A more general stationary solution of the diffusion equation

Information about the Position of the Coherent Spinodal Curve in the Al−Zn System by Means of the Course of the SAXS Intensity at Elevated Temperatures

“…where g" = a2g,18xin, /3 = 2~4 1 , E the scattering angle of the applied monochromatic rays of wavelength A, E the Young modulus, v the Poisson number, K the gradient energy term coefficient, q = (da/dxz,),o/a,, and a, the lattice constant of the homogeneous mixture. Moreover, the value of Tcohsp = T r h n x 323 "C for the A140.1 a t % Zn alloy agrees well with the experimental [4, 10, 111 as well as theoretical results [12] of other authors.…”

“…With the results presented in this paper one can be more sure that the position of Tcohsp is placed within the limits of the two calculated coherent spinodal curves [12,17] as shown in Fig. 2.…”

“…From these results it can be concluded that the information about the position of Teohsp gained by means of our method fits fairly well the data obtained by other authors. Furthermore, the results presented in [12] and [17] are additionally drawn (see the dashed and the dash-dotted line, respectively) as well as experimentally determined points taken from other authors (full circle [16], square [17], and empty circles [18 to 201). The meaning of the full triangle is explained in the inset of Fig.…”

Modulated structures and position of the coherent spinodal curve in Al–Zn(22 at%)–Cu(x) alloys

“…0, 0 A1-Zn(22 at%), a, A AlLZn(22 at%)-Cu(l ate/,) Discwssion of Kesults As shown by the XSAS and TEM results (see Fig. 3) the coherent spinodal curve shonld he situated in the A1-Zn(22 atyo)-Cu(O to 3 atyo) alloys a t (230 & 10) "C. This result agrees fairly well with the value of 228 "C obtained by Bartel and Rundman [15], who extrapolated their XSAS results of the A1-Zn(22 atyo) alloy to the boundary of the spinodal range and calculated a value of 210 "C using thermodynamical methods[19].…”

On the mode of decomposition of AlZn alloys

“…Of course, the position of the coherent spinodal shown in Pig. 1 is not as certain as that of the chemical spinodal, since the contributions of the coherency stresses to the free enthalpy are not so well known, but many authors [8,18,41, 421 agree in that the position of the coherent spinodal in the vicinity of the top of the miscibility gap should be situated about 30 K lower than that of the chemical one. I n our opinion, therefore, the results obtained by the quantitative and semi-quantitative methods are with a high probability situated close to the coherent spinodal.…”