scholarly journals Sintering densification curve: A practical approach for its construction from dilatometric shrinkage data

2008 ◽  
Vol 40 (2) ◽  
pp. 117-122 ◽  
Author(s):  
K. Maca ◽  
V. Pouchly ◽  
A.R. Boccaccini
Keyword(s):  
High Temperature ◽  
Sintering Temperature ◽  
Practical Method ◽  
Practical Approach ◽  
Powder Technology ◽  
Ceramic Processing ◽  
Sintering Process ◽  
Densification Curve ◽  
Sample Density ◽  
Sintering Shrinkage

This article summarizes the usage of high-temperature dilatometry in ceramic processing and powder technology with special attention on the description of the sintering process. A practical method for transformation of dilatometric shrinkage data into densification curves (the dependence of the sample density on sintering temperature or time) is described in detail. A new automatic procedure to recalculate sintering shrinkage data allowing the plot of the densification curve has been developed, which is presented here.

scholarly journals Pressureless Sintering of YIG Ceramics from Coprecipitated Nanopowders

2021 ◽  
Vol 7 (5) ◽  
pp. 56
Author(s):  
Yimin Yang ◽  
Xiaoying Li ◽  
Ziyu Liu ◽  
Dianjun Hu ◽  
Xin Liu ◽  
...  
Keyword(s):  
High Temperature ◽  
Calcination Temperature ◽  
Sintering Temperature ◽  
Raw Materials ◽  
Secondary Phase ◽  
Coprecipitation Method ◽  
Pressureless Sintering ◽  
Densification Behavior ◽  
Sintering Process

Nanoparticles prepared by the coprecipitation method were used as raw materials to fabricate Y3Fe5O12 (YIG) ceramics by air pressureless sintering. The synthesized YIG precursor was calcinated at 900–1100 °C for 4 h in air. The influences of the calcination temperature on the phase and morphology of the nanopowders were investigated in detail. The powders calcined at 1000–1100 °C retained the pure YIG phase. YIG ceramics were fabricated by sintering at 1200–1400 °C for 10 h, and its densification behavior was studied. YIG ceramics prepared by air sintering at 1250 °C from powders calcinated at 1000 °C have the highest in-line transmittance in the range of 1000-3000 nm. When the sintering temperature exceeds 1300 °C, the secondary phase appears in the YIG ceramics, which may be due to the loss of oxygen during the high-temperature sintering process, resulting in the conversion of Fe3+ into Fe2+.

scholarly journals Master sintering curve: A practical approach to its construction

2010 ◽  
Vol 42 (1) ◽  
pp. 25-32 ◽  
Author(s):  
V. Pouchly ◽  
K. Maca
Keyword(s):  
Activation Energy ◽  
Practical Method ◽  
Practical Approach ◽  
Particle Sizes ◽  
Sintering Process ◽  
Cubic Zirconia

The concept of a Master Sintering Curve (MSC) is a strong tool for optimizing the sintering process. However, constructing the MSC from sintering data involves complicated and time-consuming calculations. A practical method for the construction of a MSC is presented in the paper. With the help of a few dilatometric sintering experiments the newly developed software calculates the MSC and finds the optimal activation energy of a given material. The software, which also enables sintering prediction, was verified by sintering tetragonal and cubic zirconia, and alumina of two different particle sizes.

scholarly journals Current understanding and applications of the cold sintering process

2019 ◽  
Vol 13 (4) ◽  
pp. 654-664 ◽  
Author(s):  
Tong Yu ◽  
Jiang Cheng ◽  
Lu Li ◽  
Benshuang Sun ◽  
Xujin Bao ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Sintering Temperature ◽  
Applied Pressure ◽  
Processing Technique ◽  
Rechargeable Batteries ◽  
Processing Conditions ◽  
Ceramic Processing ◽  
Sintering Process ◽  
Novel Processing ◽  
Processing Techniques

Abstract In traditional ceramic processing techniques, high sintering temperature is necessary to achieve fully dense microstructures. But it can cause various problems including warpage, overfiring, element evaporation, and polymorphic transformation. To overcome these drawbacks, a novel processing technique called “cold sintering process (CSP)” has been explored by Randall et al. CSP enables densification of ceramics at ultra-low temperature (⩽300°C) with the assistance of transient aqueous solution and applied pressure. In CSP, the processing conditions including aqueous solution, pressure, temperature, and sintering duration play critical roles in the densification and properties of ceramics, which will be reviewed. The review will also include the applications of CSP in solid-state rechargeable batteries. Finally, the perspectives about CSP is proposed.

