A long-term ultrahigh temperature application of layered silicide coated Nb alloy in air

2018 ◽  
Vol 439 ◽  
pp. 1111-1118 ◽  
Author(s):  
Jia Sun ◽  
Qian-Gang Fu ◽  
Tao Li ◽  
Chen Wang ◽  
Cai-Xia Huo ◽  
...  
Keyword(s):  
Temperature Application ◽  
Ultrahigh Temperature

Creep and Long-Term Strength of Molybdenum Alloy

2016 ◽  
Vol 843 ◽  
pp. 28-33
Author(s):  
S.P. Samoilov ◽  
A.O. Cherniavsky
Keyword(s):  
Tensile Strength ◽  
Plastic Strain ◽  
Strain Curve ◽  
Type Equation ◽  
Monotonic Loading ◽  
Molybdenum Alloy ◽  
Repeated Loading ◽  
Temperature Application ◽  
Term Creep

Mechanical behavior of a molybdenum alloy for high-temperature application was investigated at monotonic loading up to fracture, stress-and strain-controlled cyclic loading and short-term creep (less than 9 hours) under the temperatures from 293 to 1773 K using Gleeble-3800 physical simulator. The tests show that plastic strain corresponding to the tensile strength of the material under monotonic loading is small enough (<1%) whereas residual plastic strain after fracture exceeds by 50%. Repeated loading decreases the tensile strength and yield stress, but increases stable (rising) part of stress-strain curve. Increase in the test temperature leads to the change in fracture type from ductile to quasi-brittle distributed at a temperature above 1673 K. Under relatively low temperatures the rheological properties of the material depend strongly on the material processing history. Obtained creep data allows putting up a thermo-activational type equation used to calculate the steady creep rate. Coupling with the known Hoff's model for the creep prefracture stage, this equations allow not only strain rate but also adequate estimation of fracture time.

Application of STEM-EDX Mapping for Characterizing Microstructural Instabilities En 9-12% Chromium Steels With Martensitic-Austenitic Microstructure

2000 ◽  
Vol 6 (S2) ◽  
pp. 354-355
Author(s):  
U. E. Klotz ◽  
C. Solenthaler ◽  
P. J. Uggowitzer ◽  
M. O. Speidel
Keyword(s):  
Weight Percent ◽  
Tempered Martensite ◽  
High Temperature Application ◽  
Temperature Application ◽  
Cr Steels ◽  
Gas Turbine Compressor ◽  
Step Heat Treatment ◽  
Micrometer Scale ◽  
Subsequent Quenching

Materials for high-temperature application, e.g. in gas-turbine compressor discs or steam turbine rotors, are often susceptible to microstructural instabilities during long-term service. Such instabilities reduce the service life due to a deterioration of the mechanical properties. Therefore, it is most important to identify such instabilities, which often take place in sub-micrometer scale. A class of materials widely used in power generating industries are the martensitic 9-12% Cr steels. In the present work STEM-EDX mappings were used to reveal the distribution of alloying elements in 9-12% Cr steels with a martensitic-austenitic microstructure developed recently.The chemical composition of the material investigated was Fe-10.1Cr-6.2Co-5.2Mn-2.1Ni-1.2Mo-0.47V-0.1 IN (weight-percent). The material was subjected to a two step heat-treatment of normalizing at 1175°C for 1.5h with subsequent quenching and controlled tempering at 600°C for 20h. Due to the high amount of manganese and nickel a duplex microstructure of 30-40vol.% of austenite in a matrix of tempered martensite is formed during tempering.

