1 research outputs found
Fabrication and Thermoelectric Properties of n‑Type CoSb<sub>2.85</sub>Te<sub>0.15</sub> Using Selective Laser Melting
We
report a nonequilibrium fabrication method of n-type CoSb<sub>2.85</sub>Te<sub>0.15</sub> skutterudites using selective laser melting (SLM)
technology. A powder of CoSb<sub>2.85</sub>Te<sub>0.15</sub> was prepared
by self-propagating high-temperature synthesis (SHS) and served as
the raw material for the SLM process. The effect of SLM processing
parameters such as the laser power and scanning speed on the quality
of the forming CoSb<sub>2.85</sub>Te<sub>0.15</sub> thin layers was
systematically analyzed, and the optimal processing window for SLM
was determined. A brief postannealing at 450 °C for 4 h, following
the SLM process, has resulted in a phase-pure CoSb<sub>2.85</sub>Te<sub>0.15</sub> bulk material deposited on a Ti substrate. The Seebeck
coefficient of the annealed SLM prepared bulk material is close to
that of the sample prepared by the traditional sintering method, and
its maximum <i>ZT</i> value reached 0.56 at 823 K. Moreover,
a Ti–Co–Sb ternary compound transition layer of about
70 μm in thickness was found at a dense interface between CoSb<sub>2.85</sub>Te<sub>0.15</sub> and the Ti substrate. The contact resistivity
was measured as 37.1 μΩcm<sup>2</sup>. The results demonstrate
that SLM, coupled with postannealing, can be used for fabrication
of incongruently melting skutterudite compounds on heterogeneous substrates.
This lays an important foundation for the follow-up research utilizing
energy efficient SHS and SLM processes in rapid printing of thermoelectric
modules