Dense TRIP‐matrix composites containing 5 vol.% Mg‐PSZ as reinforcing phase were produced by employing the spark plasma sintering technique. A continuous and seamless interface between the ceramic particles and the steel matrix was achieved. Compression tests revealed better mechanical properties of the 5 vol.% Mg‐PSZ‐TRIP steel composites in comparison with both, pure and Al2O3 reinforced TRIP steel. The underlying deformation mechanism within the austenitic matrix entailed a pronounced martensite formation. An additional phase transformation was observed within the ZrO2 particles. The enhanced mechanical properties of the 5 vol.% Mg‐PSZ composite are dedicated to the transformation strengthening of the ceramic particles. Finally a model of the reinforcing mechanism is proposed.

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A composite consisting of 5 vol% MgO‐partially stabilized ZrO2 particles (Mg‐PSZ) and a TRIP‐steel‐matrix (CrNiMn steel; transformation induced plasticity) was produced through Spark Plasma Sintering. The processed material was tested under compression at various nominal strain rates (4 × 10−4 s−1; 10−3 s−1; 1 s−1, 102 s−1). Both, the pure steel and the composite showed a considerable plasticity and high strength due to the very fine grained steel matrix. The addition of 5 vol% ceramic particles led to a rise in the offset yield strength of 60 MPa till 90 MPa according to the applied strain rate. Up to a strain rate of 1 s−1, no change in offset yield strength was measured. A strain‐rate of 100 s−1 leads to a rise in the offset yield strength of approx. 100 MPa. Both, the ceramic and an increase in the strain rate implicate to an early generation of microdeterioration. Limited by the interfacial strength of steel and Mg‐PSZ, failure occurs early at the interfaces, which is shown in a decrease in the work hardening. During the compression, especially at higher strain‐rates, adiabatic heating occurred and counteracted to the martensitic transformation.

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