Role of stabilisers in the design of Ti aqueous suspensions for pressure slip casting

Autor: C. Pagnoux, Antonio Javier Sanchez-Herencia, R.G. Neves, Begoña Ferrari, Elena Gordo
Přispěvatelé: Universidad Carlos III de Madrid [Madrid] (UC3M), Institute of Ceramics and Glass, Axe 1 : procédés céramiques (SPCTS-AXE1), Science des Procédés Céramiques et de Traitements de Surface (SPCTS), Université de Limoges (UNILIM)-Ecole Nationale Supérieure de Céramique Industrielle (ENSCI)-Institut des Procédés Appliqués aux Matériaux (IPAM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Ecole Nationale Supérieure de Céramique Industrielle (ENSCI)-Institut des Procédés Appliqués aux Matériaux (IPAM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Rok vydání: 2014
Předmět:
Zdroj: Powder Technology
Powder Technology, Elsevier, 2014, 263, pp.81-88. ⟨10.1016/j.powtec.2014.04.093⟩
e-Archivo. Repositorio Institucional de la Universidad Carlos III de Madrid
instname
ISSN: 0032-5910
DOI: 10.1016/j.powtec.2014.04.093
Popis: Colloidal processing has long been used in ceramics to achieve green bodies with high densities, complex shapes and homogeneous microstructures, but they are rarely used to shape metal powders because of their high density and high surface reactivity. However, the possibility of processing fine particles makes these techniques interesting for metals, such as titanium, with a low density and high melting point. This work presents encouraging results in the design of aqueous suspensions of Ti particles to be shaped into bulk pieces by pressure slip casting (PSC), which opens new paths for the processing of fine and complex microstructures. Ti powders, measuring 10 μm in size, and mixtures of Ti and Al₂O₃ powders (added up to 5 wt.%) were dispersed in water by the addition of different stabilisers. The influence of the stabilisers in the slurry behaviour (in terms of nature, stereochemistry and active functional groups) was determined, as well as the incorporation of ceramic particles. A polyacrylic-based dispersant was selected as the best stabiliser to incorporate a second component (Al₂O₃) into the Ti suspension, whereas shear-thinning additives, such as TIRON, are preferred for PSC shaping. Suspensions with 1 wt.% Al₂O₃ were selected for processing composites by PSC and sintering. Sintered materials were characterised by measuring the density, oxygen content, hardness and microstructure analysis by SEM. Ti bulk pieces with 97% density and fine and homogeneous microstructure, of which the relationship between the oxygen content and hardness agrees with that measured for CPTi grade 4 (249 ± 24 HV30), can be processed by PSC. The authors would like to acknowledge the financial support from the Spanish Government through the projects MAT 2009-14448-C02-01 and 02, MAT2012 38650-C02-01 and 02 and to the regional government of Madrid through the programme Estrumat (Ref. S2009/MAT-1585).
Databáze: OpenAIRE
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