Temperature annealing

Among arsenic, bismuth, lead, antimony, and sulfur in the concentration range of 5—26 ppm, bismuth had the greatest unit effect (59). A decrease in the annealing temperature prior to cold deformation led to a decrease in the measured unit effectiveness, indicating that at low temperature bismuth is not in sohd solution. Lead lowered the recrystaUization temperature, provided that the samples were aimealed at 700°C or lower. A precipitation reaction between lead and sulfur was proposed (60). 

Annealing temperature rcj Vickers hardness Time at annealing temperature (minutes)... 

Estimate the time that it would take for recrystallisation to be completed at an annealing temperature of 700°C. Because the new strain-free grains grow by diffusion, you may assume that the rate of recrystallisation follows Arrhenius law, i.e. the time for recrystal-lisation, f is given by f, =... 

Figure 6 Backscattering spectra for a thin fiim of Ni deposited on an amorphous SiOj fiim grown on top of Si (111) for three different annealing temperatures.

Two common types of membrane materials used are cellulose acetate and aromatic polyamide membranes. Cellulose acetate membrane performance is particularly susceptible to annealing temperature, with lower flux and higher rejection rates at higher temperatures. Such membranes are prone to hydrolysis at extreme pH, are subject to compaction at operating pressures, and are sensitive to free chlorine above 1.0 ppm. These membranes generally have a useful life of 2 to 3 years. Aromatic polyamide membranes are prone to compaction. These fibers are more resistant to hydrolysis than are cellulose acetate membranes. 

In a detailed study the dissolution kinetics of shock-modified rutile in hydrofluoric acid were carefully studied by Casey and co-workers [88C01], Based on the defect studies of the previous sections in which quantitative measures of point and line defects were obtained, dissolution rates were measured on the as-shocked as well as on shocked and subsequently annealed powders. At each of the annealing temperatures of 200, 245, 330, 475, 675, 850, and 1000 °C, the defects were characterized. It was observed that the dissolution rates varied by only a factor of 2 in the most extreme case. Such a small effect was surprising given the very large dislocation densities in the samples. It was concluded that the dissolution rates were not controlled by the dislocations as had been previously proposed. 

Annealing temperature (°C) Density of the amorphous material (da) (g/cm ) Amorphous orientation function (fa) Crystallite length (Ic) (nm) Long period (L) (nm) Degree of crystallinity (X ) Substructure parameter (A) Axial elastic modulus ... 

Annealing temperature rc) Annealing time (min) Birefringence (An) Anid Volume crystallinity (%) TTM fraction Critical dissolve time (s) Amorphous orientation function (/ )... 

The most desirable annealing temperatures for amorphous plastics, certain blends, and block copolymers is just above their glass transition temperature (Tg) where the relaxation of stress and orientation is the most rapid. However, the required temperatures may cause excessive distortion and warping. 

Poly(arylene ether ketone) and poly(arylene ether sulfone) were also tried to be incorporated into the hybrids with silica gel by means of the sol-gel procedure [19, 20], For example, triethoxysilyl-terminated organic polymer was subjected to co-hydrolysis with tetraethoxysilane. A systematic change in mechanical and physical properties of the hybrid glass has been found with the content of organic polymer and the annealing temperatures. 

Table 2. Lamellar thickness 1, as function of annealing temperature at 5.3 Kbar for PE cold-drawn to a natural draw ratio X 8.

Fig. 5. Size and density of Ni nanocrystals as a function of (a) initial Ni film thickness and (b) annealing temperature (inset shows the AFM micrograph of Oswalt ripening at high temperatures).

For similar samples on alumina, these effects are not observed, as Indicated In Table I. Mo migration of aluminum or oxygen species Is observed In AES, and the capacity of the film to adsorb carbon monoxide Is not altered by changing the annealing temperature from 525 to 760 K. 

Flame cracks are easily removed by warming the glass, gently at first to avoid spreading the crack, and raising it to the annealing temperature. When joints are in the vicinity care must be taken to heat everything uniformly and to anneal as a whole. 

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