Technical Library | 2019-11-12 02:09:22.0
Thermal shock test chamber can be used for testing the chemical change or physical damage on composite materials caused by the thermal expansion and contraction of the sample in the shortest time,which is subjected to extremely and continuous high and low temperature environment.so how to check the temperature recovery time of this chamber? Normally we take following steps to inspect the temepratuire recovering time: 1.Install the temperature sensor at the specified position, and adjust the temperature controller of hot zone and cold zone to the required nominal temperature respectively. 2.The temperature increases and reduces respectively,30min after temperature in two zones reach stable status,record temperature value of the measuring point,pls set the temperature value of two zones to be required nominal temperature. 3.The temperature shock test chamber automatically places the inspected load into theh ot zone,select the corresponding retention time according to regulated standard. 4.Set the transfer time,then the inspection load is transferred from hot zone to cold zone, and the temperature of the measuring point is observed and recorded, and then the reverse conversion of the load from cold zone to hot zone is carried out according to the same method, and the temperature of the measuring point is observed and recorded. www.climatechambers.com
Technical Library | 2010-12-22 13:59:14.0
This paper discusses polymer based nanogels, nanofluids and nanopastes for thermal interface material (TIM) applications. Nanopaste and nanogel formulated using controlled-sized particles to fill small bond lines is highlighted.
Technical Library | 2019-10-24 14:23:49.0
Presentation given by Fred Dimock during a seminar at the American Competitiveness Institute, ACI. •Recipe vs. Profile •Material Properties •Why profiles are shaped like they are. •Obtaining profiles •TC Accuracy •Profilers •Test vehicles •Process Window – Eutectic vs. Lead Free •Heat transfer •Oven Control
Technical Library | 2007-10-10 23:23:40.0
Process engineers, who are seeking to achieve the most effective and reproducible thermal transfer process, look to today's forced convection ovens for applications such as flipchip, BGA, and lead-free soldering. A forced convection process to maximize thermal uniformity can be best accomplished by employing static pressure generation in what's known as "closed loop convection".
Technical Library | 2020-05-07 03:46:27.0
The selective soldering process has evolved to become a standard production process within the electronics assembly industry, and now accommodates a wide variety of through-hole component formats in numerous applications. Most through-hole components can be easily soldered with the selective soldering process without difficulty, however some types of challenging components require additional attention to ensure optimum quality control is maintained. Several high thermal mass components can place demands on the selective soldering process, while the use of specialized solder fixtures and/or pallets often places an additional thermal demand on the preheating process. Fine-pitch through-hole components and connectors place a different set of demands on the selective soldering process and typically require special attention to lead projection and traverse speed to minimize bridging between adjacent pins. Dual in-line memory module (DIMM) connectors, compact peripheral component interface (cPCI) connectors, coax connectors and other high thermal mass components as well as fine-pitch microconnectors,can present challenges when soldered into backplanes or multilayer printed circuit board assemblies. Adding to this challenge, compact peripheral component interface connectors can present additional solderability issues due to their beryllium copper termination pins.
Technical Library | 2024-09-02 18:48:58.0
The conversion to higher temperature "Lead Free" assembly reflow conditions has created an increased awareness that entrapped or absorbed moisture is a frequent root cause of thermally induced delamination at assembly reflow. There are two connected failure modes from entrapped moisture; incomplete resin cross-linking resulting in premature resin decomposition and also severe Z axis expansion from "explosive vaporization of the entrapped moisture at elevated temperatures at assembly reflow". Ultimately, both result in delamination failure. Other papers have shown the negative effects of entrapped moisture before lamination including delamination, red color, reduced thermal reliability and increased high speed signal loss. In this paper, various materials were tested for moisture sensitivity during lamination. Tests were performed at varying lamination conditions including a pre-vacuum step and "kiss" step. Pressure and cure temperature parameters were evaluated for minimizing or eliminating the effect of trapped moisture. Also included are the results of inner layer moisture removal baking conditions and their effect on peel strength and thermal reliability.
Technical Library | 2020-06-19 19:08:14.0
The designs of electronic devices and systems are being continuously improved by becoming smaller in size and faster in communication speed. The potential risk associated with these specific design improvements will be an increase in power density and, consequently, a greater risk of thermal problems and failures. At the same time, the prevailing use of circuit boards integrated with power devices such as motor controllers and drivers, light-emitting diode (LED) lighting modules, power supplies, and amplifiers, and regulators for TV, etc., drive to the use of a proper thermal management system while designing these kinds of printed circuit board (PCB).
Technical Library | 2018-11-20 21:33:57.0
There are several industry-accepted methods for determining the reliability of flux residues after assembly. The recommended methods of test sample preparation do not always closely mimic the thermal cycle experienced by an assembly. Therefore, extraction from actual assemblies has become a popular method of process control to assess consistency of post-reflow cleanliness. Every method of post-reflow flux residue characterization will depend on the reflow process followed to prepare the coupon.This investigation will focus on the effect of thermal conditions on the remainder of active ingredients in flux residues after assembly with no-clean solder pastes.
Technical Library | 2021-05-06 13:41:55.0
Quality control is of vital importance during electronics production. As the methods of producing electronic circuits improve, there is an increasing chance of solder defects during assembling the printed circuit board (PCB). Many technologies have been incorporated for inspecting failed soldering, such as X-ray imaging, optical imaging, and thermal imaging. With some advanced algorithms, the new technologies are expected to control the production quality based on the digital images. However, current algorithms sometimes are not accurate enough to meet the quality control. Specialists are needed to do a follow-up checking. For automated X-ray inspection, joint of interest on the X-ray image is located by region of interest (ROI) and inspected by some algorithms. Some incorrect ROIs deteriorate the inspection algorithm.
Technical Library | 2021-04-21 19:28:30.0
Voids affect the thermal characteristics and mechanical properties of a solder joint, thereby affecting the reliability of the solder interconnect. The automotive sector in particular is requiring the mitigation of solder voids in various electronic control modules to the minimum possible level. Earlier research efforts performed to decrease voids involved varying the reflow profile, paste deposit, paste alloy composition, stencil aperture, and thickness.
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