Browse Topic: Soldering

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LEAD-FREE SOLDER VALIDATION TEST PLANUSCAR40-2 (Current)11/19/2020
This guideline is applicable to existing lead solder production products that will change to lead-free solder processes to meet the ELV Directive 2000/53/EC Annex II, exemption 8B requirements. This guideline is applicable to similar products used by multiple OEM's that have the same manufacturing processes / equipment. The intent is to streamline the supplier’s environmental testing via common qualification to reduce timing, quantities, and costs.
USCAR
The Right Stuff for Aging Electronics/Intermittence/No Fault Found2019-01-18899/16/2019
For those in the avionics repair and maintenance business, the acronyms NFF (No Fault Found), NTF (No Trouble Found), and CND (Cannot Duplicate) are, unfortunately, all too familiar terms. After several decades of frustration with this illusive phenomenon, it continues to consume an enormous amount of test and diagnostic effort and is the source of considerable cost and discomfort within the multi-level avionics repair model. There are undoubtedly many causes of NFF and all of them should be addressed. The question is: Where do you start and which solution will be the most beneficial? Our particular efforts have focused on the literal or statistical analysis of NFF, recognizing that if the system’s MTBF (Mean Time Between Failure) has decreased, or if the device's NFF rate has increased with age and deterioration, a physical fault is most likely present. However, if it isn’t found during conventional testing then it probably only fails intermittently. Similarly, having an intermittent failure mode, it in all probability cannot be detected or diagnosed at testing time because of known and demonstrated limitations in the conventional measurement equipment used to perform the tests. In this paper we will outline the problem of intermittence and its testing difficulties. More importantly, we will describe the unique equipment and process which has produced overwhelming success in Intermittence / NFF resolution and MTBF extension. Our team-developed overhaul system called IFDIS 2.0 (Intermittent Fault Detection and Isolation System 2.0) incorporates all the necessary testing procedures and technological capabilities that are proving to be critical to the resolution of the chronic intermittent / NFF problem.
Knudsen, Hector I.
Reliability Physics Approach for High-Density Ball Grid Arrays in Autonomous Vehicle Applications2019-01-12514/2/2019
Integration of advanced sensing systems in autonomous vehicles is possible due to high performance processors that utilize high-density ball grid array (HD-BGA) packaging. The configuration of advanced sensors within autonomous vehicles requires the placement of processing modules within non-conventional vehicles compartments that can drastically influence the reliability of HD-BGAs. Durability of HD-BGAs to different loads depend on their location within the vehicle as well as the form factor of the package itself. Reliability Physics Approach (RPA) combines simulation tools and empirical models to predict the reliability of advanced electronic packages under complex environmental and operational loads by identifying the susceptibility of electronic components to the dominant failure mechanism. In this paper, the reliability of an electronic module will be investigated under various vibration loads at different vehicle compartments and the influence of mounting configuration of electronic module to housing under thermal loads. In addition, the BGA form factor will be investigated to demonstrate the implementation of RPA early in the design process to develop such mitigation techniques as underfill selection to improve the reliability of HD-BGAs in autonomous vehicle applications.
Serebreni, Maxim, Sharon, Gil, Blattau, Nathan, Hillman, Craig
SoldersJ473_201808 (Current)8/24/2018
The choice of the type and grade of solder for any specific purpose will depend on the materials to be joined and the method of applying. Those with higher amounts of tin usually wet and bond more readily and have a narrower semi-molten range than lower amounts of tin. For strictly economic reasons, it is recommended that the grade of solder metal be selected that contains least amount of tin required to give suitable flowing and adhesive qualities for application. All the lead-tin solders, with or without antimony, are usually suitable for joining steel and copper base alloys. For galvanized steel or zinc, only Class A solders should be used. Class B solders, containing antimony usually as a substitute for some of the tin or to increase strength and hardness of the filler metal, form intermetallic antimony-zinc compounds, causing the joint to become embrittled. Lead-tin solders are not recommended for joining aluminum, magnesium, or stainless steel. Permissible impurity levels are shown: In dipping solders, 0.5% max copper is permissible because of pickup in bath. Compositions, temperatures, and similar specifications of these SAE solders are shown in Table 1.
