Does anyone is working with conventional thermoelectric materials fabricated with the mechanical method of Hot Pressing (or Hot Press), the so called conventional materials as: Bi2Te3, PbTe, SiGe, AgSbTe2, etc.)
i need help on controlling the experiment of hot pressing, may be my reactor design: the material or the coating,
Does anyone have some experience on this ?
My sample either leaks out if I apply it enough pressure, or, it ends with porosity if I apply less pressure than the requiered for the Hot Pressing procedure.
Thank you for the help !
You need to optimize the temperature, pressure, and time as per your material. Also, the rate at which you are increasing/decreasing the current (i.e. the ramp rate) effects the process. Try to increase the current slowly like 50 A every 5 mins and follow the same while you are coming down. Hot-press the powder for atleast 20 mins to achieve high density.
You can go through the following research article, as it might help you build up some basic understanding behind achievement of nearly fully dense pellets using hot-pressing.
Thank you Nidhi !
As I write this I'm processing another sample, I hope to get some progress this time.
I was setting the temperature to 600 °C before, but now I reduced it to 580 °C to see if I got better results ,
Speaking about the time, I wait for 40 mins after reaching the the set up conditions and keep the sample pressed.
Regards !
At what temperature did you calcine your powder sample? Hot pressing should be done above that calcination temperature.
You should do the TGA analysis of your powder samples prior to the hot-pressing process, as it shows how your sample behaves with rising temperature and would help you choose an optimum temperature to hot press.
Good luck!
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