Preparation of MoSi2 Coating on Mo Substrate for Oxidation Resistance by a Facile Method

2021 ◽  
Vol 16 (2) ◽  
pp. 230-234
Author(s):  
Shuchen Sun ◽  
Jiahang Qiu ◽  
Mu Zhang ◽  
Ruizhi Guo ◽  
Zhimeng Xiu ◽  
...  
Keyword(s):  
Oxidation Resistance ◽  
Coating Layer ◽  
Sintering Process ◽  
Hot Press ◽  
Combined Method ◽  
Mosi2 Coating ◽  
Embedded Method ◽  
Hot Press Sintering ◽  
Poor Oxidation Resistance

A MoSi2 coating layer with a MoB protected layer was simply prepared by using a combined method, which involved slurry painting and an embedded method via a hot press sintering process. The microstructure and phase composition of the coatings were investigated and determined. The experimental time and the B addition are considered as important factors to be discussed in this study. All the results proved that when B is added, it was found that the formation of MoB played an important role of a diffusion barrier to Si and hindered the production of the poor oxidation resistance phases (Mo5Si3 and Mo3Si).

Effect of Sintering Process on Microstructure of Al2O3/LiTaO3 Composite Ceramics

2007 ◽  
Vol 336-338 ◽  
pp. 2363-2365
Author(s):  
You Feng Zhang ◽  
Yu Zhou ◽  
De Chang Jia ◽  
Qing Chang Meng
Keyword(s):  
Grain Boundaries ◽  
Relative Density ◽  
Theoretical Density ◽  
Pressureless Sintering ◽  
Sintering Process ◽  
Hot Press ◽  
Composite Ceramics ◽  
Fine Grained ◽  
N2 Atmosphere ◽  
Hot Press Sintering

Effects of different sintering methods such as pressureless sintering and hot press sintering on relative density and microstructure of the Al2O3p/LiTaO3 (ALT) composite ceramics were investigated to obtain a preferable sintering process. Relative densities of all ALT composites are below 90% when sintered with the cold isostatical pressing followed by pressureless sintering at temperatures of 1250 to 1350°C. The relative densities and microstructure of ALT composite ceramics with the hot press sintering process in a N2 atmosphere at 1150 and 1300°C were investigated. The relative density of ALT composite hot pressed at 1150°C is only 77%, and almost theoretical density at 1300°C. This indicates that sintering pressure plays an important role in the densification of ALT composite ceramics in temperature range of 1150 to 1350°C. Investigation on morphologies of the composites shows that the Al2O3 particles distributed along grain boundaries of LiTaO3, which leads to a fine-grained microstructure in the ALT composite ceramics

Sintering of β-Si3N4 Powder Prepared by Self-Propagating High-Temperature Synthesis (SHS)

2007 ◽  
Vol 546-549 ◽  
pp. 2179-2182 ◽  
Author(s):  
Ling Bai ◽  
Xing Yu Zhao ◽  
Chang Chun Ge
Keyword(s):  
High Temperature ◽  
Silicon Nitride ◽  
Bending Strength ◽  
Sintering Process ◽  
Hot Press ◽  
Temperature Synthesis ◽  
High Temperature Synthesis ◽  
Good Sinter ◽  
The Cost ◽  
Hot Press Sintering

Sintering of the Self-Propagating High-Temperature Synthesis (SHS) of β-Si3N4 powder with 6.67 wt.% Y2O3 and 3.33 wt.% Al2O3 as sintering additives has been emphatically investigated using hot-press sintering process. The relative density of hot-pressed β-Si3N4 reached near to the full densification (99.43%) at 1700°C. The similar micrographs with self-reinforcing rod-like β-Si3N4 grains forming an interlocking structure were observed. The better mechanical properties of hot-pressed Si3N4, such as the hardness (16.73GPa), fracture toughness (5.72 MPa·m1/2) and bending strength (611.72MPa) values, were obtained at 1700°C. The results indicate that good sinter ability can be obtained with the cheaply SHS of silicon nitride powder for preparing silicon nitride materials, which will make the cost of silicon nitride materials lowered.

scholarly journals Study on the Influence of the New Type of Powder Metallurgy Ti-Al-Nb Alloy Hot Press Sintering Process on the Microstructure

2021 ◽  
Vol 299 ◽  
pp. 03010
Author(s):  
Shuang Fang ◽  
Mincong Zhang ◽  
Qiuying Yu ◽  
Huaping Xiong
Keyword(s):  
Hot Pressing ◽  
Room Temperature ◽  
Raw Material ◽  
Sintering Process ◽  
Hot Press ◽  
New Type ◽  
Hot Pressing Sintering ◽  
Hot Press Sintering ◽  
Kinetics Of ◽  
Material Powder