Metals Technical Committee
Welding, Brazing, and Soldering - Materials and PracticesJ1147_201801 (Current)1/9/2018
The Joint AWS/SAE Committee on Automotive Welding was organized on January 16, 1974, for the primary purpose of facilitating the development and publication of various documents related to the selection, specification, testing, and use of welding materials and practices, particularly for the automotive and related industries. A secondary purpose is the dissemination of technical information.
Metals Technical Committee
Impact Mechanism of Multiple Major Welding Parameters on Mechanical Properties of Laser Brazing Lap Joint of Galvanized Steel for Vehicle2017-01-50109/22/2017
In order to research the effect of process parameters (laser power, welding speed, wire-feed speed, spot diameter) on mechanical properties of Zn-coated Steel Laser Brazing Lap Joint for vehicle, the influence of welding parameters on energy input of brazing seam cross section was theoretically analyzed, and then a great number of laser brazing experiments of 0.7mm galvanized steel was carried out. After that, the tensile strength and micro-hardness tests were also done for well-formed joints of galvanized steel formed in the laser brazing. The results show that joints with good mechanical properties and surface morphology can be formed when laser power is in the range of 2500-3200W and the other parameters keep in a specified range. Joint performance significantly reduces when the value of wire-feed speed exceeds 3.0m/min for that a wider brazing seam cross section can’t be formed. And tensile strength of the joint drops steeply when welding speed exceeds 50mm/s, because the solid-liquid surface tension between the brazing filler metal and the base metal increases. When the spot diameter increases within the appropriate range, the decrease of the energy density slows down the cooling rate of the brazing filler metal, which makes the mechanical properties of the brazing seam maintain a good condition. Moreover, under the same welding parameters, the micro-hardness anywhere inside the weld joint is uniform, which testifies the mechanical performance of the brazing seam is safe and stable.
Liu, H.J., Zhang, X.D.
CONNECTORS, PLUG, ELECTRIC, SOLDER CONTACT, 90°, AN TYPEAS31081B (Current)6/9/2017
AE-8C1 Connectors Committee
Liquid-Metal Particles Support Heat-Free SolderingTBMG-245934/27/2016
Iowa State engineers have developed micro-sized liquid-metal particles for heat-free soldering and metal processing applications.
Hermetic Feedthroughs for Mission-Critical ElectronicsTBMG-238482/1/2016
One of the most common causes of electronics failure is moisture. Because water and electronics do not mix well, several strategies exist to protect mission-critical components from moisture and condensation. One of the most successful methods involves hermetically sealed electronics cavities enabled by moisture-blocking component assemblies such as hermetic feedthrough technology.
A Discussion on the Methods of Thermal Cycling and Power Cycling for Reliability Prediction of Solder Joints of Electronic Components2015-36-05539/22/2015
The increasing use of embedded electronics in aerospace and automotive vehicles increases the designers' concern regarding the reliability of the components as well as the reliability of their interconnections. The discussion about the most appropriate method for assessing the reliability of solder joints for a given application is an ever-present theme in the literature. Several methods of prediction have been developed for assessing the reliability of solder joints. The standard method established by the industries for assessing reliability of solder joints is the thermal cycling. However, when the thermal distributions in real applications are studied, particularly in some electronic components used in on-board electronics of space systems, the thermal cycling does not represent what actually happens in practice in the packaging. The aim of this article is to discuss the methods of thermal cycling; and power cycling for reliability prediction of solder joints of electronic components. With the power cycling you can: 1) simulate more closely the actual conditions; 2) accelerate a cycle of application when applying energy to the component, increasing junction temperature; and decreasing the junction temperature when removing energy from the component. With the thermal cycling, the solder joints and the printed circuit board are almost at the same temperature in an isothermal situation at any moment and thermal gradients within the packaging are often negligible. Fatigue data of solder joints from thermal cycling and power cycling are obtained through networks of monitoring components of type "daisy-chain" with the aid of high-speed event detectors. Both profiles are obtained and compared in the Weibull graphs. Failure data results obtained from the literature have shown that the thermal cycling in general is conservative compared with the power cycling. In addition, according to the literature, power cycling simulates better the gradients of temperature found in the packages of components in actual applications. On components of type PBGA, solder joint characteristic life was 45% longer in power cycling.
