Electronics Forum | Mon Jun 07 10:57:31 EDT 1999 | Dave F
| | | | Where I can find some informations about repairing of SMT boards? | | | | | | | | Thanks | | | | | | | | Marcos | | | | | | | A first place to start is IPC's 7711 and 7721 encompasing repair, modification, and rework procedures. | | | |
Electronics Forum | Tue Jan 03 05:08:50 EST 2006 | Rob
Yes - as they flex less due to their size. I do have the calculations somewhere from my field apps days but it may take some time to find. The problems occuring with the X7R's MU
Technical Library | 2011-10-20 22:03:30.0
Results of FEM modelling of thermal stress analysis in printed circuit boards are given in the article. It is shown that thermal stress alone is not solely caused by differences in coefficients of thermal expansion of individual layers. The emergence of thermal stress is subject to both the layered structure of the wall and given boundary conditions, as well as the existence of a temperature gradient in the direction normal to the surface of the wall. A practical application focuses on the issue of recycling of PCB with the effort to achieve separation of layers due to thermal stress. Role modelling of thermal stress in this area lies in predicting the possibility of separation, depending on the type of thermal stress and material parameters.
Technical Library | 1999-07-21 08:49:49.0
As the role of direct-chip-attachment increases in the electronics industry, the reliability and performance of COB packaging materials becomes an increasing concern. Although many factors influence component reliability, the biggest determinants of performance are often the glass transition temperature (Tg) and the coefficient of thermal expansion (CTE) of the encapsulant or underfill. This paper discusses exactly what these properties are, how they are measured, and why they are important to device-reliability.
Modelling of Thermal Stresses in Printed Circuit Boards Modelling of Thermal Stresses in Printed Circuit Boards Results of FEM modelling of thermal stress analysis in printed circuit boards are given in the article. It is shown that thermal
Surface Mount Technology Association (SMTA) | https://www.smta.org/knowledge/proceedings_abstract.cfm?PROC_ID=4722
, 2.5D applications include interposers of distinctly different materials, such as Si or glass. The different properties of these materials such as coefficient of thermal expansion, affect the thermomechanical response of the package to temperature excursions and the lifetime of the package
Imagineering, Inc. | https://www.pcbnet.com/blog/causes-of-pcb-warping-how-to-prevent-it/
– when heated to extremely high temperatures, thermal expansion causes movement in the direction of that stress. PCB board layers thus need to account for this movement in a balancing act
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