scholarly journals Synthesis and Structural Investigations of Ag-Added Ba-CuO Mixed Oxide for Gas Sensing

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Ahmed Mohamed El-Sayed ◽  
Fathy Mohamed Ismail ◽  
Saad Mabrouk Yakout
Keyword(s):  
Solid State ◽  
Gas Sensing ◽  
Sintering Temperature ◽  
Structure Characterization ◽  
Ceramic Processing ◽  
Sintering Process ◽  
Structural Investigations ◽  
X Ray ◽  
State Ceramic ◽  
Infrared Absorption Spectra

Compositions having the general formula BaTiO3- wt% Ag, where , and 2 have been prepared by solid state ceramic processing and sintered at 500 and for 5 h. Thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), infrared absorption spectra (IR), and scanning electron microscopy (SEM) were used to characterize the obtained sensor pellets. It was found that no solid state reaction took place between BaTiO3and CuO during sintering process. The sensitivity of the prepared sensors to CO2gas increases with increasing sintering temperature and Ag content. The correlation between Ag content at different sintering temperature and structure characterization is discussed.

Mechanical Properties of SiC/FexSiy Composites

2011 ◽  
Vol 236-238 ◽  
pp. 1523-1527 ◽  
Author(s):  
Xiao Meng Zhang ◽  
Shu Feng Ye ◽  
Li Hua Xu ◽  
Peng Qian ◽  
Lian Qi Wei ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
High Temperature ◽  
Flexural Strength ◽  
Fracture Behavior ◽  
Room Temperature ◽  
Sintering Temperature ◽  
Raw Material ◽  
Reaction Sintering ◽  
Sintering Process ◽  
Scanning Electron

The SiC/FexSiycomposites were synthesized by reaction sintering process with iron tailings as raw material and carbon as reductant. The room and high temperature flexural strengths and fracture toughness of composites were studied in this paper. Fracture surfaces were observed by means of a scanning electron microscope (SEM). The results showed that the room temperature flexural strength of SiC/FexSiycomposites changed along with the different contents of FexSiyand sintering temperature. The flexural strength of composites reaches the maximum at 900°C. The correlation between flexural strength and temperature is consistent with curveⅠ.The fracture toughness of composites is related to the content of FexSiy. The fracture behavior of composites is mainly transcrystalline in room temperature and intercrystalline in high temperature.

Effect of Sintering Temperature on the Properties of Porous Silicon Nitride Ceramics

2009 ◽  
Vol 66 ◽  
pp. 85-88
Author(s):  
Ling Li ◽  
Yong Li ◽  
Hong Lin Yu ◽  
Fei Chen ◽  
Hong Sheng Wang ◽  
...  
Keyword(s):  
High Temperature ◽  
Silicon Nitride ◽  
Porous Silicon ◽  
Sintering Temperature ◽  
Decomposition Reaction ◽  
Sintering Process ◽  
Nitride Ceramics ◽  
Low Permittivity ◽  
Properties Of Composites

In this study, the porous silicon nitride ceramics with low permittivity was prepared by decomposition reaction of Si2N2O. The effect of sintering temperature on the properties of composites was investigated. The results show that the sintering process of porous silicon nitride ceramics is liquid crease-densititive-crease gas in high temperature-forming close pore-break of close pores and crease open pores. The density is 0.9-2.44 g/cm3, the porosity of sample varies from 0-47%, and the permittivity can be well controlled from 2.2 to 4.8.

AlN/CNT Composites Ceramics by Spark Plasma Sintering

2014 ◽  
Vol 602-603 ◽  
pp. 570-573
Author(s):  
Hai Long Liang ◽  
Chun Peng Wang ◽  
Yan Li Huo ◽  
Chuan Qi Hu ◽  
Xiao Ting Huang ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
High Temperature ◽  
Spark Plasma Sintering ◽  
Imaginary Part ◽  
Loss Factor ◽  
Sintering Temperature ◽  
Sintering Process ◽  
Composite Ceramics ◽  
Plasma Sintering ◽  
Spark Plasma

Highly dense AlN/CNT composite ceramics with 1-10% volume fractions of CNT were fabricated by spark plasma sintered (SPS) at 1400°C-1700°C. The results indicated that origination diameter of AlN had a great effect on microstructure and thermal conductivity. In details, for the system with AlN origination diameter of nanosized, the tubular structure of CNT has not been destructed, but when micro-sized AlN powder was adopted, the structure of CNT showed unstable at high temperature. Even though the degradation with incorporation of CNT into AlN, thermal conductivity of sintered AlN/CNT composites ceramics was evidently improved by adjusting content of additive Y2O3and the sintering process. Both the real part and imaginary part of the composites of Ka-Band (26.540.0 GHz) increase with the increase of CNT content, in which the increase of imaginary part is more than that of real part, resulting in an increase of loss factor. The AlN/ CNT thermal conductivity composites with appropriate CNT content and sintering temperature possess good dielectric dissipation and thermal conductivity.

