Journal of Crystal Growth, Vol.282, No.1-2, 228-235, 2005
Extended investigation of porosity in quasicrystals by synchrotron X-ray phase contrast radiography: Part II, in grains of other alloys and structures than AlPdMn
The systematic study, by synchrotron X-ray phase sensitive radiography of the porosity in the bulk samples of the icosahedral Al-Pd-Mn quasicrystal (i-Al-Pd Mn) reported in the Part I of an emended investigation of porosity in quasicrystals (Part 1) has shown that the origin of this porosity is difficult to identify, As it is not clear if this type of porosity is characteristic of icosahedral quasicrystals in the present work. which is the Part II of the same investigation. we have studied the porosity in single grains of various alloys and structures (i-Al Pd Re, i-Zn Mg-Rare-Earth. d-Al-Co-Ni. xi'-Al-Pd-Mn) in order to attempt to elucidate this question. The results show that the presence of facetted micrometric pores is not restricted to icosahedral quasicrystals. Otherwise the part played by these pores to their actual existence and stability remains as questionable. The samples contain pores or not independently of the growth method, which does not seem to have an influence on the pores. Since pores were only observed in samples of the Al-rich phases this element could be an important ingredient for the formation of pores during the solidification process as it has been suggested in Part I. (c) 2005 Elsevier B.V. All rights reserved.