Drawing defects

Fracture of wires Fracture of metallic glasses Deformation texture Drawing defects Polycrystalline strengthening Fatigue of micro-wires Fatigue of metallic glasses Bonding wires... 

In order to prevent drawing defects due to over-hardened materials it is often useful... 

The theoretical approach consists in having a maximal leakage flux allowing the drawing of the defect edge clearly. 

As a rule, in practice, the surface defects are revealed by the magnetic-powder and capillary methods. However, in the case of nonmagnetic materials the magnetic-powder methods are not applicable and the capillary ones do not detect the subsurface defects or defects filled with the lubricant after the grinding, wire-drawing and so on. 

Defects in finished components can sometimes be traced as far back as casting problems in the ingot or billet from which the component was eventually produced. Defects in welded tubes may be linked to defective metal or to the welding process itself Defects in seamless tubes can originate in extrusion or drawing processes. 

Consider, for e.xample, a box of 100 transistors containing five defectives. Suppose tliat a transistor selected at random is to be classified as defective or non-defective. Let X denote die outcome, widi X = 0 associated with die drawing of a non-defective and X = 1 associated with die drawing of a defective. Then X is a discrete random variable with pdf specified by... 

Where f(x) is tlie probability of x successes in n performances. One can show that the expected value of the random variable X is np and its variance is npq. As a simple example of tlie binomial distribution, consider tlie probability distribution of tlie number of defectives in a sample of 5 items drawn with replacement from a lot of 1000 items, 50 of which are defective. Associate success with drawing a defective item from tlie lot. Tlien the result of each drawing can be classified success (defective item) or failure (non-defective item). The sample of items is drawn witli replacement (i.e., each item in tlie sample is relumed before tlie next is drawn from tlie lot tlierefore the probability of success remains constant at 0.05. Substituting in Eq. (20.5.2) tlie values n = 5, p = 0.05, and q = 0.95 yields... 

Platinum, palladium and the normal alloys of platinum used in industry are easily workable by the normal techniques of spinning, drawing, rolling, etc. To present a chemically clean surface of platinum and its alloys after fabrication, they may be pickled in hot concentrated hydrochloric acid to remove traces of iron and other contaminants —this is important for certain catalytic and high-temperature applications. In rolling or drawing thin sections of platinum, care must be taken to ensure that no dirt or other particles are worked into the metal, as these may later be chemically or elec-trolytically removed, leaving defects in the platinum. 

Design drawings Detail or fabrication drawings Materials requirements including composition, quality standards, and minimum structural properties Fabrication requirements and standards, including dimensional tolerances, allowable defects, and minimum structural properties Requirements for prototype and quality control tests and procedures Shipping and handling... 

These possible sources of problems in a molded part should be marked on the product drawing and explained to the mold designer for corrective action or creating an awareness of possible product defects. This is a necessary step in the chain of events in which the aim is to produce a tool that will provide useful products. Even if the mold s design, workmanship, and operation are carried out to the highest degree of quality, they cannot overcome a built-in weakness due to the product design. 

Draw one or more "plane-nets" for the "P" eation eombined with a "U" anion. Indicate all of the possible defects that can appear. Write the symbol of each as you proceed. Include pairs of defects as needed. 

Draw a heterogeneous lattice, using circles and squares to indicate atom positions in a simple cubic lattice. Indicate both Schottky and Frenkel defects, plus the simple lattice defects. Hint- use both cation and anion sub-lattices. 

For the spinel, Hercyanite, cissume that the cation changes in valence state. Then, draw a diagram illustrating the probable ion diffusion processes, give the diffusion conditions and the diffusion reactions, including the effect of induced crystal lattice defects. 

Optical elements, liquid crystalline materials in, 15 116—117 Optical emission spectra, 14 833-837 plutonium, 19 671—673 Optical emission spectroscopy (OES), archaeological materials, 5 742 Optical fiber(s), 13 391-392 24 618 defects in, 11 145 drawing of, 11 141-145 fabrication of, 11 135-141 health care applications for, 13 397 overcladding of, 11 144 remote measurements using, 14 234 in sensors, 22 270-271 sol-gel processing of, 11 144-145 strength of, 11 141-145 vitreous silica in, 22 444 Optical fiber sensors, 12 614-616 Optical germanium, 12 556... 

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