scholarly journals The Analysis of the Microstructure of Welded Joints in Steel P5 after Service

2020 ◽  
pp. 7-12
Author(s):  
Agata Merda ◽  
Grzegorz Golański ◽  
Paweł Wieczorek ◽  
Kamil Staszałek
Keyword(s):  
Elevated Temperature ◽  
Low Temperature ◽  
Welded Joint ◽  
Bainitic Steel ◽  
Joint Microstructure ◽  
Pipe Section ◽  
Low Degree ◽  
Austenite Grains ◽  
Short Time ◽  
M23c6 Carbides

The material subjected to the tests discussed in the article was a section of a welded joint made of bainitic steel P5. The joint subjected to analysis was sampled from a pipe section exposed to the effect of elevated temperature for more than 96 000 hours. The metallurgical tests revealed a relatively low degree of the degradation of the test joint. The microstructure contained retained bainite and precipitates of various morphology. The identification of precipitates revealed the presence of M23C6 and M2C precipitates in the joint. The M23C6 carbides were observed along the boundaries of former austenite grains. The above-named identification of precipitates also revealed the presence of M2C and M23C6 C6 carbides within the grains/laths. The insignificant exhaustion of the joint microstructure might be ascribed to the fact that the joint was subjected to relatively low temperature for a relatively short time.

Progress of Research on Welding for Molybdenum Alloys

2014 ◽  
Vol 33 (3) ◽  
pp. 193-200 ◽  
Author(s):  
Jiteng Wang ◽  
Juan Wang ◽  
Yajiang Li ◽  
Deshuang Zheng
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Low Temperature ◽  
Welded Joint ◽  
Structural Materials ◽  
Practical Applications ◽  
Traditional Technology ◽  
Molybdenum Alloys ◽  
Resistance To Oxidation ◽  
Temperature Applications

AbstractMolybdenum and molybdenum alloys are considered to be attractive structural materials for high-temperature applications. However, molybdenum alloys are sensitive to gas impurities and have the characteristics of low temperature embrittlement and less resistance to oxidation at elevated temperature. The toughness and strength of welded joint is not easy to be ensured by traditional technology. Recently, many efforts have been made to join molybdenum and its alloys. In this paper, we present the result of investigations on welding methods of molybdenum and its alloys and overview the practical applications in engineering. The key of joining molybdenum alloys is to improve the toughness of welded joint and prevent the generation of pores and cracks.

scholarly journals The effect of a novel low temperature-short time (LTST) process to extend the shelf-life of fluid milk

SpringerPlus ◽  
2016 ◽  
Vol 5 (1) ◽  
Author(s):  
Phillip R. Myer ◽  
Kyle R. Parker ◽  
Andrew T. Kanach ◽  
Tengliang Zhu ◽  
Mark T. Morgan ◽  
...  
Keyword(s):  
Low Temperature ◽  
Shelf Life ◽  
Short Time ◽  
Fluid Milk

Morphogenesis in hydra

Development ◽  
1970 ◽  
Vol 24 (1) ◽  
pp. 21-32
Author(s):  
Sondra C. Corff ◽  
Allison L. Burnett
Keyword(s):  
Nervous System ◽  
Cell Division ◽  
Hydrostatic Pressure ◽  
Low Temperature ◽  
Low Temperatures ◽  
Mitotic Division ◽  
Basal Disc ◽  
Dividing Cells ◽  
Short Time ◽  
Disc Formation

When Hydra oligactis is excised below the tentacles and incubated for a short time in concentrations of colchicine that inhibit spindle formation in dividing cells, a peduncle and basal disc subsequently form at the cut distal end, where hypostome and tentacles normally form (Corff & Burnett, 1969). Since recent reports suggest a similarity in the action of colchicine and low temperature, in this study the effects of low temperatures on regenerating hydra were investigated. High hydrostatic pressure and low temperature have been shown to act synergistically with colchicine to inhibit the first mitotic division in sea urchin eggs (Marsland, 1968). Colchicine and cooling have also been shown to cause disintegration of the microtubule system in Actinosphaerium (Tilney, 1965). We have previously discussed peduncle and basal disc formation at the distal end in terms of colchicine inhibition of cell division and the possible action of colchicine on the nervous system (Corff & Burnett, 1969).

