ABSTRACT
Here dp is particle size and ζ is the coordination number that can be related to φ by the equation ζ 1.61(1 − φ)−1.48 (Nakagaki & Sunada 1968). The Rumpf equation relates the bulk stresses to the averaged forces over many contacts in the powder bed. The estimated average forces from bulk stresses are therefore free of the usually large noise in the forces directly measured between two individual particles, which is due to the strong dependence on local properties of the surfaces at contact. Parameters such as the Young modulus, hardness, asperity profile, etc., usually show high fluctuations across the particle surface (Micromaterials Co. 2005).
