Specimen annealing

The first observations on the development of periodic modulations were made on Pt surfaces annealed in vacuum in the temperature range 920 to 1300C[9J. The 1-dimensional grating structures were made by mechanically ruling portions of gratings on polycrystalline Pt specimens. Annealing caused extensive... 

The evidence that lamellae 15 nm thick can enter the hexagonal phase came from electron diffraction of specimens annealed as low as 236 °C at 0.54 GPa, 3 K lower than the maximum of the corresponding differential thermal analysis peak recorded for bulk polymer under the same conditions. At this annealing temperature lamellae were still entire, i.e. essentially of unaltered thickness although with some internal variation. No attempt was then made to anneal at lower temperatures and determine the orthorhombic/hexagonal transition temperature for this thickness. Such experiments offer, nevertheless, a direct approach by which the quantities of Eq. 9 may be determined. 

The compositions of the intermetallic compound layer grown and the adjacent phases were determined by EPMA on a few specimens annealed under different conditions. Point-to-point measurements, 10 to 25 on each specimen, across the intermetallic layer at a step of 3-10 pm showed its Ni (25.0 0.5 at.%) and Bi (75.0 0.5 at.%) contents to correspond to the stoichiometry of the NiBi3 intermetallic compound. 

Nevertheless, immiscibility and Al-Si ordering are minimized when specimens anneal at high temperatures for long periods and then are rapidly quenched. In natural and synthetic specimens that have experienced such cooling histories, the effects of cationic substitutions can be analyzed independent of other factors. For instance, a number of authors have examined transition temperatures from CUm to CT symmetry in completely disordered alkali feldspars (Nai- cK cAlSisOg), and the results (Fig. 26) indicate that the critical temperature decreases linearly with K content, since the larger K cation inhibits structural collapse (Kroll et al. 1980, 1986 Salje 1985, Harrison and Salje 1994... 

The hardness curve and diffraction patterns of Fig. 9-3 illustrate these changes for an alpha brass, a solid solution of zinc in copper, containing 30 percent zinc by weight. The hardness remains practically constant, for an annealing period of one hour, until a temperature of 200°C is exceeded, and then decreases rapidly with increasing temperature, as shown in (a). The diffraction pattern in (b) exhibits the broad diffuse Debye lines produced by the cold-rolled, unannealed alloy. These lines become somewhat narrower for specimens annealed at 100° and 200°C, and the Ka. doublet becomes partially resolved at 250°C. At 250°, therefore, the re-... 

Fig. 9-3 Changes in hardness and diffraction lines of 70 Cu-30 Zn specimens, reduced in thickness by 90 percent by cold rolling, and annealed for 1 hour at the temperatures indicated in (a), (b), (c), and (d) are portions of back-reflection pinhole patterns of specimens annealed at the temperatures stated (filtered copper radiation).

PfiT and npj for the melt-grown (a-m) and plasma activated sintered (arp) specimens annealed in the evaquated quartz at 793 K for 8.64x10 s. 

Microphotographs 27 and 28, Plate YIH, reveal the presence of the constituents a and E in cast specimens. Annealing these, as is easily seen, has not any considerable effect—a fact confirmed by mechanical tests (see Photographs 29-32 inclusive, Plates VIII-IX). 

Figure 5. Tan9-temperalure curves for the specimens annealed at 1S0 C lor 2h lor vapor-deposlied nylontt film, artd Au-MPPC and Cu-MPPC.

Samples annealed at 145°C showed an increase of Eoo relative to Eo and 45, giving Eo > Ego > 45 above 20°C and for specimens annealed at 158°C 90 > 0 > 45 above 40°C. The low value of 45 implied that a shearing process was taking place, and evidence favoured an inter-lamellar shear mechanism, which could occur presumably because of relaxation of intercrystalline tie molecules. 

The conformers of the ethylene glycoxy moeity of PET, have been studied in the amorphous and crystalline regions. The profiles of the 382 cm band and the 1020 cm band for a series of specimens annealed at different temperatures. Consistent results were obtained from both bands for the compositions of the three conformers, i.e., the trans conformer in the crystalline state and both the trans conformer and the gauche conformer in the amorphous state (365). 

Fig, 4. Constant compressive stress creep curves for composite specimens annealed at 1620 K for 4,50, and 75 h. 

Cation self-diffusion studies were carried out at 1200 to 1600C, under oxygen partial pressures of 2 x 10"5 to latm. The isotope Sr was used, with Gruzin s residual activity method. The bulk diffusion coefficients for specimens annealed in argon (P02 = 2 X 10" atm) could be represented by. 

The crystallization temperature peak of PLLA has been estimated at about 123°C, and therefore a proper temperature for annealing is around 100°C. At this thermal condition, crystal growth is faster than at lower temperature. This is illustrated in Figure 11.2, where the micro-structures of PLLA specimens annealed at 70 and 100°C at different treatment times are shown with polarized optical microphotography. It is clear that the density and size of spherulites increase with annealing time and temperature [23]. 

From a quantitative point of view, the Xc of quenched PLLA is generally around 3%, while PLLA annealed at 70 and 100°C can reach Xc of 23% and 56%, respectively [23]. The storage modulus, E, of PLLA, both quenched and annealed at 70° C, shows a sudden decrease around 60° C that is close to the Tg of 64°C. This is evidenced by an value that ranges between 5 and 10 MPa at 80°C. PLLA specimens annealed at 100°C maintain a much higher value of storage modulus above 60° C, with E around 1000 Pa at 80°C, due to the Xc contribution to the mechanical properties [23]. 

In order to determine the effect of sintering on mode I fracture toughness of the coating material, additional fracture toughness testing was carried out at ambient temperature using the test specimens annealed at 1316°C in air for 5, 20, 100, and 500 h. The sharp v-notches were introduced in the annealed specimens using the... 

Schafer et al. [15] have also investigated the reaction kinetics of an oxazoline functionalized butadiene-co-acrylonitrile copolymer with a poly(ethylene-co-methacrylic acid). A two-layer specimen was used for the kinetics study. FTIR spectroscopy was carried out on the two-layer specimen annealed at different temperatures from 170 to... 

Figure 1 Grain boundary microstructure in Fe-2.9at%Co polycrystalline specimen annealed at 1173K for 3h.

Figure 9.8 DSC thermograms for as-cast PSHQIO specimens annealed at 160°C for different periods as indicated on the plot, for which a fresh specimen was used for each run and the heating rate used was 20 °C/min. The inset gives a POM image of PSHQIO taken at 160 °C in the nematic region, showing Schheren texture. (Reprinted from Kim and Han, Macromolecules 26 3176. Copyright 1993, with permission from the American Chemical Society.)...

Figure 9.28 DSC thermograms for compression-molded 73/27 HBA/HNA copolyester specimens annealed at different temperatures ...

Figure 9.36 DSC thermograms for (a) as-cast PSHQIO specimens annealed at 130 °C for different periods, as indicated on the plot, and (b) as-cast PSHQIO specimens annealed at 130 °C for different periods, as indicated on the plot, having the following thermal histories an as-cast specimen was first annealed at 130 °C for 30 min, then heated to 190 °C in the isotropic region and held there for 30 min, and finally cooled down slowly to 130 °C for further annealing. A fresh specimen was used for each run and the heating rate was 20 C/min. (Reprinted from Han et al.. Molecular Crystals and Liquid Crystals 254 335. Copyright 1994, with permission from Taylor Francis Group.)...

Calibre 2061-15 Specimen Annealed 15 hrs 141°C before exposure, conditioned 40 hrs to ASTM D618A prior to testing, EtO sterilization grade... 

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