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-This paper originates from a large EU programme designed to produce high performance coatings with superior mechanical and corrosion resistance properties to enhance high temperature corrosion behaviour of TiAl based alloy (Ti45Al8Nb).The paper here is concerned with studies of the hot corrosion behaviour of Ti - Aluminide alloys (Ti45Al8Nb mainly -TiAl with small amount 2 (Ti3Al)) coated with three coatings: (1) TiAlYN/CrN coating, (2) CrAl with 2%YN addition [1,2] (3) TiAlN with Al2O3 overlayer.
TiAl exhibit numerous attractive properties for high temperature application in the aerospace, industry, power plants and automotive industries.
The poor corrosion is caused by two main factors; first the base alloy Ti45Al8Nb contains relatively low Al amount.
TiAlN + Al2O3 topcoat (DLR coating) Fig. 9, EDX concentration profiles, and SEM image of TiAlN + Al2O3 topcoat (DLR) coated Ti45Al8Nb substrate after 150 hours at 20%NaCl80%Na2SO4 salts mixture (affected region) 0 5 10 15 20 25 30 35 40 45 50 55 60 0 5 10 15 20 25 30 35 40 45 Distance [um] Cocnentartion [at%] at% N at% O at% Na at% Al at% Ti at% Nb at% Cr 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 Distance [um] Concetration [at%] at% O at% Na at% Al at% Ti at% Cr at% Nb 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 0 5 10 15 20 25 30 35 40 45 50 55 60 Distance [um] Concentration [at%] at% N at% O at% Na at% Al at% Ti at% Cr at% NbFigure 9 giving cross - sectional image of TiAlN + Al2O3 topcoat (DLR coating) after 150 hours exposure indicates the spallation of Al2O3 top coat from the sample in certain locations and the formation of non protective
Conclusions  Spraying salt on the samples surface is an effective procedure for testing the hot corrosion behaviour in aggressive environments  Aluminium and titanium oxides scales developed on DLR and Hauzer 1b coatings  Chromium and aluminium thin oxide formed on MUL sample  Cracked Al2O3 top coat on DLR coating allowed to outward diffusion of titanium (Fig . 9)  Formation of TiN at the scale interrupt outward diffusion of titanium in TiAlN + Al2O3 topcoat coating (DLR coating) as Fig. 10 presented  The TiAlYN/CrN coated Ti45Al8Nb and TiAlN + Al2O3 topcoat coated Ti45Al8Nb developed island o of titanium oxide confirmed by surface analysis given in table 2 and 3  Al2O3 oxide top coat on DLR coating has a poor mechanical properties  All samples corroded in edges and rims where platinum suspension wire has been attached References [1] F.

With respect to process control, the heating process is in many cases controlled by giving a predetermined time-power curve without control of the billet condition, which results in poor reproducibility if there are some other disturbing factors.
Flow length + + o - ++ + Typical Defects and Mechanical Properties Along with the semi-solid processing characteristic defects occur in SSM formed steel parts.
An insufficient pressure impact during solidification together with poor feeding properties of the steels causes porosity, either on a micro- or macroscopic scale.
Regarding part properties some basic studies in laboratory scale showed that the mechanical properties of semi solid processed steels could reach similar levels as in forged parts [5,14,15].
[41] Plansee-Group: Products Information Brochure "Material Properties and Applications of Molybdenum", "http://www.plansee.com/hlw/im_materials_ENG_HTML.htm"

In order to verify this critical factor of low density CNTs, the next experiment is made.
The formation of graphene stacks are affected by the carbon source in the deposition.
The modification of carbon nanospheres could make carbon nanotubes possess a lot of new properties, such as enhancement of field emission properties.
Dai, Self-oriented regular arrays of carbon nanotubes and their field emission properties, Science, 283 (1999) 512-514
Zou, Effects of plasma treatment on microstructure and electron field emission properties of screen-printed carbon nanotube films, Physica E, 36 (2007) 28-33

Vibration is the key dynamic properties of the structures [K.
Damage affects the structural dynamic properties in operational conditions.
Non-Destructive Testing is a very good approach for measuring the dynamic properties.
Experimental modal analysis is one of the most basic approaches that can be used to identify structural modal properties from the output-only measurements.
Visual inspection of the signals, time window selection, digital filtering, cross-correlation construction, exponential windowing, and data averaging in time or frequency domain significantly reduce bias and random errors affecting the data quality and improve the reliability of the identified results.

