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How to increase thermal shock resistance of the electronics components assembled on the PCB? Is there any material (or method) for increasing the thermal shock resistance of components?

Best Regards,

EDIT1 : Correct term is Thermal Shock Resistance. (Credit : comments)
EDIT2 : Procedure is seen below. T1 is -40 celcius, and T2 is 85 celcius. Is this enough to be able to find a solution ?
EDIT3 : This is an interview question comes to me for a position about the electronic design. So I have not conducted a test for observing a specific electronics component and interface fault.

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  • \$\begingroup\$ Can you quantify the thermal shock? \$\endgroup\$ – vofa Jan 26 '18 at 21:11
  • \$\begingroup\$ What temperature range? out of the Bessemer furnace and into liquid Nitrogen? \$\endgroup\$ – Solar Mike Jan 26 '18 at 21:11
  • \$\begingroup\$ You NEED to define a temperature range or end points for us. What is the 'HOT' temperature and for how long? What is the 'cold' temperature and for how long? \$\endgroup\$ – Sparky256 Jan 26 '18 at 21:22
  • \$\begingroup\$ "Thermal Shock Strength" is not a term I have heard before, and is a bit confusing. "Thermal Shock Resistance" is a term I have heard many times. \$\endgroup\$ – Sparky256 Jan 26 '18 at 21:27
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    \$\begingroup\$ Why don't you know the rate of change? Are you just "fishing" with a non-specific question? \$\endgroup\$ – Solar Mike Jan 26 '18 at 21:39
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( added after your edit 3.)
This sort of question expects the person to show awareness of root cause failure analysis as the first reply. So the solution starts with identifying the problem root cause. It usually pinpoints to a design or process weakness. Then apply appropriate design or process improvement(s). (ie. Forensic countermeasures.) For Automotive or Military market it is related to HALT/HASS reliability testing. So the question shows your experience level ranging from 0 to 10.

1) Thermal insulation compound ( generally anything plastic, silicone, conformal coating )

Unfortunately, improving Thermal shock resistance also increases thermal resistance and temperature rise in the substrate of heat generating parts.

Solutions require measurable specs. Where are yours?

Background
Shock is defined as anything > 10'C or >10'C/minute. It is intended to stress the interface of components which may expand by different coefficents (CTE) and different rates of expansion thereby testing its marginal strength with high stress.

Details of Question

The thermal test shows the test in the middle must be done in < 1 minute from T1 to T2 or the reverse which computes to a slope > 125'C/minute.

If something breaks that is a result of a design or process flaw then the solution then the flaw must be identified, fixed and verified.

This test can be performed both operating and non-operating and the failures may be permanent or temporary.

Forensic debug and electro-mechanical Engineering skills must be learned to identify the flaw and then determine how to prevent the flaw by re-design of the process or product. ( We cannot decide which or suggest how to fix it without seeing the failure.)

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  • \$\begingroup\$ Dear @Tony Stewart. EE since, I have editted questions that specs are given. \$\endgroup\$ – doner_t Jan 27 '18 at 10:22
  • \$\begingroup\$ Thankyou @doner_t Can you explain the faulty test result, what failed?and was it examined for physical root cause or which interface broke? \$\endgroup\$ – Sunnyskyguy EE75 Jan 27 '18 at 14:06
  • \$\begingroup\$ Dear @Tony Stewart. EE since '75, this is an interview question comes to me for position about the electronic design. But especially mentioned that how to increase thermal shock resistance of "SDRAM Memory like DDR3 chips". So, I have not conducted a specific test for a certain components or interface. But I have learnt that protection to the thermal shock depends on the component itself and interface. \$\endgroup\$ – doner_t Jan 27 '18 at 20:58
  • \$\begingroup\$ It usually pinpoints to a design or process weakness. Forensic countermeasures. Related to HALT/HASS reliability testing. So it shows your experience level. Not ability to learn. \$\endgroup\$ – Sunnyskyguy EE75 Jan 27 '18 at 21:06
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If the shock is caused externally- isolate. If internally- dissipate. So it's either high thermal resistance to environment or low, depends.

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  • \$\begingroup\$ Did you mean dissipate? \$\endgroup\$ – vofa Jan 26 '18 at 21:27
  • \$\begingroup\$ Yes. I am typing on the phone \$\endgroup\$ – Gregory Kornblum Jan 26 '18 at 21:28

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