Methods for simulating macroscopic and microscopic behaviors in powder forming and sintering processes are presented.In the finite element method,the volume change in deforming material is taken into consideration by obeying the macroscopic constitutive equations allowing for the volume change.The microscopic rotation of powder particles during compaction is dealt with on the basis of the Cosserat continuum theory.In addition,a micro-macro method for simulating a sintering process of ceramic powder compacts based on the Monte Carlo and finite element methods is presented.The macroscopic non-uniform shrinkage during the sintering is calculated by the viscoplastic finite element method.In the microscopic approach using the Monte Carlo method,powder particles and pores among the particles are divided into many cells,and the growth of grains in the particles and the disappearance of pores are simulated by means of the Potts model.The microscopic and macroscopic approaches are coupled by exchanging microscopic and macroscopic results in each step.
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