Based on the hot-pressing sintering process, the kinetics of hot-pressing sintering crystal grain growth and the hot-pressing sintering densification kinetics, the mixing ratio of the raw material powder and the hot-pressing sintering system are designed. The pressure is maintained at 30 MPa from the temperature rise to the end of the sintering process, and wait until the temperature reaches the corresponding hot pressing sintering temperature (1200°C~1400°C), keep the corresponding time for 1.5h~4.5h, stop heating and depressurize, and the alloy billet is cooled to room temperature with the furnace. The main phases of Ti2AlNb powder and hot pressing sintering process are TiAl and Ti3Al.

Fabrication of a SiC-Ti Functionally Graded Bonding Interlayer by Precursor Method

2013 ◽  
Vol 745-746 ◽  
pp. 696-699
Author(s):  
Hong Li Liu ◽  
Shi You Hu ◽  
Jiu Jun Yang ◽  
Xue Lian Zhao ◽  
Bai Shen Qiu
Keyword(s):  
Ceramic Matrix ◽  
Functionally Graded ◽  
Sintering Process ◽  
Hot Press ◽  
Precursor Method ◽  
Compact Structure ◽  
Connection Problem ◽  
Distribution Of Elements ◽  
Graded Material ◽  
Hot Press Sintering

SiC-Ti functionally graded material (FGM) was prepared by polymer-derived method in order to resolve connection problem between the ceramic matrix and its composite materials, as well as metal at high-temperature. Gradient materials were fabricated successfully by polymer-derived method combined with hot-press sintering process at 1300. The microstructure of the prepared samples was studied, and the results revealed that this FGM had a compact structure, without obvious interface between different layers. The distribution of elements was gradient according to the SEM and EDX results.

A Study on Manufacture of SiCp/Fe Composites by Specimen Current Heating Hot Press Sintering

2007 ◽  
Vol 561-565 ◽  
pp. 705-708 ◽  
Author(s):  
Gang Wang ◽  
Yu Fang Yang ◽  
Ya Ping Zong
Keyword(s):  
Brinell Hardness ◽  
Heating Surface ◽  
Sintering Process ◽  
Hot Press ◽  
Fast Heating ◽  
Sintering Time ◽  
Fine Microstructure ◽  
Hot Press Sintering ◽  
Particulate Reinforced ◽  
Oxidation Degradation

A specimen current heating sintering process was employed to manufacture SiC particulate reinforced iron matrix composite. The results show that mechanical properties of the composite can be improved significantly with increasing pressure level, voltage, sintering time. It is found that short sintering time, fast heating and uniformly heating, surface activation of particles can be accomplished in specimen current heating hot press sintering to avoid oxidation degradation of Fe powder, and to produce fine microstructure, which contribute the main reasons for achieving higher density and higher properties. The best properties achieved so far for the composite are: density is 99.90%, Brinell hardness is 416HB and tensile strength is 838MPa.

Fabrication and Properties of SrBi2(Ta1-xNbx)2O9 Ferroelectric Ceramics

2007 ◽  
Vol 336-338 ◽  
pp. 143-145
Author(s):  
Wen Wang ◽  
Ke Yu ◽  
Hua Ke ◽  
Hai Jun Niu ◽  
De Chang Jia ◽  
...  
Keyword(s):  
Perovskite Structure ◽  
Remanent Polarization ◽  
Ferroelectric Ceramics ◽  
Layered Perovskite ◽  
Sintering Process ◽  
Hot Press ◽  
Grain Sizes ◽  
Nb Content ◽  
Layered Perovskite Structure ◽  
Hot Press Sintering

SrBi2(Ta1-xNbx)2O9(SBTN) ferroelectric ceramics with typical bismuth layered perovskite structure were synthesized with a reactive hot-press sintering process at 1000°C for 2h. The as-sintered SBTN (x=0.2, 0.4, 0.6, 0.8) materials had a maximum relative density of 95.97%. Bi-layered perovskite structure was obtained. The grain sizes increased with increasing Nb content. In 1MHz frequency, remanent polarization (Pr) of SBTN (x=0.2, 0.4, 0.6, 0.8) were 10.0, 3.0, 1.7 and 1.0, while coercive field (Ec) of SBTN (x=0.2, 0.4, 0.6, 0.8) were 50, 32, 33 and 33kV/cm, respectively.

