The effect of zirconia sintering temperature on flexural strength, grain size, and contrast ratio

AbstractThe synthesis, microstructure, and properties of high purity dense bulk Mo2TiAlC2 ceramics were studied. High purity Mo2TiAlC2 powder was synthesized at 1873 K starting from Mo, Ti, Al, and graphite powders with a molar ratio of 2:1:1.25:2. The synthesis mechanism of Mo2TiAlC2 was explored by analyzing the compositions of samples sintered at different temperatures. It was found that the Mo2TiAlC2 phase was formed from the reaction among Mo3Al2C, Mo2C, TiC, and C. Dense Mo2TiAlC2 bulk sample was prepared by spark plasma sintering (SPS) at 1673 K under a pressure of 40 MPa. The relative density of the dense sample was 98.3%. The mean grain size was 3.5 μm in length and 1.5 μm in width. The typical layered structure could be clearly observed. The electrical conductivity of Mo2TiAlC2 ceramic measured at the temperature range of 2–300 K decreased from 0.95 × 106 to 0.77 × 106 Ω–1·m–1. Thermal conductivity measured at the temperature range of 300–1273 K decreased from 8.0 to 6.4 W·(m·K)–1. The thermal expansion coefficient (TEC) of Mo2TiAlC2 measured at the temperature of 350–1100 K was calculated as 9.0 × 10–6 K–1. Additionally, the layered structure and fine grain size benefited for excellent mechanical properties of low intrinsic Vickers hardness of 5.2 GPa, high flexural strength of 407.9 MPa, high fracture toughness of 6.5 MPa·m1/2, and high compressive strength of 1079 MPa. Even at the indentation load of 300 N, the residual flexural strength could hold 84% of the value of undamaged one, indicating remarkable damage tolerance. Furthermore, it was confirmed that Mo2TiAlC2 ceramic had a good oxidation resistance below 1200 K in the air.

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Biaxial flexural strength, crystalline structure, and grain size of new commercially available zirconia-based ceramics for dental appliances produced using a new slip-casting method

Journal of the Mechanical Behavior of Biomedical Materials ◽

10.1016/j.jmbbm.2020.104180 ◽

2020 ◽

pp. 104180

Author(s):

Jean-François Roulet ◽

Kristy Lee Schepker ◽

Andres Truco ◽

Hans-Christoph Schwarz ◽

Mateus Garcia Rocha

Keyword(s):

Grain Size ◽

Flexural Strength ◽

Crystalline Structure ◽

Slip Casting ◽

Casting Method ◽

Biaxial Flexural Strength

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Effect of Sintering Temperature on Microstructure and Mechanical Properties of Al2O3-TiC-ZrO2 Ceramic Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.1031 ◽

2012 ◽

Vol 476-478 ◽

pp. 1031-1035

Author(s):

Wei Min Liu ◽

Xing Ai ◽

Jun Zhao ◽

Yong Hui Zhou

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Fracture Toughness ◽

Flexural Strength ◽

Relative Density ◽

Sintering Temperature ◽

Ceramic Composites ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

Al2O3-TiC-ZrO2ceramic composites (ATZ) were fabricated by hot-pressed sintering. The phases and microstructure of the composites were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The relative density and mechanical properties (flexural strength, fracture toughness and Vicker’s hardness) of the composites were tested. The results show that the microstructure of the composites was the gray core-white rim. With the increase of sintering temperature, the relative density and mechanical properties of the composites increased first and then decreased. The composite sintered at 1705°C has the highest synthetical properties, and its relative density, flexural strength, fracture toughness and Vickers hardness are 98.3%,970MPa,6.0 MPa•m1/2and 20.5GPa, respectively.

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Preparation and Electrical Property of Calcia Stabilized Zirconia Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.616.157 ◽

2014 ◽

Vol 616 ◽

pp. 157-165 ◽

Cited By ~ 3

Author(s):

Chang Lian Chen ◽

Hong Quan Wang ◽

Jia You Ji ◽

Ma Ya Luo ◽

Bo Wu ◽

...

