Effects of BN Dopant on Electrical Characteristics of Barium-Excessive BaTiO3 Ceramics for Laminated Positive Temperature Coefficient Thermistors Fabricated by Tape Casting Technique

2011 ◽  
Vol 415-417 ◽  
pp. 994-999
Author(s):  
Bin Bin Chen ◽  
Shu Ping Gong ◽  
Jian Qiao Liu ◽  
Lian Hua Li ◽  
Dong Xiang Zhou
Keyword(s):  
Charge Carrier ◽  
Temperature Coefficient ◽  
Tape Casting ◽  
Positive Temperature Coefficient ◽  
State Density ◽  
Room Temperature Resistivity ◽  
Positive Temperature ◽  
Charge Carrier Density ◽  
Acceptor State ◽  
Casting Technique

The barium-excessive BaTiO3 ceramics with BN addition for laminated positive temperature coefficient (PTC)thermistors are fabricated. The tape casting technique and reduction/reoxidation process are employed into the fabricating procedure. The influences of BN additive on ceramic characteristics are discussed. The addition over 5% leads to rectangular and abnormal large grains. The 5% BN-doped ceramics shows a resistivity of 233 Ω•cm and PTC jump of 3.4 orders of magnitude. The charge carrier density in grain bulk and acceptor state density at grain boundaries are evaluated. The correlation of BN doping amount with room temperature resistivity, PTC jump, reoxidation effect as well as charge carrier and acceptor state density are investigated.

Positive temperature coefficient of resistivity effect in Pb-doped KnbO3

2002 ◽  
Vol 17 (12) ◽  
pp. 2989-2992 ◽  
Author(s):  
Irena Pribošič ◽  
Darko Makovec ◽  
Miha Drofenik
Keyword(s):  
Phase Transition ◽  
Temperature Coefficient ◽  
Ferroelectric Material ◽  
Positive Temperature Coefficient ◽  
Cubic Phase ◽  
Room Temperature Resistivity ◽  
Positive Temperature ◽  
Ptcr Effect ◽  
Temperature Coefficient Of Resistivity ◽  
Temperature Resistivity

KnbO3 is a ferroelectric material with a Curie temperature (TC) at 415°C, thus giving it the potential to be a material for high-temperature positive temperature coefficient of resistivity (PTCR) applications. In this study, we investigated the PTCR effect in donor-doped KnbO3 ceramics containing 0, 0.1, 0.2, and 0.3 mol% PbO. The donor-doped KnbO3 ceramics exhibited a PTCR anomaly with a relatively low room-temperature resistivity. The temperature of the tetragonal-to-cubic phase transition (TC) of the KnbO3 decreased with the amount of added PbO, while the orthorhombic-to-tetragonal phase transition (TOT) remained unchanged.

Fabrication of Lead-Free and High Tc Positive Temperature Coefficient of Resistivity Ceramics Sintered in Air

2011 ◽  
Vol 415-417 ◽  
pp. 1005-1008
Author(s):  
Jun Zhao ◽  
Hai Bo Yang ◽  
Shu Ping Gong ◽  
Dong Xiang Zhou
Keyword(s):  
Temperature Coefficient ◽  
Solid State Reaction Method ◽  
Positive Temperature Coefficient ◽  
Lead Free ◽  
Room Temperature Resistivity ◽  
Positive Temperature ◽  
Conventional Solid State Reaction ◽  
High Tc ◽  
C Value ◽  
Temperature Coefficient Of Resistivity

As a lead-free positive temperature coefficient of resistivity (PTCR) material, [Ba0.95-x (K0.5Bi0.5)0.05Cax]1-yNbyO3 system was prepared by the conventional solid-state reaction method. All samples sintered in air at 1300°C possess PTC characteristics as well as semi-conductivity characteristics, especially they show high Tc(130°C~160°C) value and the jump of the resistivity (maximum resistivity ρmax / minimum resistivity ρmin ) is four orders of magnitude. Samples with the composition of 0.3mol% Nb5+ have low room-temperature resistivity (ρ25°C) of ~103Ω.cm.

