Sintered materials studied by small-angle neutron scattering

Sintered single-phase materials with open or dosed porosity are usually described by a two phase model. During sintering, the decrease of pore volume is accompanied with decreasing internal surface area measured by SANS. Such investigation can be extended to sintered WC-Co composites made from nano-crystalline powder having different kinds of internal surfaces. The deformation of remaining porosity after sintering can also be monitored by the 2D anisotropy of SANS distribution as the sintered body is processed through several steps of thermo-mechanical treatment. The macroscopic deformation of doped tungsten wire is followed by the elongation of the potassium gas filled bubbles and the annealing causes spheroidization with vanishing SANS anisotropy. The SANS method establishes a new description of mechanisms of thermomechanical processing. (C) 2000 Elsevier Science B.V. All rights reserved.