Technical Library | 1999-08-27 09:29:49.0
Contract packaging houses have to contend with a large mix of die types and products. Flexibility and quick turnaround of package types is a must in this industry. Traditional methods of die encapsulation, (i.e., use of transfer-molding techniques), are only cost effective when producing a large number of components. Liquid encapsulants now provide similar levels of reliability1, and are cost effective...
Technical Library | 2021-03-04 15:22:33.0
Copper clad laminates (CCLs) with low dissipation factor (Df) are urgently needed in the fields of high-frequency communications devices. A novel resin matrix of modified poly (2,6-dimethyl-1,4- phenylene ether) (MPPE) and styrene-ethylene/butylene-styrene (SEBS) was employed in the fabrication of high-frequency copper clad laminates (CCLs). The composites were reinforced by E-glass fabrics, which were modified with phenyltriethoxysilane (PhTES). The composite laminates obtained exhibited impressive dielectric loss of 0.0027 at 10 GHz when the weight ratio of MPPE to SEBS was 5:1.
Technical Library | 2015-02-05 20:25:41.0
In the past 20 yrs the solvent industry has gone through a great deal of change. In the early 1990s, CFC-113 and 1,1,1-trichloroethane were the workhorses of the industry. The Montreal Protocol to phase-out substances that deplete the Earth's protective Ozone Layer was implemented in the mid 1990s. After phase-out of the CFC solvents, the solvent industry fragmented to a variety of cleaning solutions. The electronics industry was a large user of CFC solvents and many of these applications changed to aqueous based cleaners (...) But those alternatives are now facing various problems: e.g. aqueous based cleaners use a lot of energy, require long drying times, use equipment that requires frequent maintenance, and require a large footprint; no-clean fluxes leave flux residues; and trichloroethylene and n-propyl bromide have toxicity issues. In response to these serious issues newer solvents and blends are being introduced in the marketplace
Technical Library | 2019-02-25 05:24:53.0
"The idea of the value chain is based on the process view of organizations, the idea of seeing a manufacturing (or service) organization as a system, made up of subsystems each with inputs, transformation processes and outputs".[1] The definition of a value-added chain by Michael E. Porter is one of many to be found in reference books, works and on websites. In principle, it involves a sequence of activities, executed by a manufacturing company to develop, produce, sell, ship, and maintain products or services. Three main parameters essentially influence a value-added chain: Direct activities − research, development, production, shipment etc. Indirect activities − maintenance, operation, occupational safety, environment etc. Quality assurance − monitoring, test/inspection; quality management etc. In particular, indirect activities and quality assurance generate a greater part of the costs in product manufacturing. This article principally focusses on the indirect activities, among them air purification.
Technical Library | 2023-06-14 01:09:26.0
In the electronic packaging industry, it is important to be able to make accurate predictions of board level solder joint reliability during thermal cycling exposures. The Anand viscoelastic constitutive model is often used to represent the material behavior of the solder in finite element simulations. This model is defined using nine material parameters, and the reliability prediction results are often highly sensitive to the Anand parameters. In this work, an investigation on the Anand constitutive model and its application to SAC solders of various Ag contents (i.e. SACN05, with N = 1, 2, 3, 4) has been performed. For each alloy, both water quenched (WQ) and reflowed (RF) solidification profiles were utilized to establish two unique specimen microstructures, and the same reflow profile was used for all four of the SAC alloys so that the results could be compared and the effects of Ag content could be studied systematically.
