en گروه سرامیک Ceramic Materials and Engineering Research Paper Research Paper <span style="font-size:11pt"><span style="line-height:200%"><span style="font-family:Calibri,sans-serif"><span new="" roman="" style="font-family:" times="">This study deals with the dependence of mineral, microstructural, and textural properties on the duration of the indispensable yet easily controlled step of aging. For this purpose, a set of Cu/Zn/Al precursors were synthesized using a conventional constant‑pH method. The precipitates were aged for three different durations of zero, two, and four hours. The obtained precipitates, after several washing cycles and overnight drying, were then calcined at 623 K. Precursor and calcined samples were studied in terms of elemental composition, mineral composition, microstructure, texture, porosity, and metallic copper surface area. The results suggest that the dependence of precursor surface area on aging is realized by its dependence on phase composition. In the precipitate aged for two hours, the relative dominance of malachite leads to the highest pre‑calcination surface area of 57 m²/g. The individual thermal behaviors of the precursor phases and their pre‑calcination surface area values seem to conjointly determine the post‑calcination surface area of the samples. Such that a combination of ripened particle structure and susceptibility to calcination induced surface deterioration yields the lowest post‑calcination surface area after aging for four hours. The calcines derived from the unaged and the two‑hour‑aged precursors yield surface area values of approximately 57&ndash;58 m²/g, sensibly higher than that of the four‑hour‑aged sample. The Cu⁰ surface area values of the samples depend on aging duration through the effect it imparts on the Cu/Zn‑interdispersion of the precursor malachite phase. The highest Cu/Zn‑interdispersion is achieved in the two‑hour‑aged sample that finally exhibited a maximum Cu⁰ surface of 112 m²/g_Cu.</span><span lang="FA" dir="RTL" style="font-family:"Times New Roman",serif"></span></span></span></span><br> &nbsp; Cu/Zn/Al based Composite,Aging,Microstructure,Co precipitation,Hydrotalcite Malachite Transformation 0 0 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-1186-2&slc_lang=en&sid=1 Mohammad Hossein Ghayour Anarjan mhga.1278@gmail.com 1800319475328460022565 1800319475328460022565 No School of Metallurgy and Materials Engineering, Iran University of Science & Technology Maryam Mirasgari mirasgari.maryam@gmail.com 1800319475328460022566 1800319475328460022566 No Khwarizmi Technology Development Company Hajar Ghanbari hajar_ghanbari@iust.ac.ir 1800319475328460022567 1800319475328460022567 Yes School of Metallurgy and Materials Engineering, Iran University of Science & Technology Hossein Sarpoolaky hsarpoolaky@iust.ac.ir 1800319475328460022568 1800319475328460022568 No School of Metallurgy and Materials Engineering, Iran University of Science & Technology Amin Mardanloo mardanloo@khwarizmico.com 1800319475328460022569 1800319475328460022569 No Khwarizmi Technology Development Company