On the Change of Microstructure During the Hydration of Monocalcium Aluminate at 20° and 50°C

1990 ◽  
pp. 112-126
Keyword(s):  
Change Of Microstructure

The Analysis on the Starting Friction Torque Increase of Magnetic Fluid Revolving Sealing

2013 ◽  
Vol 275-277 ◽  
pp. 429-432 ◽  
Author(s):  
Yu Qiang Cai ◽  
Na Xing
Keyword(s):  
Magnetic Fluid ◽  
Magnetic Particles ◽  
Influence Factor ◽  
Magnetic Field Gradient ◽  
Friction Torque ◽  
Key Factor ◽  
Lower Temperature ◽  
Change Of Microstructure ◽  
Starting Torque ◽  
Main Influence

Abstract. Magnetic fluid revolving sealing is widely used in modern industry. In the process of application, it is founded that the starting friction torque is very large, particularly at lower temperature. This problem has become a key factor restricting the application of magnetic fluid rotation sealing. In this paper, the mechanism of starting torque increase is analyzed, based on the change of microstructure and its viscosity. After analysis , such conclusion is obtained , which can be described: to a certain sealing structure, the type of magnetic fluid, size distribution of magnetic particles as well as the working condition concluding temperature, magnetic field gradient and the revolving velocity of shaft is the main influence factor of starting friction torque . It is very useful to reduce the starting friction torque.

scholarly journals Role of Sintering Temperature in Production of Nepheline Ceramics-Based Geopolymer with Addition of Ultra-High Molecular Weight Polyethylene

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1077
Author(s):  
Romisuhani Ahmad ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Wan Mastura Wan Ibrahim ◽  
Kamarudin Hussin ◽  
Fakhryna Hannanee Ahmad Zaidi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Sintering Temperature ◽  
Ceramic Materials ◽  
Microstructural Properties ◽  
Sintering Process ◽  
Final Microstructure ◽  
Change Of Microstructure ◽  
Ultra High Molecular Weight

The primary motivation of developing ceramic materials using geopolymer method is to minimize the reliance on high sintering temperatures. The ultra-high molecular weight polyethylene (UHMWPE) was added as binder and reinforces the nepheline ceramics based geopolymer. The samples were sintered at 900 °C, 1000 °C, 1100 °C, and 1200 °C to elucidate the influence of sintering on the physical and microstructural properties. The results indicated that a maximum flexural strength of 92 MPa is attainable once the samples are used to be sintered at 1200 °C. It was also determined that the density, porosity, volumetric shrinkage, and water absorption of the samples also affected by the sintering due to the change of microstructure and crystallinity. The IR spectra reveal that the band at around 1400 cm−1 becomes weak, indicating that sodium carbonate decomposed and began to react with the silica and alumina released from gels to form nepheline phases. The sintering process influence in the development of the final microstructure thus improving the properties of the ceramic materials.

Glass-Forming Ability and Thermal Stability of Gd55-xNdxCo20Al25 Metallic Glass

2013 ◽  
Vol 538 ◽  
pp. 270-273
Author(s):  
Li Li Zhang ◽  
Qi Jun Huang ◽  
Zhi Qin Liao ◽  
Feng Xu ◽  
Guang Chen ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Amorphous Ribbon ◽  
Glass Forming Ability ◽  
X Ray Diffraction ◽  
Glass Transition Temperatures ◽  
X Ray ◽  
Glass Forming ◽  
Nd Substitution ◽  
Change Of Microstructure ◽  
Thermal Stability Of

The effects of Nd substitution in Gd55-xNdxCo20Al25 (x=0, 5, 10, 15 and 20) amorphous ribbon samples on glass-forming ability and thermal stability are studied. The change of microstructure cannot be identified by X-ray diffraction. The forecast of glass-forming ability following Fang’s method shows the increase with x, which is further confirmed experimentally by the increasing reduced glass-transition temperatures. The thermal stability has a minimum at x=10, and it is suggested to be due to the different effects of the reducing of Gd and the increase of Nd.

scholarly journals Understanding the Relations between Surface Stress State and Microstructure Feature for Enhancing the Fatigue Performance of TC6 Titanium Alloy

Coatings ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1261
Author(s):  
Song Shu ◽  
Xin Huang ◽  
Zonghui Cheng ◽  
Yizhou Shen ◽  
Zhaoru He ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Fatigue Life ◽  
Stress State ◽  
Surface Stress ◽  
Strengthening Mechanism ◽  
Fatigue Performance ◽  
Shock Peening ◽  
The Relationship ◽  
Change Of Microstructure ◽  
Improve Fatigue

Fatigue performance has always been an important factor affecting the application of titanium alloy. The service life of TC6 titanium alloy is easily reduced under a continuously alternating load. Therefore, there is an urgent need for a new method to improve fatigue performance. Laser shock peening (LSP) is a widely proposed method to enhance the fatigue performance. Here, through experiments and finite element simulations, it was found that LSP can prolong the fatigue life of TC6 by improving the surface stress state. In strengthening processes, the generation of residual stress was mainly attributed to the change of microstructure, which could be reflected by the statistical results of grain sizes. The content of grains with a size under 0.8 μm reached 78%, and the microhardness value of treated TC6 was 18.7% higher than that of an untreated sample. In addition, the surface residual compressive stress was increased to −600 MPa at the depth of 1500 μm from the surface. On this basis, the fatigue life was prolonged to 135%, and the ultimate fracture macroscopic was also changed. With the treatment of LSP, the fatigue performance of TC6 is highly promoted. The strengthening mechanism of LSP was established with the aim of revealing the relationship between microstructure and stress state for enhancing the fatigue performance in whatever shapes.

Degradation Properties of Hydrogen Storage Alloys and Change of Microstructure during the Degradation

2007 ◽  
pp. 1613-1616
Author(s):  
Hideaki Tanaka ◽  
Song Han ◽  
Qiang Xu ◽  
Nobuhiro Kuriyama ◽  
K. Aihara ◽  
...  
Keyword(s):  
Hydrogen Storage ◽  
Hydrogen Storage Alloys ◽  
Degradation Properties ◽  
Change Of Microstructure

Change of Microstructure Evaluation during Fatigue of Stainless Steel in Power Plants

2016 ◽  
Vol 2016.24 (0) ◽  
pp. 905
Author(s):  
Yosuke INOUE ◽  
Shuhei KOZU ◽  
Tomoya SENDA ◽  
Takashi NAGOSHI ◽  
Yoshihisa HARADA ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Power Plants ◽  
Microstructure Evaluation ◽  
Change Of Microstructure

Research on the Microstructure and Properties of Hypereutectic Al-Si Alloy for Semi-Solid Forming during Heat Treatment

2014 ◽  
Vol 887-888 ◽  
pp. 349-356
Author(s):  
Xiang Fan ◽  
Yi Tao Yang
Keyword(s):  
Heat Treatment ◽  
Treatment Process ◽  
Solution Temperature ◽  
Heat Treatment Process ◽  
Aluminum Silicon Alloy ◽  
Liquid Line ◽  
And Performance ◽  
Semi Solid ◽  
Change Of Microstructure ◽  
Microstructure And Performance

The heat treatment process of a kind of hypereutectic aluminum silicon alloy which is suitable for semi-solid forming and the change of microstructure and performance during the process of heat treatment had been studied in this paper. In order to guide the heat treatment process, the phase diagram of the alloy had been calculated by the software of Thermo-Calc, and the theoretical solid and liquid line had been gotten. Twelve kinds of heat treatment process had been selected in this study. Finally the best process which the solution temperature is 495°C for 2h and aging temperature is 160°C for 8h had been gotten.

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