Technical Library | 2015-03-19 20:33:34.0
Silicon is arguably the best electronic material, but it is not a good optoelectronic material. By employing first-principles calculations and the cluster-expansion approach, we discover that hydrogenated bilayer silicene (BS) shows promising potential as a new kind of optoelectronic material. Most significantly, hydrogenation converts the intrinsic BS, a strongly indirect semiconductor, into a direct-gap semiconductor with a widely tunable band gap. At low hydrogen concentrations, four ground states of single- and double sided hydrogenated BS are characterized by dipole-allowed direct (or quasidirect) band gaps in the desirable range from 1 to 1.5 eV, suitable for solar applications. At high hydrogen concentrations, three well-ordered double-sided hydrogenated BS structures exhibit direct (or quasidirect) band gaps in the color range of red, green, and blue, affording white light-emitting diodes. Our findings open opportunities to search for new silicon-based light-absorption and light-emitting materials for earth-abundant, high efficiency, optoelectronic applications.Originally published by the American Physical Society
Technical Library | 2024-08-27 06:17:52.0
销售经理 电子邮件 WhatsApp Skype 乌娜 sales5@mooreplc.com 86-15359408275 +8615359408275 品牌/制造商： ◤ PU515A 3BSE032401R1 ◥ PU515A 的特性： MB300 双运河：使用 MB300 协议进行通信的运河，可能会连接到其他控制系统。 密码：PU515A 的最终目的是实现 PU515、PU518 或 PU519 的前模型。 由于 USB 端口：RTA 与其他表的区别，PU515A 不包括 USB 端口。 为什么选择我们 1.100％原装产品，100％质量保证，价格更具竞争力。 如果您发现假货，请立即联系我们！我们承担运费！我们将免费为您寄送新产品！ 2.周到的服务 专业的售后服务。 3. 快速发货 我们有大量库存，可以立即发货。 推荐型号 本利内华达 330500-01-04 普罗软件 MVI94-MCM 本利内华达 330780-50-00 霍尼韦尔 05701-A-0301 本利内华达 330104-00-06-10-02-00 霍尼韦尔 FC-电源-UNI2450U 本利内华达 9571-50 普罗软件 MVI46-MNET 本利内华达 177230-00-01-05 霍尼韦尔 05704-A-0135 本利内华达 330180-51-CN ICS T8110B 通用电气 IC697ACC701 伍德沃德 8273-1011 本利内华达 136188-02 ABB HIEE300867R0001 PPB022 DE01 通用电气 IC695ETM001 特利科奈斯 3603E 易宝 PR6424/000-030 CON021 霍尼韦尔 51198685-100 SPS5710-2-LF 霍尼韦尔 CC-TUIO31 51306875-176 通用电气 DS200PTCTG1BAA 福克斯堡 FBM201 P0914SQ 通用电气 UR8LH 通用电气 IS210HSLAH1ADE 霍尼韦尔 CC-PAIH02 51405038-375 霍尼韦尔 51198947-100F 易宝 PR9268/200-000
Technical Library | 2023-03-16 18:51:43.0
Conductive anodic filament (CAF) formation was first reported in 1976.1 This electrochemical failure mode of electronic substrates involves the growth of a copper containing filament subsurface along the epoxy-glass interface, from anode to cathode. Despite the projected lifetime reduction due to CAF, field failures were not identified in the 1980s. Recently, however, field failures of critical equipment have been reported.2 A thorough understanding of the nature of CAF is needed in order to prevent this catastrophic failure from affecting electronic assemblies in the future. Such an understanding requires a comprehensive evaluation of the factors that enhance CAF formation. These factors can be grouped into two types: (1) internal variables and (2) external influences. Internal variables include the composition of the circuit board material, and the conductor metallization and configuration (i.e. via to via, via to surface conductor or surface conductors to surface conductors). External influences can be due to (1) production and (2) storage and use. During production, the flux or hot air solder leveling (HASL) fluid choice, number and severity of temperature cycles, and the method of cleaning may influence CAF resistance. During storage and use, the principal concern is moisture uptake resulting from the ambient humidity. This paper will report on the relationship between these various factors and the formation of CAF. Specifically, we will explore the influences of printed wiring board (PWB) substrate choice as well as the influence of the soldering flux and HASL fluid choices. Due to the ever-increasing circuit density of electronic assemblies, CAF field failures are expected to increase unless careful attention is focused on material and processing choices.
Technical Library | 2023-03-13 19:27:13.0
10%) and mean strains (>30%). A trace width effect is found for the fatigue behavior of 1 mm vs 2 mm wide specimens. The input specimen-characteristic curves are trace-width dependent, and the model predicts a decrease in Nf by a factor of up to 2 for the narrower trace width, in agreement with the experimental results. Two different methods are investigated to generate the rate of normalized resistance increase curves: uninterrupted fatigue tests (requiring ∼6–7 cyclic tests), and a single interrupted cyclic test (requiring only one specimen tested at progressively higher strain amplitude values). The results suggest that the initial decrease in normalized resistance rate only occurs for specimens with no prior loading. The minimum-rate curve is therefore recommended for more accurate fatigue estimates.
Technical Library | 2023-12-18 21:07:29.0
Selective soldering utilises a nozzle to apply solder to components on the underside of printed circuit boards (PCBs). This nozzle can be moved to either perform dips (depositing solder to a single component) or draws (applying solder to several components in a single movement). The selective soldering methodology thereby allows the process to be tailored to specific joints and allows multiple nozzle types to be used if required on the circuit board. Nozzles can vary by size (internal diameter) and shape (making them suitable for different process types). This is all dictated by board design and process requirements. Selection of the nozzle type is dependent upon the product to be soldered and the desired cycle time. Examples of different nozzle types are shown here. Hand-load selective systems must be programmed with the parameters for multiple solder joints. However, many in-line systems are designed to be modular. This modularity allows for multiple solder stations with different conditions/nozzles to achieve low cycle times. Figure 1 shows the two distinct types of selective soldering systems offered by Pillarhouse International Ltd.
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