Thermoelectric properties of Electro-Sinter Forged ZrNiSn

Among Half Heusler alloys, ZrNiSn exhibits promising thermoelectric properties, with the potential to achieve high values for the figure of merit, zT. However, the intrinsic thermal conductivity of ZrNiSn remains relatively high, hindering its overall thermoelectric performance. Here, we explore Electro-Sinter Forging as a novel technique for the production of ZrNiSn alloys. The thermal conductivity of the samples shows similar values to selective laser melted samples and as compared to spark plasma sintered samples, a reduction by ∼ 46 % on average is observed. Furthermore, the influence of the technique on the microstructure reveals the presence of intergranular channels of Sn:Zr which leads to an improvement in the electrical conductivity. Transport property measurements indicate that Electro-Sinter Forged ZrNiSn possesses a maximum figure of merit of 0.39 at 900 K. The work demonstrates the potential of Electro-Sinter Forging as an alternative sintering method for faster and more energy efficient manufacturing of thermoelectric materials.