Long life reliability

R. Ghaffarian, Long-life Reliability of CSP Assemblies with and without Underfill, The Proceedings of Surface Mount International, (Chicago), Sept 22-26, 2002... 

The long life and reliability of tantalum equipment in severe-corrosion applications often more than offsets its higher initial costs. Therefore, a new situation has been created for utilising the benefits of tantalum products. When tantalum is properly applied, it can often be justified not only on a field replacement basis but also on initial installation. 

The provision of a small refrigerator is attractive, but the device must be of long life (several years), very reliable and low in power consumption, weight and vibration. The alternative is to provide a store of cryogenic liquid, but the experiment then has a comparatively short lifetime. Both methods are, in fact, used. 

The actual current drain that these batteries can support is low and is limited by the point defect population. However, the cell has a long life and high reliability, making it ideal for medical use in heart pacemakers. 

Mechanical and Chemical Stability. The materials must maintain their mechanical properties and their chemical structure, composition, and surface over the course of time and temperature as much as possible. This characteristic relates to the essential reliability characteristic of energy on demand. Initially, commercial systems were derived from materials as they are found in nature. Today, synthetic materials can be produced with long life and excellent stability. When placed in a battery, the reactants or active masses and cell components must be stable over time in the operating environment. In this respect it should be noted that, typically, batteries reach the consumer 9 months after their original assembly. Mechanical and chemical stability limitations arise from reaction with the electrolyte, irreversible phase changes and corrosion, isolation of active materials, and local, poor conductivity of materials in the discharged state, etc. 

The NiCd secondary battery is the most popular alkaline secondary battery, and it is available in several cell designs and in a wide range of sizes. It is a very reliable, sturdy, long-life battery, which can be operated effectively at relatively high discharge rates and over a wide temperature range. 

The system will have an extremely long life cycle and high reliability, allowing it to be placed where frequent maintenance is not possible. 

Heat engines for conversion of solar energy to electric power ideally should have lhe following attributes (1) low cost per kilowatt output capacity (2) long life and reliable operation with minimal maintenance (3) safe and environmentally acceptable operation (4) characteristics compatible with cycle top temperatures up to 1,000 K and (5) efficiency approaching Carnot values. 

The demand for reliability of the analyses, a long-life of the electrodes and their readiness to be used any time (for so-called Stat samples) directly dictated the design of ISSs/GSSs. Instead of macroelectrodes, a large variety of microelectrodes have been developed [26]. 

Reifenschweiler, 0. A High Output Sealed-Off Neutron Tube with High Reliability and Long Life. The 1968 International Conference Modern Trends in Activation Analysis, Gaithersburg, Maryland, October 7—11, 1968, Paper 20. 

High-purity aluminum has excellent corrosion resistance. Information collected over the years from manufacturers and users has shown that aluminum structures will provide reliable service for periods in excess of 30 yr. The factor that assures the long life of aluminum is a self-forming microscopically thin surface layer of aluminum oxide. The air-formed film on new aluminum surfaces is about 2.5 nm thick, while the film on aluminum that is several years old may be 10 nm thick or more. The film is composed of two parts ... 

Reliable Long Life Pump-Check-Valves... 

Well-proven, reliable design. With no moving parts, and well-chosen materials of construction the HTC reactor has a demonstrated long life and low maintenance demands. Many licensees have achieved onstream factors of 98% exclusive of programmed plant turnarounds. 

ARCO Chemical Co. Ethyl tertiary butyl ether (ETBE) Mixed C5s streams and ethanol Reliable, flexible design with high conversion and long-life catalyst 7 1995... 

While the normal criteria for materials selection address design life, sometimes other criteria govern. Examples include using design conditions rather than operating conditions as the basis for materials selection, requirements for unusual reliability or unusually long life, and corrosion debris or product contamination concerns. Such information is sometimes referred to as the materials selection design basis. It is helpful to indicate this information in the Notes addendum of the template. 

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