Temperature-Nonthermal (TNT)-Weibull Model: Difference between revisions

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This relationship also can be expressed as the following:
This relationship also can be expressed as the following:
::<math>\,\!ln\left ( L\left ( x_{1},x_{2} \right ) \right )=\alpha _{0}+\alpha _{1}x_{1}+\alpha _{2}x_{2}</math>






{{Reference_Example_Heading4|ALTA}}
{{Reference_Example_Heading4|ALTA}}

Revision as of 17:50, 10 June 2014

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ALTA_Reference_Examples

This example validates the calculation of Temperature-nonthermal relationship for Weibull distribution.


Reference Case

Data is from Table 7.10 on page 300 in book Life Cycle Reliability Engineering by Dr. Guangbin Yang, John Wiley & Sons, 2007.


Data

Temperature and switching rate are the two stresses used in the accelerated life test for a type of 18-V compact electromagnetic relays. The cycles to failure are provided next.

Number in Group State F/S Time to State Temperature (F) Switching Rate Subset ID Number in Group State F/S Time to State Temperature (F) Switching Rate Subset ID
1 F 47154 337.15 10 1 1 F 29672 398.15 10 3
1 F 51307 337.15 10 1 1 F 38586 398.15 10 3
1 F 86149 337.15 10 1 1 F 47570 398.15 10 3
1 F 89702 337.15 10 1 1 F 56979 398.15 10 3
1 F 90044 337.15 10 1 6 S 57600 398.15 10 3
1 F 129795 337.15 10 1 1 F 7151 398.15 30 4
1 F 218384 337.15 10 1 1 F 11966 398.15 30 4
1 F 223994 337.15 10 1 1 F 16772 398.15 30 4
1 F 227383 337.15 10 1 1 F 17691 398.15 30 4
1 F 229354 337.15 10 1 1 F 18088 398.15 30 4
1 F 244685 337.15 10 1 1 F 18446 398.15 30 4
1 F 253690 337.15 10 1 1 F 19442 398.15 30 4
1 F 270150 337.15 10 1 1 F 25952 398.15 30 4
1 F 281499 337.15 10 1 1 F 29154 398.15 30 4
59 S 288000 337.15 10 1 1 F 30236 398.15 30 4
1 F 45663 337.15 30 2 1 F 33433 398.15 30 4
1 F 123237 337.15 30 2 1 F 33492 398.15 30 4
1 F 192073 337.15 30 2 1 F 39094 398.15 30 4
1 F 212696 337.15 30 2 1 F 51761 398.15 30 4
1 F 304669 337.15 30 2 1 F 53926 398.15 30 4
1 F 323332 337.15 30 2 1 F 57124 398.15 30 4
1 F 346814 337.15 30 2 1 F 61833 398.15 30 4
1 F 452855 337.15 30 2 1 F 67618 398.15 30 4
1 F 480915 337.15 30 2 1 F 70177 398.15 30 4
1 F 496672 337.15 30 2 1 F 71534 398.15 30 4
1 F 557136 337.15 30 2 1 F 79047 398.15 30 4
1 F 570003 337.15 30 2 1 F 91295 398.15 30 4
1 F 12019 398.15 10 3 1 F 92005 398.15 30 4
1 F 18590 398.15 10 3


Result

The following temperature non-thermal life stress relationship is used.

[math]\displaystyle{ \,\!L\left ( f,T \right )=Af^{B}e^{\left ( \frac{E_{a}}{kT} \right )} }[/math]

where [math]\displaystyle{ \,\!f }[/math] is the switching rate, [math]\displaystyle{ \,\!T }[/math] is temperature. [math]\displaystyle{ \,\!L\left ( f,T \right ) }[/math] is the life characteristic affected by the two stresses. This relationship is called temperature non-thermal model in ALTA.

This relationship also can be expressed as the following:

[math]\displaystyle{ \,\!ln\left ( L\left ( x_{1},x_{2} \right ) \right )=\alpha _{0}+\alpha _{1}x_{1}+\alpha _{2}x_{2} }[/math]


Results in ALTA