de Brito, Alirio Cavalcanti, de Oliveira e Souza, Marcelo Lopes
Predicted Device-Degradation Failure-Rate2015-01-25559/15/2015
There is a concern that the continuing trend on miniaturization (Moore's law) in IC design and fabrication might have a negative impact on the device reliability. To understand and to possibly quantify the physics underlying this concern and phenomenon, it is natural to proceed from the experimental bathtub curve (BTC) - reliability “passport” of the device. This curve reflects the combined effect of two major irreversible governing processes: statistics-related mass-production process that results in a decreasing failure rate with time, and reliability-physics-related degradation (aging) process that leads to an increasing failure rate. It is the latter process that is of major concern of a device designer and manufacturer. The statistical process can be evaluated theoretically, using a rather simple predictive model. Owing to that and assuming that the two processes of interest are statistically independent one can assess the failure rates associated with the aging process from the BTC data by simply subtracting the predicted ordinates of the statistical failure rates (SFR) from the BTC ordinates. The objective of this analysis is to show how this could be done. The suggested methodology proceeds from the concepts that the actual (“instantaneous”) SFR is a random variable with a known (assumed, established) probability distribution, that the experimental BTC can be represented by its infant mortality and the wear-out portions only (the steady-state portion in this case is simply the boundary between the infant mortality and wear-out portions) and that the two BTC portions considered can be approximated analytically. The cases, when the “instantaneous” SFR is distributed normally and in accordance with the Rayleigh law are used as suitable illustrations of the general concept. The developed methodology can be employed when there is a need to better understand the relative roles of the statistics-related and physics-of-failure-related processes in reliability evaluations of electronic products. The methodology can be used also beyond the field of IC engineering, when there is a need to understand and, hence, to separate the roles of the two irreversible processes in question. One of the major challenges of the future work is to determine the probability distributions of the actual (“instantaneous”) SFRs for particular products and applications.
Suhir, Ephraim, Bensoussan, Alain, Nicolics, Johann
Stacked Capacitor Special Lead AdapterTBMG-221866/1/2015
The current installation method for tall, stacked capacitors is very cumbersome because the lead form is very sharp and prone to solder cracking due to thermal cycling. An astringent installation process was developed to obtain the best chance of a successful solder joint with a proper heel fillet so the chance of cracking is minimized.
Lead-Free Solder Validation Test PlanUSCAR40-1 (Historical)4/22/2015
This guideline is applicable to existing lead solder production products that will change to lead-free solder processes to meet the ELV Directive 2000/53/EC Annex II, exemption 8B requirements. This guideline is applicable to similar products used by multiple OEM's that have the same manufacturing processes / equipment. The intent is to streamline the supplier’s environmental testing via common qualification to reduce timing, quantities, and costs.
USCAR
E-Textile InterconnectTBMG-216303/1/2015
E-textiles have shown great promise within the microwave and antenna community to provide a low-mass, highly conformal option that integrates extremely well with fabric-based microwave devices and antenna platforms, but often not as well with more conventional devices.
HALT Technique to Predict the Reliability of Solder Joints in a Shorter DurationTBMG-203188/1/2014
The Highly Accelerated Life Testing (HALT) process subjects test articles to accelerated combined environments of thermal, dynamic, voltage, and current to find weak links in a given product design. The technique assesses fatigue reliability of electronic packaging designs used for long-duration deep space missions by testing using a wide temperature range (–150 to +125 °C), and dynamic acceleration range of up to 50g. HALT testing uses repetitive, multiple-axis vibration combined with thermal cycling on test articles to rapidly precipitate workmanship defects, manufacturing defects, and thermal cycling-related weak links in the design. This greatly reduces the product development time by rapidly finding problems and qualifying the packaging design quickly. Test vehicles were built using advanced electronic package designs using the surface mount technology process.