scholarly journals Challenging the thorium-immobility paradigm

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Haylea Nisbet ◽  
Artas A. Migdisov ◽  
Anthony E. Williams-Jones ◽  
Hongwu Xu ◽  
Vincent J. van Hinsberg ◽  
...  
Keyword(s):  
Elevated Temperature ◽  
Low Temperature ◽  
Nuclear Fuel ◽  
Fuel Cycle ◽  
Nuclear Fuel Cycle ◽  
Hydrothermal Fluids ◽  
Solubility Data ◽  
Aqueous Systems ◽  
Hydrothermal Deposits ◽  
High Concentrations

AbstractThorium is the most abundant actinide in the Earth’s crust and has universally been considered one of the most immobile elements in natural aqueous systems. This view, however, is based almost exclusively on solubility data obtained at low temperature and their theoretical extrapolation to elevated temperature. The occurrence of hydrothermal deposits with high concentrations of Th challenges the Th immobility paradigm and strongly suggests that Th may be mobilized by some aqueous fluids. Here, we demonstrate experimentally that Th, indeed, is highly mobile at temperatures between 175 and 250 °C in sulfate-bearing aqueous fluids due to the formation of the highly stable Th(SO4)2 aqueous complex. The results of this study indicate that current models grossly underestimate the mobility of Th in hydrothermal fluids, and thus the behavior of Th in ore-forming systems and the nuclear fuel cycle needs to be re-evaluated.

Profiling Different Kinds of Generated Defects at Elevated Temperature in Both SiO2 and High-k Dielectrics

2010 ◽  
Vol 1252 ◽  
Author(s):  
Sahar Sahhaf ◽  
Robin Degraeve ◽  
Mohammed Zahid ◽  
Guido Groeseneken
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Low Temperature ◽  
Leakage Current ◽  
Charge Injection ◽  
Constant Voltage ◽  
High K ◽  
Voltage Stress ◽  
Stress Induced Leakage Current ◽  
High K Dielectric

AbstractIn this work, the effect of elevated temperature on the generated defects with constant voltage stress (CVS) in SiO2 and SiO2/HfSiO stacks is investigated. Applying Trap Spectroscopy by Charge Injection and Sensing (TSCIS) to 6.5 nm SiO2 layers, different kinds of generated traps are profiled at low and high temperature. Also the Stress-Induced Leakage Current (SILC) spectrum of high-k dielectric stack is different at elevated temperature indicating that degradation and breakdown at high temperature is not equivalent to that at low temperature and therefore, extrapolation of data from high to low T or vice versa is challenging.

Low Temperature (<150°C) Doping Techniques for Polysilicon TFT's

2004 ◽  
Vol 808 ◽  
Author(s):  
W.S. Hong ◽  
J.M. Kim ◽  
S.H. Han ◽  
Y.H. Lee ◽  
Y.W. Kim ◽  
...  
Keyword(s):  
Low Temperature ◽  
Sheet Resistance ◽  
Structural Damage ◽  
Laser Energy ◽  
Good Alternative ◽  
Immersion Method ◽  
Dopant Activation ◽  
Layer Deposition ◽  
Si Films ◽  
Short Time

ABSTRACTDoping of polysilicon (poly-Si) films was performed at a low temperature (<150°C), by using three different dopant incorporation methods: ion shower, dopant layer deposition and plasma immersion. All three techniques were shown to be capable of obtaining sheet resistance values that were smaller than 104 Ω/sq., which were considered to be sufficient to form good source-drain contacts. Also, a sheet resistance value that is as low as 300 Ω/sq. was demonstrated. It was found that the laser energy used for dopant activation was the major parameter to control the sheet resistance of the poly-Si films. The lowest attainable sheet resistance was not affected much by the ion dose, as long as the initial dose is higher than 1015 cm−2. The plasma immersion method was shown to be a good alternative to the ion shower, as the doping could be performed in a relatively short time without causing a structural damage to the poly-Si film.

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