Netshape manufacturing of CuCr medium voltage circuit breakers

Continuum mechanics based modelling and finite element based simulation methods are commonly proved to represent cost efficient and timesaving tools for optimization of filling body geometries and tool designs. In case of adequate material descriptions they also allow to reduce the risk of flaws such as formation of cracks and low-density areas, respectively. By linking the simulation tools for compaction and sintering further enhancements are achievable such as minimized sintering distortions this way forming the basis for an advanced design tool of netshape (NS) manufacturing routes. The technical applicability and economic relevance of the proposed approach is demonstrated on the example of NS manufactured CuCr contacts for medium voltage circuit breakers as they are used in electric power distribution. The approach comprises modelling of powder compaction and sintering in an integrative manner via Drucker-Prager/Cap plasticity modelling and non-linear visco-elastic transversally isotropic sintering modelling, respectively. In particular, the careful calibration procedure for the material models used for the compaction and sintering regime with respect to the experimental findings of several types of mechanical green body tests as well as sintering experiments is described in detail. This way the presented approach claims and focusses on the first-in-class show case of a CuCr circuit breaker component being netshape manufactured.