Thermally Managed � Heat Dissipating PCB�s (Printed Circuit Boards) By STABLCOR Corporation STABLCOR TM Printed Circuit Board Material Product Information STABLCOR Corporation has developed a new printed circuit board technology that has the followin
Electronics Forum | Fri Jun 02 15:53:51 EDT 2000 | James Burrell
I'm considering using Delmat, or some equivalent material, as a stiffener for rather large pcb, but I don't know the material properties. Specifically I'm interested in: Young's Modulus, E Poisson Ratio, nu Density, rho Strength, Thanks, Jim
Electronics Forum | Thu Jun 04 02:16:43 EDT 2020 | SMTA-Robert
Looking for CTE and young's modulus values for aluminum backed PCB for solder joint predictions. The data sheets are a bit sparse, and the weighted average method somehow doesn't feel appropriate. Any advice is welcome. Thanks!
Technical Library | 2018-08-15 17:27:28.0
Smartphones and tablets require very high flexibility and severe bending performance ability of the flexible printed circuits (FPCs) to fit into their thinner and smaller body designs. In these FPCs, the extraordinary highly flexible, treated rolled-annealed (RA) copper foils have recently used instead of regular RA foil and electro deposited foils. It is very important to measure the Young's moduli of these foils predicting the mechanical properties of FPCs such as capabilities of fatigue endurance, folding, and so on. Even though the manufacturers use IPC TM-650 2.4.18.3 test method for measuring Young's modulus of copper foils over many years, where Young's modulus is calculated from the stress–strain (S–S) curve, it is quite difficult to obtain the accurate Young's modulus of metal foils by this test method.
Technical Library | 2016-10-20 18:13:34.0
Pad cratering failure has emerged due to the transition from traditional SnPb to SnAgCu alloys in soldering of printed circuit assemblies. Pb-free-compatible laminate materials in the printed circuit board tend to fracture under ball grid array pads when subjected to high strain mechanical loads. In this study, two Pb-free-compatible laminates were tested, plus one dicycure non-Pb-free-compatible as control. One set of these samples were as-received and another was subjected to five reflows. It is assumed that mechanical properties of different materials have an influence on the susceptibility of laminates to fracture. However, the pad cratering phenomenon occurs at the layer of resin between the exterior copper and the first glass in the weave. Bulk mechanical properties have not been a good indicator of pad crater susceptibility. In this study, mechanical characterization of hardness and Young’s modulus was carried out in the critical area where pad cratering occurs using nano-indentation at the surface and in a cross-section. The measurements show higher modulus and hardness in the Pb-free compatible laminates than in the dicy-cured laminate. Few changes are seen after reflow – which is known to have an effect -- indicating that these properties do not provide a complete prediction. Measurements of the copper pad showed significant material property changes after reflow.
SMTnet Express, August 16, 2018, Subscribers: 31,259, Companies: 11,015, Users: 25,092 Reliable Young's Modulus Value of High Flexible, Treated Rolled Copper Foils Measured by Resonance Method Kazuki Kammuri, Atsushi Miki, Hiroki Takeuchi; JX
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