A contribution to the Al-Pd-Cr phase diagram

作者：Kowalski W^*; Grushko B; Pavlyuchkov D; Surowiec M

来源：Journal of Alloys and Compounds, 2010, 496(1-2): 129-134.

DOI：10.1016/j.jallcom.2010.02.033

• Phase diagram
• Transition metals aluminides
• Electron diffraction

The Al-Pd-Cr alloy system was investigated in the compositional range above 50 at.% Al. The binary Al-Cr phases theta, eta, mu, nu and gamma(2) extend up to about 1, 2, 1, 1 and 3 at.% Pd, respectively. The binary Al-Pd epsilon, delta and beta-phases dissolve up to 3, 4 and at least 10 at.% Cr, respectively. Five ternary structures were revealed in a quite small compositional range adjusting to that of the Al-Cr p.-phase. One, resembling the high-temperature Al(3)Mn phase (T-phase, orth. a = 1.47, b = 1.24 and c = 1.25 nm), is formed in a small region around Al(77)Pd(7)Cr(16) composition. A hexagonal structure with a=1.77 and c = 1.25 nm resembling Al-Ni(Cu)-Cr zeta-phase was revealed around Al(81.5)Pd(1.5)Cr(17) and another hexagonal structure with very close lattice parameters around Al(73)Pd(11)Cr(16). A ternary epsilon-phase resembling that in Al-Ni-Cr (orth., a = 1.24, b = 3.46 and c = 2.04 nm) was found at 970 degrees C around the Al(77.5)Pd(1.5)Cr(21) composition. An additional orthorhombic phase with a=2.48, b=3.87 and c = 2.04 nm was found to be formed between about Al(80)Pd(4)Cr(16), Al(73)Pd(8)Cr(19), Al(77)Pd(4)Cr(19) and Al(77)Pd(6)Cr(17). Partial 930, 970, 990 and 1020 degrees C isothermal sections are presented.

• 出版日期2010-4-30