The oxidation rate is reduced by a factor of two over the whole temperature range.
However, different service environments require different design of the operating materials with respect to chemical and mechanical strength.
Micro alloying has proven to be efficient in increasing the service temperature of high temperature steels in that addition of small amount (less than 1%) of certain elements (often rare earth metals or oxides, reactive elements REs) in the metallic matrix imposes increased corrosion resistance without affecting other desired materials characteristics.
When comparing the oxidation rate for coated and uncoated steel, the presence of a coating yields to the decrease of the oxidation rate by approximately a factor of 2.
Another interesting issue that should be investigated in future studies is the effect that silica might have on the thermal cycling properties of the material.

The choice of the method to adopt depends mainly on the following factors: sample size and shape, temperature range and thermal-conductivity range [3].
The moisture effusivity is theoretically based on material properties which are determined under steady state and equilibrium conditions.
Furthermore these types of pore affect the thermal properties
ü Roughness factor [m2/m2] Ratio of the external surface area to the area of the geometrical envelope of the particles.
Allison, a), Analysis of the hygrothermal functional properties of stabilised rammed earth materials.

Compared with the single aluminum flakes, the Al/NiO magnetic composite pigments presented stronger magnetic properties.
Thus the physical properties of the metallic pigments determine the optical properties of the low infrared coating.
Many researches of low infrared coating use a large amount of aluminum flakes in order to reach lower IR emissivity, resulting decrease of mechanical properties of coatings, and more importantly, leading to high lightness (L*) and gloss of the coating [4].
Nickel oxide (NiO) is a green powder which has been of interest due to its magnetic properties [17].
Deng, Optical and magnetic properties of Al/Fe 3 O 4 core–shell low infrared emissivity pigments, J.

The tensile properties of sheets with different thickness and different materials including the plasticity parameters are determined in the first set of experiments.
The sheet metals which constitute tailor-made blanks have different thicknesses and/or material properties and, thus, deform differently.
In order to understand the contribution of the different factors that influence the formability, it is important to isolate each of these effects and study them separately.
Methodology In order to investigate the effects of sheet thickness on the mechanical properties and forming behavior of these two alloys, 2024-T3 and 7075-T6 sheets with four different thicknesses were selected for the study.
Table 1 shows to what extent the tensile properties of the materials change with sheet thickness.

Good optical properties: This paper can also down more than 80% about the usage on visible sunlight and its reflectivity is very low.
An increase in reflectivity is adversely lower the transmittance to affect the image quality.
The transparency of visible light and infrared ray on the transparent substrate is also affected by light reflection, penetration, absorption, scattering and other factors.
The good workability of PMMA sheet has made it easy to be thermo-formed (including mold pressing, blow molding and vacuum forming) in any shapes and mechanical processed such as turning, drilling, cutting and so on.

Due to the nature of gas to liquid phase change, the process, that involves mass and heat transfer at the interface of the vapor, surface, and liquid can be limited by the surface properties.
Therefore, a vast research effort is attracted towards tailoring surfaces physical and chemical properties so that phase change efficiency can be enhanced without the need of any external active means.
DwC can deliver heat transfer coefficients increased by a factor of 2 compared to FwC [15].
Liu, Hydrophobization of epoxy nanocomposite surface with 1H,1H,2H,2H-perfluorooctyltrichlorosilane for superhydrophobic properties, Cent.
Stathopoulos, Influence of organic phase change materials on the physical and mechanical properties of HDPE and PP polymers, RSC Advances 8 (2018) 27438-27447