SHIELD TERMINATION, SOLDER STYLE, INSULATED, HEAT-SHRINKABLE, ENVIRONMENT RESISTANT WITH PREINSTALLED BRAID,TIN PLATED, CLASS I, NON-ROHSAS83519/3 (Historical)7/8/2014
Scope is unavailable.
AE-8C2 Terminating Devices and Tooling Committee
SHIELD TERMINATION, SOLDER STYLE, INSULATED, HEAT-SHRINKABLE, ENVIRONMENT RESISTANT WITH PREINSTALLED BRAID, NI PLATED, CLASS I, ROHSAS83519/5 (Historical)7/8/2014
Scope is unavailable.
AE-8C2 Terminating Devices and Tooling Committee
Wire-to-Board ConnectorTBMG-196495/1/2014
ERNI (Richmond, VA) has developed a compact and economical wire-to-board interconnect solution with high current density in a small, 2.0mm pitch form factor. The iBridge™ single-row cable connector system delivers up to 5A per contact at 20 °C when paired with an appropriate discrete wire. The male iBridge connectors are available in right angle and vertical configurations with DIP solder termination for extra mechanical strain relief, or SMT termination with durable solder brackets for maximum PCB real estate usage and a high PCB retention force. Offered in 2, 3, 4, 5, 6, and 8 positions with additional sizes up to 12 in development, the iBridge connectors utilize crimp and poke wire terminations.
Reliability of CCGA 1152 and CCGA 1272 Interconnect Packages for Extreme Thermal EnvironmentsTBMG-163475/1/2013
Ceramic column grid array (CCGA) packages have been increasing in use based on their advantages of high interconnect density, very good thermal and electrical performance, and compatibility with standard surface-mount packaging assembly processes. CCGA packages are used in space applications such as in logics and microprocessor functions, telecommunications, flight avionics, and payload electronics. As these packages tend to have less solder joint strain relief than leaded packages, the reliability of CCGA packages is very important for short- and long-term space missions.
Circularly Polarized Microwave Antenna Element With Very Low Off-Axis Cross-PolarizationTBMG-161174/1/2013
The goal of this work was to improve offaxis cross-polarization performance and ease of assembly of a circularly polarized microwave antenna element. To ease assembly, the initial design requirement of Hexweb support for the internal circuit part, as well as the radiating disks, was eliminated.
Glass Solder Approach for Robust, Low-Loss, Fiber-to- Waveguide CouplingTBMG-147079/1/2012
The key advantages of this approach include the fact that the index of interface glass (such as Pb glass n = 1.66) greatly reduces Fresnel losses at the fiber-to-waveguide interface, resulting in lower optical losses. A contiguous structure cannot be misaligned and readily lends itself for use on aircraft or space operation. The epoxy-free, fiber-to-waveguide interface provides an optically pure, sealed interface for low-loss, highpower coupling. Proof of concept of this approach has included successful attachment of the low-melting-temperature glass to the x–y plane of the crystal, successful attachment of the low-meltingtemperature glass to the end face of a standard SMF (single-mode fiber), and successful attachment of a wetted lowmelting- temperature glass SMF to the end face of a KTP crystal.
Design, Layout, Criteria - Plastic Integrally Lighted PanelsARP498C (Current)4/4/2012
This document is intended to cover the design of plastic lighted panels, mounting plates, and their installation.
A-20A Crew Station Lighting Committee
LEAD-FREE SOLDER VALIDATION TEST PLANUSCAR40 (Historical)4/1/2011
This guideline is applicable to existing lead solder production products that will change to lead-free solder processes to meet the ELV Directive 2000/53/EC Annex II, exemption 8B requirements. This guideline is applicable to similar products used by multiple OEM's that have the same manufacturing processes / equipment. The intent is to streamline the supplier’s environmental testing via common qualification to reduce timing, quantities, and costs.
USCAR
CONNECTORS, RECEPTACLE, ELECTRIC, WALL MOUNTING, FRONT RELEASE, CRIMP CONTACT, AN TYPE - WITH ACCESSORY THREADSAS34121B (Historical)12/10/2010
AE-8C1 Connectors Committee
Connector Accessories, Electrical, Nonenvironmental, Strain Relief, Straight, Category 4A (For MIL-DTL-5015 Solder Type, V Thread of MS310X Classes A, B, C or K Connectors)AS85049/42A_A1 (Historical)4/19/2010
Amendment 1 of AS85049/42A.
