Inactive filler materials often require prior metallization of the ceramic substrate to provide for enough wetting, so an interface (usually reactive) is formed. Physical Vapor Deposition (PVD), Chemical Vapor Deposition (CVD), or mechanical metallization can be used to deposit metallic films such as molybdenum, manganese, tungsten, or their combination onto ceramic surfaces prior to brazing. This additional metallization step can complicate the brazing process and makes quality control of the joint more difficult.
(Implantable Neural Prostheses 2: Techniques and Engineering Approaches, Zhou D., Greenbaum E., Page: 37)
Inactive Fillers (new-better) (ingredients of plastic materials)
lnactive fillers are used mainly to reduce costs,
whereas active fillers bring about a special change in
properties so that the compound meets the require-
ments demanded of it; however, in reality, there is
no filler that is fully inactive and reduces costs
only.
Some reinforcing fillers function by forming
chemical bonds with the polymer. Others produce
enhancements in mechanical properties by taking up
volume; they bind to nearby polymer chains,
decreasing polymer chain mobility and increasing
polymer orientation at the filler surface. The in-
creased orientation results in increased stiffness,
lower deformability, and increased strength. Re-
duced mobility results in higher glass transition
temperature. Another effect that some tillers
have is on crystallinity by promoting nucleation.
Particle size and shape as well as derived
properties like specific surface and particle packing
are the most significant factors affecting the me-
chanical charactcristics of a compound. In addition
porosity and tendency to agglomeration (weak
bonding) and/or aggregation can have important
effects both on processing behavior and mechanical
properties.
(Handbook of Thermoplastic Elastomers, Jiri George Drobny, 2007, page: 20)
2) Design Analysis (old-better)
Design Analysis is comprises all the calculations necessary
to ensure a product design is optimised in terms of performance,
materials used and costs. Analysing design for materials usage can
involve carrying out out various forms of stress calculations. These may
be basen on the elastic behaviour of materials, on plastic behaviour of
materials or on a materials tendency to develop cracks. Parts and
assembliesof parts may also be analysed for stress or deflectionsby
finite element or finite difference techniques. Cost analysis may
involve comparing design which exploit the properties of particular
materials in particular ways. Performance analysis may include the
evaluation of fluid flows in the spaces not filled by material and the
evaluation of the vibrational behaviour of a product in response to
different excitation frequencies. (Roger HANNAM, Computer Integrated Manufacturing From Concepts to Realisation, 1st Edition, p. 46)
Design Analysis (new) (Analysis)
One way of gaining insight into the process of designing is by analyzing existing work. Such analyses we designate with the term ''design analysis.'' If designing is a creative process that produces something that did not exist previously, analysis begins with the outcome of that process and then attemps to get at underlying ideas and principles. This analysis, it should be pointed out, is predicated on hypothesis, it is not our intention to reconstruct the design process.
Analysis is a means of developing insight into the profession, yet it can also prove useful when researching a given site, a building to be converted or a urban area to be transformed. Though the results of a design analysis can take the form of a written text, in most eases this will be accompanied by drawings, models and computer simulations. In making an analysis it is not our task to faithfully reproduce the object under scrutiny but rather to examine those of it components crucial to the analysis such as its composition, the relationship between design and context, and that between design, construction and usefulness.
(Design and Analysis, Bernard Leupen, 1997, page: 18)
3) Chip Processing (old-better)
To most, chip-processing equipment is a necessary option; to others, they are a luxury. However, as continuous improvement programs go enterprise-wide, and global competition makes even fractional cost savings critical, efficient chip processing and coolant conservation will become more important. Add to this the implementation of far-reaching environmental initiatives, and the processing equipment becomes necessary. That is why devices that can dry chips with 98–99 percent (by weight) of the residual coolant removed, and can increase density and decrease volume, and automatically handle and remove chips from the factory floor to staging areas for transport to scrap dealers, smelters, and recycling centers are becoming more critical to plant operations. Configurations include continuous feed units for use after discharge from central filters or batch loaded processing machines for applications with at-the-machine coolant and chip separation. Various processing equipment are available and include gravity draining of fluids, drying by spinning or wringing, and making chip volumes denser through compression and compacting. With these auxiliary machines, it may sometimes be difficult to justify the financial investment in such equipment because the goal may be long term. Organizations should, however, expect more efficient chip handling and transport, reduced storage and labor needs, and also safer operations and lower environmental concerns when chip processing equipment is employed. (Geng H., Manufacturing Engineering Handbook, p. 43.8)
Chip Processing (new) (manufacturing technology)
Flip
chip processing holds the promise of being the
only high density. high performance interconnect
process to be lower in cost and higher in reliability
than wire bonding. This approach provides fast,
high volume assembly. reduces electrical losses.
reduces the interconnect interfaces (higher
reliability), and is conducive to repair.
(Manufacturing Science and Technology Area Plan, FY 94: Air Force Material COMMAND, DIANE Publishing Company, 1994, page: 16)
--In-die resistance welding has lately achieved a large popularity. Years ago, nobody even dared to think about attaching a spot welder to the progressive die and produce welded assemblies right there, automatically. But then, we must realize that years ago, sensors were not as common as they are nowadays, and without sensors in-die welding may not be possible.
--Sensors in the in-die welding process are necessary to ensure a total protection to the die. A thorough monitoring of parts’ feed length, die components’ position, scrap removal, and the overall die function as combined with the control of the moving strip, is essential. The welded-on objects must be monitored for their proper positioning within the die to make sure the welding electrode will engage the material right where it was planned and exactly the way it was planned.
--The amount of pressure the upper electrode exerts toward the assembly-to-be-welded must be carefully monitored as well, and this information must be reported back to the PLC controller. This pressure is necessary not only to hold the parts in place, but to provide for a firm contact of the two, so that welding can occur. Without a positive contact of the components, a resistance weld is very difficult to produce. As can be easily imagined, oil, grease, or dirt on the surfaces may impair the weld quality.
(Ivana Suchy, Handbook of die design , page 507)
In-Die Welding (new)
A form of forge welding generally confined to sheet metal.
Application range STEEL
The process achieves overlapping of the metal sheets, using heated dies which
hold the sheets together during welding. This is, therefore, a form of forge
welding, where the heat to raise the metal temperature is by conduction from
the dies. The necessary pressure to cause the weld is applied by conventional
means to the heated dies. Described fully under Forge Welding in Part Two
Welding.
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