Oxidation kinetics of an AlCuFeCr approximant compound: an ellipsometric study

Wetting and adhesion properties of quasicrystals and complex metallic alloys

“…The second, low contact angle θ, is typical for naked alumina. It would not be different on oxidized aluminium nor is it on other types of Albased CMA that are submitted to high temperature annealing in air [28]. The first value is directly related to the contamination of the surface by organic molecules as a XPS scan easily teaches us.…”

A new orthorhombic approximant of the icosahedral Al–Cu–Fe quasicrystal

“…Annealing was intentionally performed in air, resulting in almost pure icosahedral phase particles (i-Al-Cu-Fe-B) covered by a thick (a few tens of nm) oxide layer [26,27]. The oxide layer acts as an efficient barrier in reducing the kinetics of Al diffusion from the Al matrix to the intermetallic particles.…”

Evolution of a Nanocrystalline (Co,Ni)Al2O4 Spinel Phase from Quasicrystalline Precursor

“…Although these materials were discovered over 25 years ago, yet considerable debate remains on the origins of their properties. The desirable properties reportedly include low friction, high hardness, high wear and corrosion resistance, and low surface energy 2–6 . The icosahedral and decagonal quasicrystals (DQCs) were found in Al–Cu–TM (TM=Fe, Ru, or Os) and Al–Co–TM (TM=Cu or Ni) 7,8 alloy systems.…”

“…The desirable properties reportedly include low friction, high hardness, high wear and corrosion resistance, and low surface energy. [2][3][4][5][6] The icosahedral and decagonal quasicrystals (DQCs) were found in Al-Cu-TM (TM 5 Fe, Ru, or Os) and Al-Co-TM (TM 5 Cu or Ni) 7,8 alloy systems. However, recent researches indicated that due to the large entropy of QCs, many of the discovered QCs prepared by conventional methods are only stable at higher temperatures while precipitation of a second phase or decomposition into crystalline phases occurs in these QCs at lower temperatures.…”