AE-8C1 Connectors Committee
Connector Accessories, Electrical, Backshell, Environmental, Cable Sealing, Straight, Category 1C (For MIL-DTL-5015 Solder Type, V Thread of MS310X Classes A, B, C or K Connectors)AS85049/2A (Historical)6/29/2009
No scope available.
AE-8C1 Connectors Committee
Connector Accessories, Electrical, Backshell Environmental, Cable Sealing, Straight, Grounding (Without Strain Relief), Category 1c (For Mil-C-5015 Solder Type, V Thread of Ms310x Classes A, B. C Or K Connectors)AS85049/1A (Historical)6/29/2009
No scope available.
AE-8C1 Connectors Committee
Connector Accessories, Electrical, Backshell Environmental, Cable Sealing, Straight, Grounding (Without Strain Relief), Category 1C (For MIL-C-5015 Solder Type, V Thread of MS310X Classes A, B. C Or K Connectors)AS85049/1 (Historical)6/29/2009
No scope available.
AE-8C1 Connectors Committee
Reliability Testing and Damage Analysis of Lead-Free Solder Joints: New Assessment Criteria for Laboratory Methods2009-01-13684/20/2009
Driven by legislation in the European Union (ELV directive 2000/53/EC [1]) and international industry activities for the use of environment-friendly technologies, automotive suppliers and OEMs are faced with the demand to substitute lead-containing solders in electronic assemblies. Compared to consumer electronics, for which lead-containing technologies had to be phased out by July 2006, automotive applications have to meet considerably higher requirements concerning lifetime and environmental loading conditions, which mainly result from superimposed vibrations and temperature cycling. Therefore, advanced reliability testing and damage analysis techniques are needed to ensure a reliable use of lead-free solders. This paper presents the results of reliability tests that aimed at assessing the capabilities of different analysis tools to characterize solder joints for quality assurance and damage analysis. Detailed electric and mechanical testing as well as metallographic cross-section analysis of differently aged specimens soldered with standard SnPb and lead-free SnAgCu-solder revealed advantages and disadvantages of commonly used examination methods. The gained experiences are used to develop an approach for a new test series. The goal is to develop quantitative measures for damage analysis of solder joints via new testing methods and more elaborate examinations of common methods. On the basis of these measures a more distinct correlation of failure modes to loading conditions shall be possible.
Steller, Antje, Zimmermann, Axel, Eisenberg, Stephan, Wolter, Klaus-Juergen, Lange, Petrik
Shield Termination, Solder Style, Insulated, Heat-Shrinkable, Environment Resistant General Specification ForAS83519A_A3 (Historical)11/18/2008
Amendment 3 of AS83519A.
AE-8C2 Terminating Devices and Tooling Committee
Shield Termination, Solder Style, Insulated, Heat-Shrinkable, Environment Resistant, General Specification ForAS83519A_A2 (Historical)8/28/2008
Amendment 2 of AS83519A.
AE-8C2 Terminating Devices and Tooling Committee
Experimental Study of an Electronic Module Potting Dispensing Process2008-01-07164/14/2008
Often electrical components are encapsulated in a plastic material after assembly. The goal of this study is to determine what variables are most important in reducing potting variation and identify the key machine parameters which can be used to make adjustments to the potting process. To maximize the efficiency of testing, an L18 orthogonal array was used to structure an experiment. Hose temperature, orifice size, and pressure were found to be the most significant control factors studied in this experiment. Shifting from the initial settings for these factors to the recommended settings should increase the S/N of the potting process by 14.53db. Motor speed was found to be the most significant variable for adjusting the mean of the process. The noise factors induced in this study were found to be a significant source of variation. Filters can shift the mean potting material applied by 25% over their planned usage life. Moreover, new filters induce more variation than old filters.
Vinarcik, Edward J.
