[T12] Ferrous Materials

[14F-T12-06] Numerical and Experimental Assessment of the Effect of Sintering Time and Temperature on Yielding Behaviour of Sintered Steel

*O. Schenk¹, A. Kaletsch¹, C. Broeckmann¹ (1.RWTH Aachen University, Germany)

キーワード：plasticity, Astaloy 85Mo, Rastagaev compression test, pore morphology, sintering

Powder metallurgical components reveal a high dimensional accuracy while offering a cost efficient and sustainable production. Since the inherent porosity affects the strength, the porosity is often reduced locally by sizing or cold rolling, thus increasing the strength. Although such processes require a profound understanding of plasticity, its dependency on porosity and the size and shape of individual pores is rarely reported. In this work, uniaxial compaction and dilatometry are used to produce cylindrical samples with different sintering states and densities. Microstructural analyses are performed to evaluate the effect of different sintering conditions on pore morphology and subsequently derive two-dimensional finite element models to virtually assess the effect of the pore morphology and density on plasticity. The results are compared with corresponding Rastagaev compression tests that are conducted with identical cylindrical samples. Additional three-dimensional simulations are performed based on μ-CT measurements to evaluate the difference between two- and three-dimensional models.