High temperature forming processes of alumina powder compacts were analyzed by using constitutive equations which are capable of predicting densification and grain growth under diffusional creep and power law creep. Experimental results for alumina powder compacts were compared with finite element calculations by using the constitutive equations. The effects of friction between alumina powder compact and punches during sinter forging of alumina powder compacts were also investigated. Densification mechanism maps of alumina powder, which can be used for the optimization of various process variables, were constructed under hot pressing and general states of stresses.

Issue Section:
Technical Papers
Topics:
Creep, Friction, Constitutive equations, Finite element analysis, Forging, High temperature, Hot pressing, Optimization, Sinter (Metallurgy), Stress
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