Cutting process

Extended defects range from well characterized dislocations to grain boundaries, interfaces, stacking faults, etch pits, D-defects, misfit dislocations (common in epitaxial growth), blisters induced by H or He implantation etc. Microscopic studies of such defects are very difficult, and crystal growers use years of experience and trial-and-error teclmiques to avoid or control them. Some extended defects can change in unpredictable ways upon heat treatments. Others become gettering centres for transition metals, a phenomenon which can be desirable or not, but is always difficult to control. Extended defects are sometimes cleverly used. For example, the smart-cut process relies on the controlled implantation of H followed by heat treatments to create blisters. This allows a thin layer of clean material to be lifted from a bulk wafer [261. 

Bruel M 1998 The history, physics, and applications of the smart-cut process MRS Bull. 23 35, 1998... 

The processing of components that are on the limits of technical feasibility is likely to result in out of tolerance variation. High forces and flow restriction in metalworking and metal cutting processes can lead to instability. Also, material flow in casting processes, where abnormal sections and complex geometries are present, can lead to variability problems and defects. 

In an older cutting process still much used, strands are formed into a bunch which is then cut by guillotine. 

Ion conducting glasses, 12 585-586 Ion-cut process, 14 448-449 Ion cyclotron (ICR) analyzers, 15 663-664 Ion cyclotron resonance instrument, 15 664 Ion-dipole interactions, 14 411-418 Ion doping, in photocatalysis, 19 94-95 Ion doses, measuring, 14 444—445 Ion engines, cesium application, 5 705 Ion exchange, 14 380-426... 

See also Ion beams Ion-cut process Ion implantation systems advantages and limitations of, 14 429 case hardening by, 16 208-209 channeling effect and, 14 435 in compound semiconductor processing, 22 185-188... 

We note from the phase diagram that some nickel remains dissolved in the diamond, but the amount is small, with mole fraction of carbon > 0.9998 at the eutectic temperature. Thus, diamond of reasonably high purity is obtained. At the present time, this and similar processes are used to produce large quantities of diamonds. The crystals are usually small and find most use in industrial grinding and cutting processes. 

Fresh-cut products differ from intact fruits and vegetables in terms of their physiology, handling and storage requirements. The fresh-cut process results in tissue and cell integrity disruption, with a concomitant... 

Calculations of collisions between molecules of a liquid have been made but the postulates on which they rest are not fully established. In fact it is not easy to define a collision between molecules of a liquid or between a solute molecule and a solvent molecule. In gases collision is pictured as a clean-cut process like the collision and rebound of two billiard balls, but in solution the solute molecule is always in contact with a solvent molecule and one might well consider a collision between them as a continuing or sticky collision. The frequency of collision and the mean free path are indefinite. We have no clear picture nor definition and it is not surprising that the mathematical formulas proposed are unsatisfactory. Collisions of one solute molecule with another solute molecule, however, seem to be capable of exact description, at least in some cases. 

Water is also used with oil and other additives in the form of an emulsion as a coolant and lubricant in cutting processes. These fluids must be nonflammable, as a spark from the cutting tool or electrical equipment would cause a fire, and they should not cause irritation to the skin or produce harmful vapours. Furthermore, for purposes of protection from corrosion, they should not cause corrosion of the cutting equipment or the material being cut and should give short-term protection from atmospheric corrosion. 

On receipt of the organic carcasses, all the documentation which arrives with the product must be checked. In particular the carcasses must have been stamped with their organic symbol, and have a reference number attached for traceability to continue through the primal cutting process. 

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