Keyword(s):

Grain Size ◽

Electrical Property ◽

Arrhenius Equation ◽

Sintering Temperature ◽

Raw Materials ◽

Cubic Phase ◽

Pressureless Sintering ◽

Stabilized Zirconia ◽

Zirconia Ceramics ◽

Sintering Method

In this paper, using ZrO2 and Ca (NO3)•4H2O as raw materials, we prepared a series of calica stabilized zirconia (CSZ) ceramics by pressureless sintering method. The results show that the relative densities of all sintered samples are above 90%, and the sintered samples are composed of cubic, tetragonal and monoclinic ZrO2, and the main phase is cubic ZrO2 and tetragonal ZrO2. The content of cubic phase increases with the increase of sintering temperature and adding CaO content. The grain size of the sintered samples is relatively uniform and some pores exist. Increasing the additive amount of CaO, the conductivity first rises and then decreases, and the conductivity value of the sample containing 5wt% CaO is the maximum. When the sintering temperature is up to 1600 oC, the conductivity of the sample containing 5wt% CaO is up to 0.016S•cm-1 at 800 oC. Furthermore, the conductivity of sintered samples is increasing with the increase of test temperature according to the Arrhenius equation.

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Fabrication of (SiC-AlN)/ZrB2 Composite with Nano-Micron Hybrid Microstructure via PCS-Derived Ceramics Route

Materials ◽

10.3390/ma14020334 ◽

2021 ◽

Vol 14 (2) ◽

pp. 334

Author(s):

Aidong Xia ◽

Jie Yin ◽

Xiao Chen ◽

Zhengren Huang ◽

Xuejian Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Flexural Strength ◽

Hot Pressing ◽

Raw Materials ◽

Secondary Phase ◽

Pressing Temperature ◽

Xrd Pattern ◽

Mean Grain Size ◽

The Mean

In this work, a (SiC-AlN)/ZrB2 composite with outstanding mechanical properties was prepared by using polymer-derived ceramics (PDCs) and hot-pressing technique. Flexural strength reached up to 460 ± 41 MPa, while AlN and ZrB2 contents were 10 wt%, and 15 wt%, respectively, under a hot-pressing temperature of 2000 °C. XRD pattern-evidenced SiC generated by pyrolysis of polycarbosilane (PCS) was mainly composed by 2H-SiC and 4H-SiC, both belonging to α-SiC. Micron-level ZrB2 secondary phase was observed inside the (SiC-AlN)/ZrB2 composite, while the mean grain size (MGS) of SiC-AlN matrix was approximately 97 nm. This unique nano-micron hybrid microstructure enhanced the mechanical properties. The present investigation provided a feasible tactic for strengthening ceramics from PDCs raw materials.

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Sintering behavior and ionic conductivity of Li1.5Al0.5Ti1.5(PO4)3 synthesized with different precursors

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2021-3090 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Bambar Davaasuren ◽

Qianli Ma ◽

Alexandra von der Heiden ◽

Frank Tietz

Keyword(s):

Grain Size ◽

Solid State ◽

Ionic Conductivity ◽

Solid State Reaction ◽

Sintering Temperature ◽

Sintering Behavior ◽

Homogeneous Microstructure ◽

Micro Cracks ◽

Primary Particles ◽

Total Ionic Conductivity

Abstract Li1.5Al0.5Ti1.5(PO4)3 (LATP) powders were prepared from different NO x -free precursors using an aqueous-based solution-assisted solid-state reaction (SA-SSR). The sintering behavior, phase formation, microstructure and ionic conductivity of the powders were explored as a function of sintering temperature. The powders showed a relatively narrow temperature windows in which shrinkage occurred. Relative densities of 95% were reached upon heating between 900 and 960 °C. Depending on the morphological features of the primary particles, either homogeneous and intact microstructures with fine grains of about <2 µm in size or a broad grain size distribution, micro-cracks and grain cleavages were obtained, indicating the instability of the microstructure. Consequently, the ceramics with a homogeneous microstructure possessed a maximum total ionic conductivity of 0.67 mS cm−1, whereas other ceramics reached only 0.58 mS cm−1 and 0.21 mS cm−1.

