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Stress intensifier

The main mechanical properties of importance are (9) maximum stress or stress intensify factor t7n,ax or cyclic stress or stress intensity range, Astress ratio R, cyclic loading frequency, cyclic load waveform (constant-amplitude loading), load interactions in variable-amplitude loading, state of stress, residual stress, crack... [Pg.61]

It is apparent from eqns S.N.6.1 that K is a convenient factor which scales the magnitudes of ail the stresses. It is for this reason that it is called the stress intensify fiictor. [Pg.232]

Geometry Di ontinuities as stress intensifiers Creation of galvanic potentials Chemical crevices Gravitational settling of solids Restricted geometry with heat transfer leading to concentration effects Orientation versus environment... [Pg.91]

Heat stress intensifies the effects of toxic chemical attacks on humans. This is explored in Section 37.6. [Pg.509]

Optical detectors can routinely measure only intensities (proportional to the square of the electric field), whether of optical pulses, CW beams or quasi-CW beams the latter signifying conditions where the pulse train has an interval between pulses which is much shorter than the response time of the detector. It is clear that experiments must be designed in such a way that pump-induced changes in the sample cause changes in the intensify of the probe pulse or beam. It may happen, for example, that the absorjDtion coefficient of the sample is affected by the pump pulse. In other words, due to the pump pulse the transparency of the sample becomes larger or smaller compared with the unperturbed sample. Let us stress that even when the optical density (OD) of the sample is large, let us say OD 1, and the pump-induced change is relatively weak, say 10 , it is the latter that carries positive infonnation. [Pg.3028]

Discontinuities intensify stresses. Since susceptibility to SCC commonly increases as stress level increases, stress-corrosion cracks may occur at a discontinuity, whereas smooth areas remain intact. [Pg.207]

The transverse orientation of the cracks along just one side of the tube reveals that bending provided the stresses for cracking. The tube sheet acted as a constraint to the bending, intensifying stresses in the tube wall adjacent to the sheet. [Pg.210]

Working in level A proteetion ean eause a variety of stresses. The equipment is heavy. The pressure to eomplete work tasks during a time frame is intensified beeause work time is limited by air supply. Heat stress ean be a problem, even in the winter. In the summer, the use of eooling vests ean keep you eool but also adds to the weight that you are earry-ing. Typieally, all level A workers have a sharp knife blade so that they ean eut themselves out of the suit if the air supply fails. Realizing that you may have to eut yourself out of this suit in ease of air supply failure adds more potential stress to the situation. [Pg.110]

As with alloys of other metals, nickel alloys may suffer stress-corrosion cracking in certain corrosive environments, although the number of alloy environment combinations in which nickel alloys have been reported to undergo cracking is relatively small. In addition, intergranular attack due to grain boundary precipitates may be intensified by tensile stress in the metal in certain environments and develop into cracking. Table 4.28 lists the major circumstances in which stress corrosion or stress-assisted corrosion of nickel and its alloys have been recorded in service and also shows the preventive and remedial measures that have been adopted, usually with success, in each case. [Pg.794]

As indicated earlier, protective oxide scales typically have a PBR greater than unity and are, therefore, less dense than the metal from which they have formed. As a result, the formation of protective oxides invariably results in a local volume increase, or a stress-free oxidation strain" . If lateral growth occurs, then compressive stresses can build up, and these are intensified at convex and reduced at concave interfaces by the radial displacement of the scale due to outward cation diffusion (Fig. 7.7) . [Pg.981]

Mechanical effects Corrosion can often be initiated or intensified by the conjoint action of mechanical factors. Typical examples include the presence of inherent or applied stresses, fatigue, fretting or cavitation effects. Inhibitors that are effective in the absence of some or all of these phenomena may not be so in their presence. In fact it may not always be possible to use inhibitors successfully in these situations and other methods of corrosion prevention will be required. [Pg.784]

Several findings support this model. For instance, an early report suggested that there is a positive correlation between the density of (postsynaptic) jS-adrenoceptors in rat cortex and behavioural resistance to a mild environmental stress (novelty and frustration) but a negative correlation between these parameters when the stress is intensified (Stanford and Salmon 1992). More recently, it has been proposed that the phasic response of neurons in the locus coeruleus (which governs attentiveness ) depends on their tonic activity (which determines arousal). Evidence suggests that the relationship between these two parameters is described by a bell-shaped curve and so an optimal phasic response is manifest only at intermediate levels of tonic activity (Rajkowski et al. 1998). [Pg.182]

Referring to Table 8.1, it is important to stress that a specific structural change may have an impact on more than just one process, and that it can also affect the total resulting impact of a change in opposite directions. As an example, turbulence in the water phase may increase the reaeration rate of the water phase increasing the emission rate of hydrogen sulfide and odorous substances thereby intensifies the negative effects of anaerobic conditions. [Pg.209]

Tensile stresses were intensified even under weak external compression, and a crisscross-like pattern was observed, suggesting a particular organization of the collagen fibrils. [Pg.357]


See other pages where Stress intensifier is mentioned: [Pg.397]    [Pg.418]    [Pg.397]    [Pg.420]    [Pg.421]    [Pg.420]    [Pg.421]    [Pg.18]    [Pg.188]    [Pg.381]    [Pg.408]    [Pg.130]    [Pg.397]    [Pg.418]    [Pg.397]    [Pg.420]    [Pg.421]    [Pg.420]    [Pg.421]    [Pg.18]    [Pg.188]    [Pg.381]    [Pg.408]    [Pg.130]    [Pg.90]    [Pg.208]    [Pg.470]    [Pg.228]    [Pg.180]    [Pg.783]    [Pg.104]    [Pg.156]    [Pg.141]    [Pg.6]    [Pg.442]    [Pg.156]    [Pg.224]    [Pg.766]    [Pg.7]    [Pg.43]    [Pg.14]    [Pg.419]    [Pg.69]    [Pg.194]    [Pg.243]   
See also in sourсe #XX -- [ Pg.420 , Pg.421 ]

See also in sourсe #XX -- [ Pg.420 , Pg.421 ]




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Intensifier

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