Electron Microscopy of Silicon Nitride-Based Ceramics

1991 ◽  
Vol 49 ◽  
pp. 926-927
Author(s):  
Gareth Thomas
Keyword(s):  
Electron Microscopy ◽  
High Temperature ◽  
Silicon Nitride ◽  
World Wide ◽  
Sintering Temperature ◽  
Liquid Phase Sintering ◽  
High Temperature Strength ◽  
Sintering Additives ◽  
Glass Forming ◽  
Dense Product

Silicon nitride and silicon nitride based-ceramics are now well known for their potential as hightemperature structural materials, e.g. in engines. However, as is the case for many ceramics, in order to produce a dense product, sintering additives are utilized which allow liquid-phase sintering to occur; but upon cooling from the sintering temperature residual intergranular phases are formed which can be deleterious to high-temperature strength and oxidation resistance, especially if these phases are nonviscous glasses. Many oxide sintering additives have been utilized in processing attempts world-wide to produce dense creep resistant components using Si3N4 but the problem of controlling intergranular phases requires an understanding of the glass forming and subsequent glass-crystalline transformations that can occur at the grain boundaries.

Microstructural Study of Diamond Deformed Under High Pressure and Temperature

1985 ◽  
Vol 43 ◽  
pp. 230-231
Author(s):  
E. F. Koch
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Lattice Structure ◽  
Diamond Particle ◽  
Polycrystalline Diamond ◽  
Sintering Process ◽  
Ion Milling ◽  
Sintered Compact ◽  
Transmission Electron ◽  
High Pressure Sintering

Because of the extremely rigid lattice structure of diamond, generating new dislocations or moving existing dislocations in diamond by applying mechanical stress at ambient temperature is very difficult. Analysis of portions of diamonds deformed under bending stress at elevated temperature has shown that diamond deforms plastically under suitable conditions and that its primary slip systems are on the ﹛111﹜ planes. Plastic deformation in diamond is more commonly observed during the high temperature - high pressure sintering process used to make diamond compacts. The pressure and temperature conditions in the sintering presses are sufficiently high that many diamond grains in the sintered compact show deformed microtructures.In this report commercially available polycrystalline diamond discs for rock cutting applications were analyzed to study the deformation substructures in the diamond grains using transmission electron microscopy. An individual diamond particle can be plastically deformed in a high pressure apparatus at high temperature, but it is nearly impossible to prepare such a particle for TEM observation, since any medium in which the diamond is mounted wears away faster than the diamond during ion milling and the diamond is lost.

scholarly journals Microwave Sintering and Microwave Dielectric Properties of (1–x)Ca0.61La0.26TiO3-xNd(Mg0.5Ti0.5)O3 Ceramics

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 438
Author(s):  
Shuwei Yang ◽  
Bingliang Liang ◽  
Changhong Liu ◽  
Jin Liu ◽  
Caisheng Fang ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Mobile Communications ◽  
Sintering Temperature ◽  
Microwave Sintering ◽  
Microwave Dielectric Properties ◽  
Conventional Heating ◽  
Sintering Process ◽  
Microwave Dielectric ◽  
Sintering Time ◽  
Frequency Temperature

The (1–x)Ca0.61La0.26TiO3-xNd(Mg0.5Ti0.5)O3 [(1–x)CLT-xNMT, x = 0.35~0.60] ceramics were prepared via microwave sintering. The effects of sintering temperature and composition on the phase formation, microstructure, and microwave dielectric properties were investigated. The results show that the microwave sintering process requires a lower sintering temperature and shorter sintering time of (1–x)CLT-xNMT ceramics than conventional heating methods. All of the (1–x)CLT-xNMT ceramics possess a single perovskite structure. With the increase of x, the dielectric constant (ε) shows a downward trend; the quality factor (Qf) drops first and then rises significantly; the resonance frequency temperature coefficient (τf) keeps decreasing. With excellent microwave dielectric properties (ε = 51.3, Qf = 13,852 GHz, τf = −1.9 × 10−6/°C), the 0.65CLT-0.35NMT ceramic can be applied to the field of mobile communications.

Sign in / Sign up

Export Citation Format

Share Document