Stress accelerated

Stress-Accelerated Corrosion—increased corrosion rate caused by applied stresses. 

The behaviour of a wide range of a, a-0 and /3 brasses in various corrosive environments was studied by Voce and Bailey and the results summarised by Whitaker . Penetration by mercury and by molten solder was intercrystalline in all three types of brass. In moist ammoniacal atmospheres the penetration of unstressed brasses of all types was intercrystalline. Internal or applied stresses accelerated the intercrystalline penetration of a brasses and initiated some transcrystalline cracking, and also caused severe transcrystalline cracking of /3 alloys and transcrystalline cracking across the 0 regions in the two-phase brasses. Immersion in ammonia solution, however, caused intercrystalline cracking of stressed 0 brasses. 

Stress corrosion cracking (SCC) or embrittlement corrosion describes any of a number of corrosion processes where in a corrosive environment, localized stress accelerates the rate of corrosion that may occur under or within a deposit. 

Evaluation of Resiuts After the specimens have been reweighed, they should be examined carefully. Localized attack such as pits, crevice corrosion, stress-accelerated corrosion, cracking, or intergranular corrosion should be measured for depth and area affected. 

Environmental Cracking The problem of environmental cracking of metals and their alloys is very important. Of all the failure mechanism tests, the test for stress corrosion cracking (SCC) is the most illusive. Stress corrosion is the acceleration of the rate of corrosion damage by static stress. SCC, the limiting case, is the spontaneous cracking that may result from combined effects of stress and corrosion. It is important to differentiate clearly between stress corrosion cracking and stress accelerated corrosion. Stress corro-... 

There are various purposes of using a stirred vessel, and the required mixing effect depends on the purpose. For any mixing purpose, rapid and homogeneous dispersion is required. In a stirred vessel, forced convection by the rotation of an impeller occurs, that is, each element of the fluid has an individual velocity finally, turbulent flow based on the shear stress accelerates the mixing. Therefore, the shape of the impeller has a very important effect on the mixing state. However, there are various types of impeller shapes, and traditional impellers are classified into three types ... 

Mechanical stress accelerates the effect of environment on the adhesive joint. A great amount of data is not available on this phenomenon for specific adhesive systems because of the time and expense associated with stress-aging tests. However, it is known that moisture, as an environmental burden, markedly decreases the ability of an adhesive to bear prolonged stress, especially at slightly elevated temperatures. 

We note here that for simplicity, we have implied that "best performance" means highest system loss factor. This is the case for a number of damping applications, but not for all cases. D. J. Mead (12., L2.) has noted the quantitative importance of other system parameters (stiffness and mass) in optimizing a damping treatment in cases where maximum loss factor is not the criterion of best performance (e.g., minimizing stress, acceleration, etc.). These considerations are particularly important in controlling structural fatigue and equipment malfunction. 

O Donnell, B. White, J.R. Stress-accelerated photo-oxidation of polypropylene and glass fibre-reinforced polypropylene. Polym. Degrad. Stab. 1994, 44, 211-222. 

Stability—stress, accelerated, long-term storage, retest/expiry... 

Stability (stress, accelerated and long-term conditions)... 

Storage conditions, time points, tests Stress, accelerated and long-term... 

Although there have been conflicting reports, most chnicians believe that exposure to iron may contribute to the risk of bacterial infection since iron is used by microorganisms for metabolic functions. The association of IV iron with oxidative stress, acceleration of atherosclerosis, and other cardiovascular conditions has also been suggested. These potential long-term risks of IV iron therapy are not clearly defined and there are no data that unequivocally confirm that aggressive use of IV iron in CKD patients treated with erythropoietic therapy increases patient morbidity or mortality. ... 

Experiments on the stress-chemllumlnescence (SCL) behavior of TGDDM/DDS epoxy and nylon 66 specimens were performed under various conditions to determine the potential of the technique to measure stress-induced and stress-accelerated aging processes. Representative results of typical SCL experiments with epoxy specimens are shown In Figures 2 and 3 where emitted light (photon counts/s) Is plotted as a function of time and stress. In both... 

Stress chemiluminescence is concerned with measurement of the stress acceleration of on-golng chemiluminescent reactions such as thermooxldatlve aging occurring with or without mechanical deformation. 

In the case of thin film sintering the lateral constraint imposed by a rigid substrate allows a shrinkage only in the direction (z-direction) perpendicular to the film. The imposed constraint induces an in-plane tensile stress and the stress accelerates the shrinkage in the z-direction. From the lateral constraint Ex = Sy = 0, cr = 0, and cTx = cry = cr, and the expressions of the uniaxial strain rates in Eq. (5.33), the densification rate in the z-direction is expressed as... 

Doksum, K. and A. Hoyland (1992). Models for variable-stress accelerated life testing experiments based on wiener processes and the inverse gaussian distribution. Technometrics 34(1), 74- 2. 

Suppose that some units are snbjected to a constant stress accelerated life testing composed ofk stress levels. The testing units belong to old products with an initial period denoted Tq at nse condition, which are not perfect when they arrive at accelerated life testing. 

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