Positive Temperature Coefficient Behavior of the Graphite Nanofibre and Carbon Black Filled High-Density Polyethylene Hybrid Composites

2008 ◽  
Vol 47-50 ◽  
pp. 226-229 ◽  
Author(s):  
Qi Li ◽  
Jong Wan Kim ◽  
Tae Hee Shim ◽  
Yun Ki Jang ◽  
Joong Hee Lee
Keyword(s):  
Carbon Black ◽  
Temperature Coefficient ◽  
High Density Polyethylene ◽  
Hybrid Composites ◽  
Positive Temperature Coefficient ◽  
High Density ◽  
Hybrid Nanocomposites ◽  
Room Temperature Resistivity ◽  
Positive Temperature ◽  
Temperature Resistivity

The graphite nanofiber (GNF) and carbon black filled high-density polyethylene (HDPE) hybrid nanocomposites were prepared by solution mixing and melt blending techniques. The effect of addition of GNF on the positive temperature coefficient (PTC) behavior of the nanocomposites was investigated. The incorporation of small amount of GNF into HDPE/CB composites showed a significant improvement in PTC intensity and repeatability of the hybrid nanocomposites. The maximum PTC intensity was observed for the HDPE/CB/GNF (80/20/0.25) nanocomposite with a relatively low room temperature resistivity.

Swelling and electrical properties of LLDPE reinforced by SWCNTs nanocomposites for radiation and sensors applications

2019 ◽  
pp. 089270571987920
Author(s):  
AM Abd Elbary ◽  
MT Tammam ◽  
NI Aljuraide
Keyword(s):  
Electrical Properties ◽  
Temperature Coefficient ◽  
Irradiation Dose ◽  
Negative Temperature ◽  
Positive Temperature Coefficient ◽  
Positive Temperature ◽  
Γ Irradiation ◽  
Weight Percentage ◽  
Casting Technique ◽  
Walled Carbon Nanotubes

Linear low-density polyethylene (LLDPE) incorporated with single-walled carbon nanotubes (SWCNTs) by mistreatment casting technique. The result of various weight percentage loadings of SWCNTs on the swelling and electrical properties of LLDPE/SWCNTs nanocomposite also γ-irradiation effects had been investigated. It was found that, at low concentration, it uniformly disperses into an LLDPE matrix and provides LLDPE/SWCNTs nanocomposites with abundant improved electrical properties by nine orders of magnitude. Positive temperature coefficient of conductivity (PTCC)/negative temperature coefficient of conductivity (NTCC) was affected by the SWCNT contents. Transmission electron microscopy and scanning electron microscope techniques were used to investigate the dispersion of SWCNTs in the LLDPE matrix. Linear exceptional modification within direct current electrical conduction of percolative threshold-loaded LLDPE as a perform of γ-irradiation dose will be used as a nontoxic, easy, inexpensive, and sensitive method to evaluate the irradiation dose in range 10 Gy–1 kGy also can be used in fabrication of firing sensors with various ranges of temperatures.

scholarly journals Effects of Manganese on Highly Donor-Doped Barium Titanate Ceramics with Resistivity of Positive Temperature Coefficient

2020 ◽  
Vol 26 (4) ◽  
pp. 457-462
Author(s):  
Jianqiao LIU ◽  
Guohua JIN ◽  
Yuzhen CHEN ◽  
Zhaoxia ZHAI
Keyword(s):  
Electrical Properties ◽  
Temperature Coefficient ◽  
Positive Temperature Coefficient ◽  
Room Temperature Resistivity ◽  
Positive Temperature ◽  
Layer Width ◽  
Average Grain Size ◽  
Donor And Acceptor ◽  
Aerial Oxidation ◽  
Titanate Ceramics

Highly donor-doped ceramics with composition of Ba0.984Y0.016TiO3 were prepared for thermistors with positive temperature coefficient of resistivity (PTCR) via a route of solid reaction, reducing sintering and aerial oxidation. The effects of Mn additive were investigated on the ceramic characteristics of composition, morphology and electrical properties. The Mn incorporation affected little on ceramic composition but resulted in an obvious change in ceramic morphology, which illustrated the average grain size of 1.16, 1.65 and 1.01 μm for Mn addition amount of 0, 0.0005 and 0.0010, respectively. The grain growth, together with the Mn additive, influenced the electrical properties of room temperature resistivity, PTCR jump, donor and acceptor densities as well as the depletion layer width.

Sign in / Sign up

Export Citation Format

Share Document