Zymet's underfill encapsulants for flip chips are designed to enhance the thermal cycle performance. They incorporate silica filler, used to reduce the encapsulant’s CTE, that are highly engineered in both morphology and particle size distribution to
Thermodime� diamond heat transfer compound from Electrospell is an ultra high thermal conductivity thermal interface material composed of pure surface-modified diamond microcrystals suspended in a special carrier fluid. The product comes in a 1 ml sy
Electronics Forum | Tue Dec 30 20:48:31 EST 1997 | Tom Gervascio
Has anyone had any experience with thermal shocking and cracking of SMD capacitors during the rework process? My company was advised to preheat capacitors to 125 C at a rate of 2 C/sec before replacing them onto boards. Would this maybe degrade c
Electronics Forum | Thu Feb 11 08:14:41 EST 2010 | scottp
It's OK to have the daisychain done in the interposer rather than the die (and a lot cheaper) but in thermal cycling the parts MUST have representative die. That's where a large part of the CTE mismatch comes from to cause fatigue damage. Thermal c
Used SMT Equipment | Soldering - Reflow
Features 1. Full hot air reflow heat fast, high thermal efficiency compensation, delta t less than ± 2 ℃ soldering is uniform. 2. HELLER company has 40 years of history, process maturity. 3. maintenance costs low, the furnace normal use, electrici
Industry News | 2018-04-22 19:12:45.0
SMTA Europe announces Session 7 Technical Program on High Temperature PCB Materials and Fabrication at the “Electronics in Harsh Environments Conference” to be held in Amsterdam, Netherlands, on April 25th, 2018.
Industry News | 2010-04-30 18:47:15.0
SMTA China announces that it presented awards for the 10 best papers/presentations and two best exhibits at the SMTA China East 2010 Conference Award Presentation Ceremony, held on Wednesday, April 21, 2010 at the Shanghai Everbright International Hotel in conjunction with the SMTA China Annual Breakfast Reception.
Technical Library | 2024-08-09 06:34:09.0
Quality control in conformal coating applications is vital for ensuring the reliability and longevity of electronic products. Conformal coatings protect printed circuit boards (PCBs) from environmental factors like moisture, dust, and chemicals. To maintain high standards, various inspection methods are employed throughout the coating process. Visual Inspection This is the first line of defense against defects. Inspectors look for uniform coverage, absence of bubbles, and proper curing. Training is essential to ensure that inspectors can identify subtle issues that may affect performance. UV Inspection Most conformal coatings contain a UV tracer, which makes the coating visible under ultraviolet light. UV inspection allows for easy detection of missed areas, ensuring complete coverage. This step is crucial for verifying that the coating has been applied correctly, especially in hard-to-see areas of the PCB. Automated Optical Inspection (AOI) AOI systems offer a more precise and consistent method for inspecting conformal coatings. They use cameras and specialized software to detect defects that might be missed by the human eye. AOI systems can inspect large volumes of PCBs quickly, making them ideal for high-production environments. Thickness Measurement The thickness of the conformal coating is critical for providing adequate protection without affecting the performance of the PCB. Tools such as micrometers, ultrasonic thickness gauges, and eddy current devices are used to measure the coating thickness. Consistent application is key to preventing issues like cracking or insufficient protection. Functional Testing Beyond visual and automated inspections, functional testing is necessary to ensure that the conformal coating does not interfere with the electrical performance of the PCB. This involves subjecting the coated PCB to environmental stress tests, such as thermal cycling, humidity, and salt spray, to assess its reliability in real-world conditions. Process Control and Documentation Implementing strict process controls is essential to maintaining quality. This includes regularly calibrating equipment, training operators, and documenting every step of the process. Proper documentation helps trace issues back to their source and prevents them from recurring. Conclusion Effective quality control in conformal coating applications ensures that PCBs are protected from environmental damage, thereby extending their lifespan and reliability. By employing a combination of visual, UV, and automated inspections, along with thickness measurement and functional testing, manufacturers can achieve the highest standards in coating quality.
Technical Library | 2022-12-05 16:28:06.0
The work evaluates the impact of latent heat (LH) absorbed or released by a solder alloy during melting or solidification, respectively, on changes of dimensions of materials surrounding of the solder alloy. Our sample comprises a small printed circuit board (PCB) with a blind via filled with lead-free alloy SAC305. Differential scanning calorimetry (DSC) was employed to obtain the amount of LH per mass and a thermomechanical analyzer was used to measure the thermally induced deformation. A plateau during melting and a peak during solidification were detected during the course of dimension change. The peak height reached 1.6 μm in the place of the heat source and 0.3 μm in the distance of 3 mm from the source. The data measured during solidification was compared to a numerical model based on the finite element method. An excellent quantitative agreement was observed which confirms that the transient expansion of PCB during cooling can be explained by the release of LH from the solder alloy during solidification. Our results have important implications for the design of PCB assemblies where the contribution of recalescence to thermal stress can lead to solder joint failure.
Events Calendar | Mon Apr 23 00:00:00 EDT 2018 - Thu Apr 26 00:00:00 EDT 2018 | Shanghai, China
SMTA China East Conference 2018
Career Center | , District of Columbia | Engineering,Management,Production,Sales/Marketing
• Strong technical leadership and decision-making skills; strong verbal and written communication skills to provide clear, crisp direction for key issue resolution; and good team skills to facilitate cross-functional cross -site team effectiveness.
SMTnet Express, December 23, 2015, Subscribers: 23,927, Members: Companies: 14,845, Users: 39,621 PCB Fabrication Processes and Their Effects on Fine Copper Barrel Cracks Edward Arthur, Charles Busa, Melissa Durfee, Chad Gibson, Wade Goldman P