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Then, the procedures of lifetime prediction in real applications are addressed, which include power loss calculations based on the actual mission profile, the conversion of power loss profile to temperature profile according to the module's thermal properties, the temperature cycles counting by Rainflow algorithm, and lifetime calculation by the fatigue linear accumulation damage theory.
Then, the temperature profile of a module in running is derived based on the module’s thermal properties.
Reliability and Lifetime Assessment Tests In the application, power modules are exposed to both passive temperature swings due to environmental factors and active temperature cycles generated by power consumption in operation.
Therefore, factors such as wire bonds dimension, current, silicon thickness were taken into account in reliability analysis and lifetime modeling.
Feller, Model of power cycling lifetime of IGBT Modules - Various Factors Influencing lifetime, Integrated Power Systems (CIPS), Mar. 2008

So far, porous phenolic composites are receiving more and more attention in the aerospace, defense and the high-tech fields due to their lower density, high damping property and electromagnetic shielding ability, etc.
In fact, damage at any instant exercises a significant influence on the mechanical properties of materials.
Before the appearance of macro-level fracture, the microscopic damage already affects the material stress and strain relationship especially near the crack tip.
Suppose that there are m voids in material at time t, let denote the nucleation density (the number of newly-increased void due to nucleation in unit volume of solid per unit time) and be the void volume at the minimum nucleation, one can obtain the following expression of : (6) By assuming the inertia effects are negligible, the growth rate of void can be obtained based on the phenomenological point of view, i.e., [5]: (7) where is the characteristic factor of void growth, denotes the tensile stress, is the threshold stress at damage, andis a damage dependent exponent.
Spall simulation for porous phenolic composites Research studies have shown that phenolic composites exhibit some special properties as stated above.

The research on molten salt’s thermophysical properties are mainly discussed in this paper.
Xiong, Deterioration Factors of Heat Transfer Fluids and Its Preventive Measures, Synthetic Lubricants. (2011) 25-27
Wei, et al., The preparation and properties of multi-component molten salts, Applied Energy. 87 (2010) 2812-2817
Wu, et al., Dynamic Measurement of Thermophysical Properties of Molten Salt and Error Correction Method, CIESC Journal. (2012) 2341-2347
Makled, et al., Thermal and mechanical properties of Sn-Zn-Bi lead-free solder alloys, Journal of Alloys and Compounds. 484 (2009) 134-142

The construction of the houses does not satisfy the requirements for seismic resistance into consideration, tend to be small earthquakes can cause of structural damage and affect the normal use function.
HPFL has excellent physical and mechanical performance, durability and corrosion resistance and other characteristics, the reinforcement is very suitable for civil engineering area.
An excellent property of HPFL is low shrinkage
At the same time, the strength of cement mortar is also affecting the destruction as another factor.
Its construction is simple, can be used in outdoor reinforcement structure without affecting the indoor furniture and wall decoration.

-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.

Introduction The role of microstructure in affecting fatigue behavior of titanium (Ti) alloys has been recognized for many years.
Continuous cycling fatigue life also is affected by the type and degree of microtexture.
Both factors contribute to the dissipation of plastic work during fracture and the resulting morphology on the fracture surface.
In this paper we describe the current understanding of fatigue crack initiation and the early stages of growth in α+β Ti alloys as affected by microtexture.
Such a sharp microstructural discontinuity is accompanied by a commensurate change in mechanical properties in the base metal and process zone.

., because they have the desired mechanical property and the flexibility to be processed into different modules [2-4].
Moreover, the mixed matrix properties are affected by filler pore size, particle size, loading of filler and polymer properties. [13].
This study demonstrated that the incorporation of 30 wt. % CMS as inorganic filler in PES dope solution increased the permeance of CO2 and selectivity of CO2/CH4 by a factor of 2.3 and 2.2, respectively.

On the other hand, SiC is a candidate semiconductor for high-power electronic devices owing to its wide band-gap and other intrinsic properties [3].
The bonding temperature affects the interfacial structure.
The frequency factor of the growth rate (k0) and the apparent activation energy for growth (Q) of the TiC/(TiC+Ti2AlC) layers are deduced as 4.3×10-4 m2s-1 and 370 kJmol -1, respectively, while those of the Ti5Si3CX+Ti2AlC layer are 4.8×10 -7 m 2s -1 and 250 kJmol -1, respectively.
Thus, the growth rates of the reaction products are sensitively influenced by the bonding temperature, while the apparent interfacial phase sequence is not affected in the major part but only in the state of the TiAl2.
The values of pre-exponential factor for the growth rate and the apparent activation energy for the growth of the carbide layers are 4.3×10-4 m 2s-1 and 370 kJmol -1, respectively, while those of the Ti5Si3CX layer are 4.8×10-7 m2s -1 and 250 kJmol -1, respectively.

In the studies of the microstructure and properties, the researchers [12-13] established the relationship of foam material, production process and preparation of the alloy with graphite morphology.
Fig. 5 Typical cooling curve and first derivative curve TE’—Stable (graphite) eutectic equilibrium temperature TE—Metastable (carbide) eutectic equilibrium temperature Tmax—Maximum Temperature of cooling curve TAL—Liquid temperature of austenitic precipitation TES—Temperature of start of eutectic freezing TEU—Lowest eutectic temperature TER—Highest eutectic temperature TEN—Temperature of the end of solidification tL— Interval period of cooling between Tmax and TAL tRE—Interval period of cooling between TALand TES tE—Time of eutectic freezing TE—Eutectic degree of undercooling of grey cast iron, (TE- TEU) The law of cooling features at different solidification stage and corresponding influential factors could be revealed by using thermal analysis method.
Fig. 7 Temperature of primary austenite formation From the analysis of the data, critical temperature of the primary austenite formation had no significantly affected by inoculation condition and casting methods, and is determined by the composition of grey cast iron.
(4) The interval period of eutectic solidification is mainly influence by the wall thickness and slightly affected by types of casting methods and cast iron condition.
American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED, 2000, 255: 79~84 [5] Li Fengjun, Shen Houfa, Liu Baicheng.

Acid resistance is one of the important factors which affect the permeability, fracture conductivity and bearing time of the fracturing proppants, and further affect the productivity of the wells [8-9].
THE CHEMICAL COMPOSITION AND RELATED ROPERTIES OF THE SAMPLES Samples No Chemical composition (wt%) properties Sintering temperature (oC) Al2O3 BaCO3 Bulk density (g/cm3 ) Water bsorption (%) Acid solubility (%) 1 40 60 2.53 7.60 4.86 1600 2 80 20 2.74 2.17 1.35 1600 3 85 15 3.11 1.60 0.84 1600 4 90 10 3.26 1.13 0.52 1600 5 100 0 3.55 0.20 1.47 1600 sintered for 2 h with a heating rate of 5 oC/min and cooled in electrical furnace.
[24] Guohua Chen, Dechao Niu, “Mechanical activation of barium aluminate formation from BaCO3–Al2O3 mixtures,” J.