| Popis: |
To investigate the effects of solid solution alloying on thermoelectric properties of PbTe-based thermoelectric materials, 0.3 wt% Bi-doped (Pb/sub 1-x/Ge/sub x/)Te alloy powders (0/spl les/x/spl les/0.15) were fabricated by "melting/grinding" process, and hot-pressed at 650/spl deg/C and 750/spl deg/C for 1 hour in vacuum. At temperatures ranging from 25/spl deg/C to 450/spl deg/C, the (Pb/sub 1-x/Ge/sub x/)Te alloys exhibited more negative Seebeck coefficient, higher electrical resistivity and lower thermal conductivity with increasing GeTe content. The temperature, where the figure-of-merit of (Pb/sub 1-x/Ge/sub x/)Te reached a maximum, was lowered with increasing GeTe content x. When hot-pressed at 650/spl deg/C, 0.3 wt% Bi-doped PbTe and (Pb/sub 0.9/Ge/sub 0.1/)Te exhibited a maximum figure-of-merit of 1.07/spl times/10/sup -3//K at 400/spl deg/C and 1.25/spl times/10/sup -3//K at 300/spl deg/C, respectively. |