Chemical and Proteolysis-Derived Changes during Long-Term Storage of Lactose-Hydrolyzed Ultrahigh-Temperature (UHT) Milk

2014 ◽  
Vol 62 (46) ◽  
pp. 11270-11278 ◽  
Author(s):  
Therese Jansson ◽  
Hanne B. Jensen ◽  
Ulrik K. Sundekilde ◽  
Morten R. Clausen ◽  
Nina Eggers ◽  
...  
Keyword(s):  
Uht Milk ◽  
Long Term Storage ◽  
Ultrahigh Temperature ◽  
Term Storage

Piezoelectric accelerometers for ultrahigh temperature application

2010 ◽  
Vol 96 (1) ◽  
pp. 013506 ◽  
Author(s):  
Shujun Zhang ◽  
Xiaoning Jiang ◽  
Michael Lapsley ◽  
Paul Moses ◽  
Thomas R. Shrout
Keyword(s):  
Temperature Application ◽  
Ultrahigh Temperature

A novel development of ZrB2/ZrO2 functionally graded ceramics for ultrahigh-temperature application

2008 ◽  
Vol 59 (11) ◽  
pp. 1214-1217 ◽  
Author(s):  
Xinghong Zhang ◽  
Weijie Li ◽  
Changqing Hong ◽  
Wenbo Han ◽  
Jiecai Han
Keyword(s):  
Functionally Graded ◽  
Temperature Application ◽  
Ultrahigh Temperature

Structure evolution of ZrB2–SiC during the oxidation in air

2008 ◽  
Vol 23 (7) ◽  
pp. 1961-1972 ◽  
Author(s):  
Xing-Hong Zhang ◽  
Ping Hu ◽  
Jie-Cai Han
Keyword(s):  
Room Temperature ◽  
Structure Evolution ◽  
Gravimetric Analysis ◽  
Temperature Application ◽  
Evolution Of Structure ◽  
Ultrahigh Temperature ◽  
Sic Composites ◽  
Oxidation In Air ◽  
Increasing Temperature ◽  
Apparent Influence

The structure evolution and oxidation behavior of ZrB2–SiC composites in air from room temperature to ultrahigh temperature were investigated using furnace testing, arc jet testing, and thermal gravimetric analysis (TGA). The oxide structure changed with the increasing temperature. SiC content has no apparent influence on the evolution of structure during the oxidation of ZrB2–SiC below 1600 °C. However, the evolution of structure for ZrB2–SiC above 1800 °C was significantly affected by the SiC content. The formation of the SiC depleted layer in the ZrB2–SiC system not only depends on the surrounding conditions of pressure and temperature but also on the structure distribution of the SiC in the ZrB2 matrix. The apparent recrystallization of the ZrO2 occurred above 1800 °C. The SiC content should be controlled at ∼16% in the ZrB2–SiC system for the ultrahigh-temperature application. The mechanisms of the structure evolution during oxidation in air were also analyzed.

The effect of Co and Sn on Zr-Nb alloys for high temperature application

MRS Advances ◽  
2018 ◽  
Vol 3 (37) ◽  
pp. 2151-2158
Author(s):  
M.M MALEBATI ◽  
P.E. NGOEPE ◽  
H.R. CHAUKE
Keyword(s):  
High Temperature ◽  
Nuclear Power ◽  
Nuclear Industry ◽  
Operating Conditions ◽  
High Temperature Application ◽  
Physical Strength ◽  
Operation Temperature ◽  
Temperature Application ◽  
Ternary Additions

AbstractZirconium has attracted a lot of attention recently due to its distinctive properties that make it suitable for extensive applications in the nuclear power and chemical industry. Zirconium and its alloys are undergoing long-term development as promising materials for the nuclear industry and power engineering. Recently, advanced Zr-based alloys are aimed for service in more severe operating conditions such as higher burn-up, increased operation temperature, and high-PH operation. In this work we observe the temperature dependence of Zr50Nb50, Zr78Nb22, Zr78Nb19Co3 and Zr50Nb49Sn1. It was observed that ternary additions with small atomic percentages of Co and Sn have significant impact on Zr-Nb alloy; and their elastic properties showed a possible enhancement on high temperature applications and physical strength.

Sign in / Sign up

Export Citation Format

Share Document