Connectors, Electrical, Circular, Miniature, High Density, Quick Disconnect (Bayonet, Threaded, and Breech Coupling), Environment Resistant, Removable Crimp and Hermetic Solder Contacts, Plug, Lanyard Release, Fail-Safe, Triple Start Threaded Coupling, Removable Crimp Contacts Sockets, Series III, MetricAS38999/30A (Current)11/6/2007
Scope unavailable.
AE-8C1 Connectors Committee
Laser Diode Market Stays Hot in 2007TBMG-1217511/1/2006
The high-power laser diode market has grown rapidly in the last twelve months, a trend that is set to continue throughout 2006 and beyond. The global market for laser systems is forecast to grow by 8% in 2006 to US $5.9 billion, with diode lasers alone growing by 8%.
CONTACTS, ELECTRICAL CONNECTORS, PIN, SOLDER, REMOVABLE, SHIELDED, SIZE 12 (FOR MIL-C-83723 SERIES III, MIL-C-26482 SERIES 2, MIL-C-83733 AND DOD-C-83527 CONNECTORS)AS39029/74 (Historical)10/4/2006
AE-8C1 Connectors Committee
CONTACTS, ELECTRICAL CONNECTORS, SOCKET, SOLDER, REMOVABLE, SHIELDED, SIZE 12 (FOR MIL-C-83723 SERIES III, MIL-C-26482 SERIES 2, MIL-C-83733, AND DOD-C-83527 CONNECTORS)AS39029/73 (Historical)10/4/2006
AE-8C1 Connectors Committee
Connector Accessories, Electrical, Nonenvironmental, Strain Relief, Straight, Category 4A (For MIL-DTL-5015 Solder Type, V Thread of MS310X Classes A, B, C or K Connectors)AS85049/42A (Historical)6/30/2006
Scope unavailable.
AE-8C1 Connectors Committee
3D- ESPI: Thermal Expansion Analysis of Electronic Components2006-01-07654/3/2006
Schubach, H., Moser, E.
Infrared Emitter Combines Photonic Crystal Technology With MEMS ManufacturingTBMG-644110/1/2005
In one of the first real-world applications of photonic crystals, two companies partnered to produce a photonic crystal enhanced (PCE) micro-hotplate device with applications in areas from military combat identification to commercial and biomedical gas sensing technology. Ion Optics, which manufactures optical-based MEMS gas detection sensors and wavelength-tuned infrared emitters, partnered with IMT, which produced the device using its MEMS prototyping and production capabilities.
Nadcap Requirements for Thermal SprayAS7109/1A (Historical)9/21/2005
This SAE Aerospace Standard (AS) is to be used as a supplement to AS7109. In addition to the requirements contained in AS7109, the requirements contained herein shall apply to suppliers seeking Nadcap Coatings accreditation who are engaged in thermal spray.
Nadcap Management Council
Shield Termination, Solder Style, Insulated, Heat-Shrinkable, Environment Resistant General Specification ForAS83519A_A1 (Historical)9/29/2004
Amendment 1 of AS83519A.
AE-8C2 Terminating Devices and Tooling Committee
Connector, Receptacle, Electric, Hermetic, Solder Type, Box Mounting, Push-Pull Coupling, Series 3 (Class H)AS34661_A1 (Historical)9/13/2004
Amendment 1 of AS34661.
AE-8C1 Connectors Committee
Connector, Receptacle, Electric, Solder Type, Box Mounting Flange, Push-Pull Coupling, Series 1 (Class E and H)AS31321_A1 (Historical)9/13/2004
Amendment 1 of AS31321.
AE-8C1 Connectors Committee
Shield Termination, Solder Style, Insulated, Heat-Shrinkable, Environment Resistant General Specification ForAS83519A (Historical)7/17/2003
This specification covers environment resistant, heat-shrinkable solder type shield terminations. They may be used on data-bus, RF and shielded cables in applications where the operating temperature does not exceed 150C.
