caa a22 4500 463226070 CHVBK 20180405153227.0 cr unu---uuuuu 170326e20070901xx s 000 0 eng 10.1007/s10853-007-1675-x doi (NATIONALLICENCE)springer-10.1007/s10853-007-1675-x Evolution of elastic mechanical properties during pressureless sintering of powder-processed metals and ceramics [Elektronische Daten] [Hugh Bruck, Yasser Shabana, Buli Xu, JonPaul Laskis] Metal and ceramic structures are being fabricated by pressureless sintering of compacted powders. As the powdered compacts are sintered, the pore volume fraction, generally referred to as porosity, decreases while the elastic mechanical properties increase. In this investigation, a new relationship is drawn between porosity and the evolution of elastic mechanical properties in pure ceramic and metal specimens. To develop this relationship, disk specimens are prepared from Nickel and Alumina powders, then sintered to different temperatures. The evolution of porosity is then evaluated from density measurements, while the corresponding elastic mechanical properties are measured using the ultrasonic wave propagation technique. These experimental measurements are compared with several different descriptions: (1) a conventional power law formula, (2) a quadratic formula, (3) a numerical micromechanical porosity simulation, and (4) a new empirical formula that combines the effects of evolving particle cohesion on the elastic properties of the matrix material and the reduction of these properties due to porosity. For the Young's modulus, the new empirical formula provides a better description than the alternative formulas. In the case of Poisson's ratio, similar conclusions could be made. However, the Poisson's ratio exhibited a different sensitivity to particle cohesion that was more directly related to the evolution of particle cohesion. Springer Science+Business Media, LLC, 2007 Bruck Hugh Department of Mechanical Engineering, University of Maryland, 20742, College Park, MD, USA aut Shabana Yasser Department of Mechanical Engineering, University of Maryland, 20742, College Park, MD, USA aut Xu Buli Department of Mechanical Engineering, University of South Carolina, 29208, Columbia, SC, USA aut Laskis JonPaul Department of Mechanical Engineering, University of South Carolina, 29208, Columbia, SC, USA aut Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/18(2007-09-01), 7708-7715 0022-2461 42:18<7708 2007 42 10853 https://doi.org/10.1007/s10853-007-1675-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10853-007-1675-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bruck Hugh Department of Mechanical Engineering, University of Maryland, 20742, College Park, MD, USA aut NATIONALLICENCE 700 1- Shabana Yasser Department of Mechanical Engineering, University of Maryland, 20742, College Park, MD, USA aut NATIONALLICENCE 700 1- Xu Buli Department of Mechanical Engineering, University of South Carolina, 29208, Columbia, SC, USA aut NATIONALLICENCE 700 1- Laskis JonPaul Department of Mechanical Engineering, University of South Carolina, 29208, Columbia, SC, USA aut NATIONALLICENCE 773 0- Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/18(2007-09-01), 7708-7715 0022-2461 42:18<7708 2007 42 10853 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer