Development of Lead-Free PTC Thermistor Materials

DOI DOI

Search this article

Description

The electric properties of bismuth- and sodium-modified barium titanate, Ba 1=x (Bi 1/2 Na 1/2 ), TiO 3 (BBNT) were studied as a lead-free PTC (positive temperature coefficient of resistivity) thermistor material usable over 130°C. Two semiconductorization processes and their electric properties are described. Lanthanum(La)-doped BBNT ceramics sintered in air still show dielectric behaviors, but Nb-doped ones have a low resistivity ? RT on the order of 103 ?cm at room temperature and show a PTC behaviors. Sintering under low O 2 atmosphere produces BBNT ceramics with less than 102 ?cm compared to those prepared in air. A trial PTC heater constructed using the BBNT semiconducting ceramics demonstrates a comparable performance of those made of the Pb-contained PTC ones. Our current research shows the BBNT ceramics with a switching temperature T s around 210°C by increasing the (Bi 1/2 Na 1/2 ) content x of the ceramics.

Journal

Details 詳細情報について

Report a problem

Back to top