Investigation on the fabrication of dicing blades with different sintering methods for machining hard-brittle material wafers

2018 ◽  
Vol 233 (7) ◽  
pp. 1781-1793 ◽  
Author(s):  
Zewei Yuan ◽  
Kai Cheng ◽  
Yiheng Zhang ◽  
Jintao Hu ◽  
Peng Zheng
Keyword(s):  
Spark Plasma Sintering ◽  
Sintering Process ◽  
Hot Press ◽  
Vacuum Sintering ◽  
Innovative Design ◽  
Plasma Sintering ◽  
Chip Size ◽  
Spark Plasma ◽  
Hot Press Sintering ◽  
Sintering Method

Hard-brittle materials applied in various micro-electromechanical systems should be sliced into miniature and microparts often with complex microstructures. However, it is difficult for bladed dicing to machine those materials without damage because of their hard and brittle properties. This article presents innovative design and fabrication of dicing blades and the associated dicing process optimization, particularly by focusing on the blade wheel fabrication through sintering methods including traditional hot press sintering, vacuum sintering and spark plasma sintering. Four key parameters, namely, the radial wear of the dicing blade, the current of relay, the number of chips larger than 50 μm and the largest chip size, are employed to assess the cutting performance of dicing blades fabricated. The analysis and experimental results indicate that the spark plasma sintering method achieves the lowest number of chips and the smallest chip size due to its rapid spark between metal particles during the sintering process. The spark plasma sintering method can also produce a granular microstructure with sufficient porosities, which results in uniform bonding strength of diamond abrasive grits within the dicing blade. For the dicing process parameters, the back cutting depth has the most obvious influence on the dicing blade tool life, cutting current and slicing damages, while the feed rate is ranked the next. The least influencing parameter is the dicing spindle rotational speed.

Consolidation and Properties of Tungsten Carbide Target with Low Cobalt Content by Hot-Press Sintering

2007 ◽  
Vol 351 ◽  
pp. 98-102
Author(s):  
Gang Qin Shao ◽  
Z. Xiong ◽  
T.G. Wang ◽  
Xiao Liang Shi ◽  
Xing Long Duan
Keyword(s):  
Tungsten Carbide ◽  
Relative Density ◽  
Diffusion Rate ◽  
Cobalt Content ◽  
Sintering Process ◽  
Hot Press ◽  
In Situ Reaction ◽  
High Relative Density ◽  
Hot Press Sintering

Tungsten carbide (WC) targets with low cobalt (Co) content (0.1 - 0.2 wt.%) were prepared by hot-press sintering at 1700°C for 60 minutes in argon, from element starting powders of tungsten, cobalt and carbon. Results show that the as-fabricated targets yield relatively high relative density above 99% and high HRA above 92. WC with low Co content is formed easily than pure WC. The hot-press sintering process, while element starting powders are used, is an in-situ reaction technique for accelerating the WC’s diffusion rate to obtain a dense sintered body.

scholarly journals Microstructural Evolution of H-BN Matrix Composite Ceramics With Amorphous La2O3-Al2O3-SiO2 Glass Phase During Hot Pressing

2020 ◽  
Author(s):  
Baofu Qiu ◽  
Xiaoming Duan ◽  
Zhuo Zhang ◽  
Chen Zhao ◽  
Bo Niu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Microstructural Evolution ◽  
Glass Phase ◽  
Sintering Temperature ◽  
Raw Materials ◽  
Sintering Process ◽  
Hot Press ◽  
Composite Ceramics ◽  
Phase Precipitation ◽  
Hot Press Sintering

Abstract BN-La2O3-Al2O3-SiO2 composite ceramics were fabricated by hot press sintering using h-BN, La2O3, Al2O3 and amorphous SiO2 as the raw materials. The effects of sintering temperature on the microstructural evolution, bulk density, apparent porosity, and mechanical properties of h-BN composite ceramics were investigated. The results indicated that ternary La2O3-Al2O3-SiO2 liquid phase was formed during sintering process, which provided an environment for the growth of h-BN grains. With increasing sintering temperature, the cristobalite phase precipitation and h-BN grain growth occurred at the same time, which had the significant influence on the densification and mechanical properties of h-BN composite ceramics. The best mechanical properties of BN-La2O3-Al2O3-SiO2 composite ceramics were obtained under sintering temperature of 1700 °C, and the elastic modulus, flexural strength, and fracture toughness were 80.5 GPa, 266.4 MPa and 3.25 MPa·m1/2, respectively.

Sign in / Sign up

Export Citation Format

Share Document