抄録
Nuclear magnetic resonance (NMR) is powerful tool for characterizing porosity and its evolution during consolidation and sintering.The open porosity is filled with NMR sensitive liquids or gases and signal intensity and relaxation times are used as probes of the porosity. Gas phase imaging allows non-destructive characterization of density, and spatially resolved measurements of pore size, surface area, and adsorption isotherms. Images obtained as a function of pressure provide a map of adsorption isotherms that compare well to results obtained using conventional N2 BET adsorption. Measurements on samples with a range of densities and on samples fabricated with deliberate density gradients demonstrate a variety of pore characterization measurements and the utility of the NMR technique for assessing microstructural homogeneity and for following changes as sintering occurs. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-ACO4-94AL85000.
