.6
15.2
13.5
7.8
11.2
12.5
0.77
0.80
0.71
0.41
0.59
0.66
73.5
71.1
77.3
73.3
76.3
74.3
7.2
4.8
7.6
6.3
7.8
6.7
0.38
0.25
0.40
0.33
0.41
0.35
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Reliability Report
Oneway Analysis of θ(p-s) By 1000 hr Aging Condition
0.9
0.8
θ
0.7
0.6
(ps) 0.5
0.4
0.3
0.2
125C - initial
125C - final
1000 hr Aging Condition
Quantiles
Level
125C - initial
125C - final
Minimum 10%
0.41
0.41
0.25
0.25
Means Comparisons
Dif=Mean[i]-Mean[j] 125C - initial
125C - initial
0.000000
125C - final
-0.302
25%
0.5
0.29
Median
0.71
0.38
75%
0.785
0.405
Each Pair
Student's t
0.05
90%
0.8
0.41
Maximum
0.8
0.41
125C - final
0.302000
0.000000
Alpha=0.05
Comparisons for each pair using Student's t
t=2.30600
Abs(Dif)-LSD
125C - initial
125C - final
125C - initial
-0.17776
0.124243
125C - final
0.124243
-0.17776
Positive values show pairs of means that are significantly different.
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Reliability Report
Temperature Cycling from 25°C to 125°C, 1000 cycles, Method 1.2
Results
Visual: There was no evidence of delamination or drying of the joint. The interface material did not
exhibit any visual changes after exposure to this environmental test condition. The metal foil appeared to
have a slight bronze color towards the edges of the pad on the aluminum plate side consistent with slight
oxidation of the metal alloy.
Thermal Performance: The before and after conditioning thermal resistances are given in Table 3. This
data shows that there is a slight decrease in the ∆Tplate-sink after 1000 cycles from 25°C to 125°C. This
change in ∆Tplate-sink is consistent with the flow of the material during conditioning resulting in decreased
bond line thickness. This thermal performance change is not statistically significant.
Raw Data
Table 3. Thermal Performance. Samples in accordance with Method 1.2
Test
Fixture #
81
82
83
84
85
Average
Before Exposure
After Exposure
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
69.8
73.4
75.7
71.4
68.7
71.8
8.9
6.8
13.9
6.1
5.7
8.3
0.47
0.36
0.73
0.32
0.30
0.44
72.9
75.1
75.1
73.7
76.6
74.7
4.4
4.9
7.6
3.8
8.4
5.8
0.23
0.26
0.40
0.20
0.44
0.31
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Reliability Report
Oneway Analysis of θ(p-s) By 1000 hr Aging Condition
0.8
0.7
θ
0.6
0.5
(ps) 0.4
0.3
0.2
0.1
25C-125C cycle
25C-125C cycle
- initial
- final
1000 hr Aging Condition
Quantiles
Level
25C-125C cycle - initial
25C-125C cycle - final
Minimum
0.3
0.2
10%
0.3
0.2
25%
0.31
0.215
Each Pair
Student's t
0.05
Median
0.36
0.26
75%
0.6
0.42
90%
0.73
0.44
Maximum
0.73
0.44
Means Comparisons
Dif=Mean[i]-Mean[j]
25C-125C cycle - initial 25C-125C cycle - final
25C-125C cycle - initial 0.000000
0.130000
25C-125C cycle - final -0.13
0.000000
Alpha=0.05
Comparisons for each pair using Student's t
t=2.30600
Abs(Dif)-LSD
25C-125C cycle - initial 25C-125C cycle - final
25C-125C cycle - initial -0.21338
-0.08338
25C-125C cycle - final -0.08338
-0.21338
Positive values show pairs of means that are significantly different.
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Reliability Report
Temperature Shock from -50°C to 100°C, 15 cycles, Method 1.3
Results
Visual: There was no evidence of delamination or drying of the joint. The interface material did not
exhibit any apparent changes after exposure to this environmental test condition. The metal foil remained
unchanged as well.
Thermal Performance: The before and after conditioning thermal resistances are given in Table 4. This
data shows that there is a significant decrease in the ∆Tplate-sink after 15 thermal shock cycles from -50°C to
100°C. This change in ∆Tplate-sink is consistent with the flow of the material during conditioning resulting
in decreased bond line thickness.
Raw Data
Table 4. Thermal Performance. Samples in accordance with Method 1.3
Test
Fixture #
91
92
93
94
95
Average
Before Exposure
After Exposure
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
73.7
74.5
77.3
76.4
79.2
76.2
6.7
10.5
9.9
9.1
11.8
9.6
0.35
0.55
0.52
0.48
0.62
0.50
70.7
62.7
74.1
69.7
70.7
69.6
5.9
5.5
6.1
4.9
6.5
5.8
0.31
0.29
0.32
0.26
0.34
0.30
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Reliability Report
Oneway Analysis of θ(p-s) By -50°C to 100°C 15 cycles
0.65
0.6
0.55
θ
0.5
(p-0.45
s)
0.4
0.35
0.3
0.25
-50C-100C - initial -50C-100C - final
-50°C to 100°C 15 cycles
Quantiles
Level
-50C-100C - initial
-50C-100C - final
Minimum
0.35
0.26
10%
0.35
0.26
25%
0.415
0.275
Median
0.52
0.31
Each Pair
Student's t
0.05
75%
0.585
0.33
90%
0.62
0.34
Maximum
0.62
0.34
Means Comparisons
Dif=Mean[i]-Mean[j] -50C-100C - initial -50C-100C - final
-50C-100C - initial
0.000000
0.200000
-50C-100C - final
-0.2
0.000000
Alpha=0.05
Comparisons for each pair using Student's t
t=2.30600
Abs(Dif)-LSD
-50C-100C - initial -50C-100C - final
-50C-100C - initial -0.10796
0.092036
-50C-100C - final 0.092036
-0.10796
Positive values show pairs of means that are significantly different.
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T766
Reliability Report
High Humidity Aging @ 85°C / 85% RH, 1000 hours, Method 1.4
Results
Visual: There was no evidence of delamination or drying of the joint. The exposed interface material did
not exhibit any apparent changes after exposure to this environmental test condition. The metal foil
turned a slightly yellow-gold color apparently due to oxidation from the moisture.
Thermal Performance: The before and after conditioning thermal resistances are given in Table 5. This
data shows that there is a slight decrease in the ∆Tplate-sink after 100 hours storage at 85°C and 85% RH.
This change in ∆Tplate-sink is consistent with the flow of the material during conditioning resulting in
decreased bond line thickness and is not statistically significant.
Raw Data
Table 5. Thermal Performance. Samples in accordance with Method 1.4
Test
Fixture #
86
87
88
89
90
Average
Before Exposure
After Exposure
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
Tplate, °C
∆Tplate-sink, °C
θp-s, °C/W
76.8
77.0
78.0
79.3
73.9
77.0
12.4
8.4
12.5
16.0
9.5
11.7
0.65
0.44
0.66
0.84
0.50
0.62
74.0
72.6
71.7
75.8
71.6
73.1
10.8
5.3
6.1
16.3
9.7
9.7
0.57
0.28
0.32
0.86
0.51
0.51
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Reliability Report
Oneway Analysis of θ(p-s) By 1000 hr Aging Condition
0.9
0.8
θ
0.7
0.6
(ps) 0.5
0.4
0.3
0.2
85C/85%RH - initial 85C/85%RH - final
1000 hr Aging Condition
Quantiles
Level
85C/85%RH - initial
85C/85%RH - final
Minimum
0.44
0.28
10%
0.44
0.28
25%
0.47
0.3
Median
0.65
0.51
Each Pair
Student's t
0.05
75%
0.75
0.715
90%
0.84
0.86
Maximum
0.84
0.86
Means Comparisons
Dif=Mean[i]-Mean[j] 85C/85%RH - initial 85C/85%RH - final
85C/85%RH - initial 0.000000
0.110000
85C/85%RH - final
-0.11
0.000000
Alpha=0.05
Comparisons for each pair using Student's t
t=2.30600
Abs(Dif)-LSD
85C/85%RH - initial 85C/85%RH - final
85C/85%RH - initial -0.28837
-0.17837
85C/85%RH - final -0.17837
-0.28837
Positive values show pairs of means that are significantly different.
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