Abstract
MnZn ferrites for power electronics require a well-controlled sintering window to balance high initial permeability (µ(i)) with low power loss (P(cv)). Here, an L9 (3(3)) orthogonal design was employed to quantify the main effects of sintering temperature, holding time, and oxygen partial pressure on µ(i) and P(cv) within the investigated processing window, enabling rapid mapping of feasible sintering windows. The orthogonal analysis identifies the relative significance of each factor and reveals a clear performance trade-off between µ(i) and P(cv). For maximising µ(i), the optimal sintering condition was 1250 °C, 4 h holding time, and 3.5% oxygen partial pressure, yielding a µ(i) of 3453 and a P(cv) of 466 mW/cm(3) at 100 kHz/200 mT. For minimising P(cv), the optimal condition was 1250 °C, 3.5 h holding time, and 5% oxygen partial pressure, resulting in a µ(i) of 2678, with P(cv) of 400 mW/cm(3) at 100 kHz/200 mT and 182 mW/cm(3) at 500 kHz/50 mT. Targeted verification together with XRD, SEM grain-size statistics, and magnetic-loss separation were used to strengthen the process-structure-property interpretation. Overall, the orthogonal-screening-plus-verification strategy provides a practical framework for predicting application-relevant performance trends of MnZn ferrites within a defined processing window.