Dimensional precision

TSs has experienced an extremely low total growth rate, whereas TPs have expanded at an unbelievably high rate. Regardless of the present situation, CM and TM are still important, particularly in the production of certain low-cost products as well as heat-resistant and dimensionally precise products. CM and TM are classified as high-pressure processes, requiring 13.8-69 MPa (2,000 to 10,000 psi) molding pressures. Some TSs, however, require only lower pressures of down to 345 kPa (50 psi) or even just contact (zero pressure). 

The foundry technology does not admit the manufacture of dimensionally precise products of complex shapes. For this reason, sintered basalt technology has been developed for the manufacture of nozzles, drawing dies, dies for auger brick machines, etc., where the materials exhibit a resistance to abrasion still higher than that of cast basalt. The fused basalt powder is mixed with a plasticiser and pressed the pressings are sintered in an electric tunnel kiln at 1120 to 1140 C. 

Highly mechanized plants can produce up to 300 unsintered articles/min/press. The achievable dimensional precision of the molded article is very high with tolerances down to several tens of microns in thickness and ca. 1 % in weight. Greater tolerances are allowable for large format refractory products. 

Throughput of dry presses is high. Dimensional precision of the greenware (unfired molded article) is good... 

Anode. Metal electrodes of high dimensional precision are essential for maintaining a uniform distance between the electrode and a membrane of large size, and an electrode distance as small as possible in the membrane cell. It is preferable to locate the membrane near the anode, to minimize the thickness of the boundary layer at the membrane during electrolysis. 

At the beginning of industrialization, various designs of mechanical punch-and-die presses with single or multiple cavities, including stone presses with indexed die tables, were used, particularly for the manufacture of high-quality bricks that required dimensional precision for their application (e.g., refractory bricks). Among the earliest machines of this type was the Couffmhal press (Fig. 6.10-14, Section 6.10.2). Later, hydraulic presses were also used. 

Well-defined inorganic crystalline structures yielding a large variety of structural types differing in the channel diameters, geometry, and dimensionality. Precisely defined inner void volume providing high-surface areas up to 600 m"/g. 

Davim JP, Reis P (2005) Damage and dimensional precision on milling carbon fiber-reinforced plastics using design experiments. J Mater Proc Technol 160(2) 160-167... 

Microfiuidic systems manipulate or process tiny 10 to 101 volumes of fluids in channels with dimensions of tens to hundreds of micrometers. These systems, built using various microfabrication techniques, offer a number of advantages for chemical and biological analysis compared to standard laboratory instrumentation including low consumption of samples and reagents, low cost for mass production, short times for analysis, fiexibility and dimensional precision, and separations and detections with high resolution and sensitivity. They can also probe physical phenomena and mechanisms that... 

Injection molding Three-dimensional precise shape... 

Nanoscale devices are also being fabricated with the objective of electronically observing biological systems in their natural environments, with dimensional precision of a nanometer size range. Since the diameter of a DNA molecule is approximately 2 nm, nanoscale devices offer the prospect for manipulating or monitoring biological molecules. 

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