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Effect of Sintering Temperature on the Microstructure, Electrical and Magnetotransport Properties of La0.67Sr0.33MnO3 Compound

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.895.319 ◽

2014 ◽

Vol 895 ◽

pp. 319-322

Author(s):

Lim Kean Pah ◽

Abdul Halim Shaari ◽

Chen Soo Kien ◽

Chin Hui Wei ◽

Albert Gan ◽

...

Keyword(s):

Grain Size ◽

Single Phase ◽

Sintering Temperature ◽

Measurement Range ◽

Hexagonal Structure ◽

Precipitation Method ◽

Metal Insulator ◽

Higher Temperature ◽

Co Precipitation ◽

Grain Surface

In this work, we report the effect of sintering temperature (900°C, 1000°C, 1100°C and 1200°C) on the electrical and magnetotransport properties of polycrystalline La0.67Sr0.33MnO3 (LSMO). Single phase of LSMO hexagonal structure (R-3c) accompanied with minor phases was successfully synthesized by co-precipitation method. With increasing sintering temperature, grain growth was promoted and grain connectivity was improved. It was found that an enhancement of resistivity on smaller grain size was due to larger grain surface over volume (grain boundaries effect). The shifting of the metal-insulator transition (TMI) to higher temperature was also responsible for observed changes in physical properties. TMI of 900°C, 1000°C and 1100°C were 232 K, 278 K and 298 K respectively however 1200°C was out of measurement range (higher than 300 K). In summary, CP900 with smaller grain size distribution (~200 nm) displayed the highest resistivity and MR% of -19.2% (at 80 K, 10 kG).

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Effect of Fly Ash on the Properties of Ceramics Prepared from Steel Slag

Applied Sciences ◽

10.3390/app8071187 ◽

2018 ◽

Vol 8 (7) ◽

pp. 1187 ◽

Cited By ~ 5

Author(s):

Yanbing Zong ◽

Xuedong Zhang ◽

Emile Mukiza ◽

Xiaoxiong Xu ◽

Fei Li

Keyword(s):

Fly Ash ◽

Flexural Strength ◽

Water Absorption ◽

Sintering Temperature ◽

Steel Slag ◽

Diffraction Peak ◽

National Standard ◽

Sintered Ceramic ◽

Base Steel ◽

Sintering Shrinkage

In this study, SiO2–Al2O3–CaO–MgO steel slag ceramics containing 5 wt % MgO were used for the preparation of ceramic bodies, with the replacement of 5–20 wt % quartz and feldspar by fly ash. The effect of the addition of fly ash on the sintering shrinkage, water absorption, sintering range, and flexural strength of the steel slag ceramic was studied. Furthermore, the crystalline phase transitions and microstructures of the sintered samples were investigated by XRD, Fourier transform infrared (FTIR), and SEM. The results showed that the addition of fly ash affected the crystalline phases of the sintered ceramic samples. The main crystal phases of the base steel slag ceramic sample without fly ash were quartz, diopside, and augite. With increasing fly ash content, the quartz diffraction peak decreased gradually, while the diffraction peak intensity of anorthite became stronger. The mechanical properties of the samples decreased with the increasing amount of fly ash. The addition of fly ash (0–20 wt %) affected the optimum sintering temperature (1130–1160 °C) and widened the sintering range. The maximum addition amount of fly ash should be 15 wt %, for which the optimum sintering temperature was 1145 °C, water absorption was 0.03%, and flexural strength was 43.37 MPa higher than the Chinese national standard GBT 4100-2015 requirements.

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