Quasiperiodic phases with symmetries forbidden by classic crystallography have been observed in systems of aluminum with transition metals. The paper presents investigations of the Al-Ni-Cr and Al-Pd-Cr phase diagrams by scanning and transmission electron microscopy, differential thermal analysis and X-ray powder diffractometry. In the Al-Ni-Cr four ternary crystalline phases were formed close to the compositions of binary m-Al₄Cr and h- Al₅Cr. One of them, designated as z with hexagonal structure, was formed in a wide range of composition between Al₈₂Ni₂Cr₁₆ and Al₇₁Ni₁₁Cr₁₈. The second phase z₁, was found in samples containing slightly more aluminum. Electron diffraction patterns shows that the c parameter was the same as in z, but the a parameter was √3 larger. Another phase, designated as f, was found around Al₇₉Ni₉Cr₁₂. It exhibits a monoclinic structure and it incongruently melts at 835°C. The fourth ternary phase was found in Al₇₆Ni₂Cr₂₂ alloy annealed at 1000°C. We designate it as e. It was found to be only stable at elevated temperatures and not observed in the same sample at 900°C. The structure of the e phase was found to be orthorombic.

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