Annealing(old)
Glass products usually have undesirable şnternal stresses after forming, which reduce their strength. Annealing is done to retrieve these stresses; the treatment therefore has the same function in glassworking as it does in metalworking. Annealing involves heating the glass to an elevated temperature and holding it for a
certain period to eliminate stresses and temperature gradients; then slowly cooling the glass to supress stress formation, followed by more rapid cooling to room temperatyre. Common annealing temperatures are around 500°C (900°F). The lenght of time product is held at the temperature, as well as the heating and cooling rates during the cycle, depend on thickness of the glass, the usual rule being that the required annealing time varies with the square of thickness.Annealing in modern glass factories is performed in tunnel-like furnaces, called lehrs, in which the produxtss flow slowly through the hot chamber on conveyors.
Burners are located only at the front end of the chamber, so that the glass experiences the required heating and cooling cycle.
(Groover, M.P., Fundamentals of modern manufacturing : materials, processes, and systems, Wiley Internatiol, 2002, 2nd Edition, pg. 253)
Annealing(new) [manufacturing process]
Annealing is the thermal treatment needs to erase any irradiation memory from the dosimetric material.
Some thermoluminescent material require a complex annealing procedure. It requires a high temperature anneal, followed by a low temperature anneal.
Generally speaking the high temperature anneal is required to clear the dosimetric traps of residual signal which may cause unwanted backgrounds during subsequent use of dosimeters. The low temperature anneal is required to stabilize and aggregate low temperature traps in order to enhance the sensitivity of the main dosimetry traps and to reduce losses of radiation-induced signal due to thermal or optical fading during use. The combination of these two anneals is termed standard anneal.
(Handbook of Thermoluminescence Author: Claudio Furetta p.8)
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Brinell Hardness(old)
Brinell hardness test has a hard spherical indenter which is pressed under a fixed normal load on to the smooth surface of the metal under examination. The load and indenter are removed after balance has been reached like 15 or 30 seconds and diameter of permanent impression measured. Brinell hardness number (BHN) is then expressed as the ratio of load W to curved area of indentation.
(The Hardness of Metals, D. Tabor; Page:6)
Brinell Hardness(new) [material mechanical property]
Hardness is a measure of the resistance of a material to surface indentation or abrasion. Hardness may be thought as a function of the stress required to produce some specified type of surface deformation. A Brinell Hardness number (HB) is the result of a static indentation test which a hardened steel or tungsten carbide ball is pressed into the sample surface and the size of the indentation is measured optically. HB is the ratio of the applied force to the surface area of the impression in units of kg/mm^2 as follows whre P is load(kg), D is ball diameter(mm) and d is diameter of the indentation(mm):
(ASM ready reference: properties and units for engineering alloys Author: ASM International. Materials Properties Database Committee p.66)
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Innovation(old)
Innovation is about having and applying a new idea, or sometimes applying other peoples ideas in new and novel ways. As aptly noted by Michael Vance:“innovation is the creation of the new or the re-arranging of the old in a new way.”In a mundane sense at many points in our lives, we are all innovators. The challenge arises when innovation is about an idea that is implemented successfully resulting in a positive outcome. For a firm this connected to the launching new products or improving on an existing product. Sometimes it involves organizational innovation that enhances firm efficiency. At a macro level, innovation is intimately connected to economic growth and welfare
(Sarkar S., Innovation, Market Archetypes and Outcome, 2007, p. 1)
Innovation(new) [product design]
Innovation consists of the generation of a new idea and its implementation into a new product, process, or service, leading to the dynamic growth of the national economy and the increase of employment as well as to creation of pure profit for the innovative business enterprise. Innovation is never a one-time phenomenon, but a long and cumulative process of great number of organizational decision-making processes, ranging from the phase of generation of a new idea to its implementation phase. Innovation includes both major and minor changes. It should be considered as an economical concept rahter than a technological one.
(Innovation an d management: international comparisons Author: Kuniyoshi Urabe,John Child,Tadao Kagono p.3)
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Bulk Deformation(old)
The bulk deformation process refine the starting shapes, sometimes improving mechanical properties, and always adding commercial value. Deformation process work by stressing the metal sufficently to cause it to plastically flow into the desired shape. Bulk deformation processes are performed as cold, warm, and hot working operations. Cold and warm working is appropriate when the shape change is less severe, and there is need a to improve mechanical properties and achieve good finish on the part. Hot working is generally required when massive deformation of large workparts is involved.
(Fundamentals of Modern Manufacturing, 3rd Edition; Mikell P. Groover ; Page: 390,391)
Bulk Deformation(new) [manufacturing method]
In deformation processes the workpiece shape is formed from solid metal or alloy by the displacement of material from unwanted locations into the positions required by the part shape. In Bulk deformation process the thickness of the workpiece is substantially changed and the imposed stresses are usually compressive, tensile stresses appear only as a result of inhomogeneous deformation. The technological concept of bulk workability has two components namely basic ductility of the material and the stress state induced by the process. Forging, extrusion, drawing, rolling etc are based on this concept.
(Technology of Metal Forming Processes Author: Surender Kumar p.8)
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Sintering(old)
Sintering is a heat treatment operation performed on the compact to bond its metallic particles, thereby increasing strength and hardness.The treatment is usually carried out at temperatures between 0.7 and 0.9 of the metal's melting point.
(P.Groover, Fundamentals of Modern Manufacturing third edition, page 349)
Sintering(new) [manufacturing method]
Packed powders will bond together when heated to temperatures in excess of approximately half of the absolute melting temperature. This phenomenon is termed sintering. A common characteristic of all forms of sintering is a reduction in surface area with concomitant compact strengthening. This occurs through the formation of interparticle bonds brought about by atomic motion at the sintering temperature. During liquid phase sintering a liquid phase coexists with a particulate solid at the sintering temperature. The liquid phase usually enhances the rate of interparticle bonding during sintering. Accompanying interparticle bonding are significant changes in the pore structure and compact properties including strenght, ductility, conductivity, magnetic permability and corrosion resistance.
(Liquid phase sintering Author: Randall M. German p.1)
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