AE-8C2 Terminating Devices and Tooling Committee
Thermomechanical Fatigue Studies on Pb-free Automotive Electronic Solders2003-01-06213/3/2003
Electronic solders used in automotive under-the-hood applications experience severe thermal excursions. Under such conditions thermomechanical fatigue (TMF) is a major concern. Aging, creep/stress relaxation, and imposed temperature-time profile have been found to be major contributors for such failures. However, in the currently popular Sn-based solders, the anisotropic behavior of Sn and reversed shear also play significant roles. Our studies evaluate the role of all these parameters, and consider the role of alloying elements and reinforcements on the TMF behavior of Sn-based solders. This paper provides an overview of this effort.
Lee, J. G., Guo, F., Subramanian, K. N.
Solder Sleeves, Heat Shrinkable, InsulatedAS939 (Current)12/16/2002
AE-8C2 Terminating Devices and Tooling Committee
Continuous Improvement Efforts in Wire Bonding2002-01-08943/4/2002
Concerns with stripping and soldering copper magnet wire in ignition coils and other related products have led to the investigation of an alternative product and process design, microjoining. This paper describes the initial development occurring during the improvement phase of a Six Sigma project. The use of microjoining with a folded over welding tab terminal design coupled with a parallel gap welding process is developed as a suitable method for joining a tin plated brass terminals to the 0.65mm magnet wire without prior removal of the polyesterimide over-coated polyamideimide insulation.
Lynch, Donald P., Fleischmann, Jay E., Duff, William S.
Development of Automotive Body Solders2001-01-308010/16/2001
Lead (Pb) based solders had been used successfully as dent and seam fillers for automotive body panels and were commonly referred to as “body solders”. The usual compositions were 70wt% Pb - 30wt% Sn or 80wt% Pb - 20wt% Sn. But due to the hazards associated with Pb dust and particles from the grinding and sanding, new lead-free body solders were developed in the early 80's. An 82wt%Sn - 15wt%Cu - 3wt%Zn composition was developed to mimic the pasty characteristics and processability of the lead-containing solders. This body solder has the advantages of corrosion resistance, compatibility with e-coat, and a lower processing temperature and lower material cost than an alternative candidate approach that uses a silicon bronze material. The ideal temperature range for applying this solder is between 280 to 350°C, which provides a workable, viscous material. This temperature range is much lower than the MIG welding temperature of the silicon bronze material and results in much less heat distortion of the steel panels. The microstructure is a dendritic structure with a Cu6Sn5 intermetallic compound in a Sn-rich matrix. The spacing of the dendrites can be reduced with a small addition of Fe. A zinc chloride (ZnCl2) and ammonium chloride (NH4Cl) based flux or tinning paste is required to clean the oxide surface. Any residual flux residue was found to be fully compatible with the phosphate process in a paint compatibility study. There appears to be great potential if such an automated process is implemented.
Pan, Tsung-Yu, Blair, Howard D., Nicholson, John M., Gickler, Alan E.
Design, Layout, Criteria — Plastic Integrally Lighted PanelsARP498A (Historical)10/1/2001
This document is intended to cover the design of plastic lighted panels, mounting plates, and their installation.
A-20AC Crew Station and Interior Lighting Committee
Across-Gimbal Ambient Thermal Transport System2001-01-21957/9/2001
This paper describes the development, operation and testing of an across-gimbal ambient thermal transport system (GATTS) for carrying cryocooler waste heat across a 2-axis gimbal. The principal application for the system is space-based remote sensing spacecraft with gimbaled cryogenics optics and/or infrared sensors. GATTS uses loop heat pipe (LHP) technology with ammonia as the working fluid and small diameter stainless steel tubing to transport 100–275 W across a two-axis gimbal. The tubing is coiled around each gimbal axis to provide flexibility (less than 0.68 N-m [6 lbf-in] of tubing-induced torque per axis) and fatigue life. Stepper motors are implemented to conduct life cycling and to assess the impact of motion on thermal performance. An LHP conductance of approximately 7.5 W/C was demonstrated at 200 W, with and without gimbal motion. At the time this paper was written, the gimbal had successfully completed over 500,000 cycles of operation with no performance degradation.
Marland, B., Yun, J., Bugby, D., Stouffer, C., Tomlinson, B., Davis, T.
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