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Piezoelectric properties of materials (e.g.
A rapid decrease in piezoelectric properties of silicon (SiO2) is observed at a temperature of 523 K while at 846 K the piezoelectric properties disappear.
A variety of factors have an influence on both the measurement system and the object being measured, and thus on the measurement results uncertainty.
It was assumed that the following factors affected the uncertainty of the obtained results: errors from the piezoelectric transducers, error from the charge amplifier, and error from the A/D KPCI-3110 transducer.
Dekys, et al., Understanding of the dynamical properties of machines based on the interpretation of spectral measurements and FRP, Applied Mechanics and Materials 486 (2014), 1660-9336

These properties make them good candidates as polymer electrolyte membranes for direct methanol fuel cell application.
For this purpose, PVA is a possible candidate because of its good chemical stability, film forming ability and high hydrophilicity and availability of crosslinking sites to create a stable membrane with good mechanical properties and selective permeability to water.
Table 1 Composition and properties of PVA/PMA composite membranes Membrane PMA (Wt %) Crosslink density (mol %) Thickness (µm) Conductivity (Scm -1) Diff.
j = jo exp (-Ea/RT) = A/T exp (-Ea/RT) where jo and A are pre-exponential factors and Ea the activation energy.
Further the flexible nature of this membrane with high conductivity, low methanol permeability, good thermal stability and mechanical properties, is highly expected as a promising proton conductive membrane for DMFC application.

Microstructure and Mechanical Properties of fly ash/Al-25Mg Composites Processed by Powder Metallurgy Method Qingping Wang 1, 2, a, Yucheng Wu 1, b, Fanfei Min 2, c 1 School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China 2 School of Materials Science and Engineering, Anhui University of Science and Technology, Huainan 232001, China aqpwang@aust.edu.cn, bycwu@hfut.edu.cn, cffmin@aust.edu.cn Keywords：fly ash; aluminum matrix composite; friction and wear; wear mechanism.
They detected the property of this material, assessed its property and studied its probable prospect of application in components of machine.
When the fly ash is more than 10%, it will become glomerate severely and the consistency of the composite will decrease, and these factors affect the property of the composite.The hardness of the composite increases greatly with the increasing of fly ash in the composite.
Test load influences the property of friction and wear by the size of contact area and the degree of distortion.
So, the wearing property of fly ash particle/Al-25% composite will increase with the increasing of fly ash.

Properties of several cement compositions are examined and compared to properties of β-tricalcium phosphate and calcium dihydrogen phosphate monohydrate based cements.
This suggests that paste liquid affects the reaction between tricalcium phosphates and MCPM.
This indicates possible differences in the course of cementing reaction, and might be one of the factors contributing to differences in might contribute to differences in compressive strength of cement samples.
Tagami, Properties of injectable apatite-forming premixed cements, J.
Berzina-Cimdina, Setting properties of brushite and hydroxyapatite compound cements, Adv.

Thus, co-extrusion can be used to improve the functional properties of composite materials, with or without a concurrent boost of its intrinsic properties.
In order to overcome this, the properties of different regions of the material structure can be modified in order to create alternate crack paths which are more easily followed.
To accomplish this, different materials with the right combination of properties for a given application can be engineered in the desired locations on a macroscale.
While many factors can play a role, the two main contributors to the development of interfacial cracks are the differential sintering of the two materials as well as their differing thermal expansion coefficients.
This allows the functional properties of a composite to be tailored by selecting and combining materials with desired intrinsic properties and arranging them in a desired architecture.

Because of these factors, the foamed cement composites become less homogenous and its component cohesion making it weaker.
However, Class F fly ash is more widely use in the manufacturing of fly ash concrete in industry, due to one of its properties that able to create concrete with higher ultimate strength compare to Class C fly ash.
After polystyrene beads had been decomposed, it left quite a lot of hollow cells all around the structure that looks similar to the honeycomb structure, these hollow cells shaped structure provide the cement composite with minimal density and relative high out-of-plane compression properties and out- of-plane shear properties [5, 6].
Mechanical properties of cement foams in shear.
The effect of foam polystyrene granules on cement composite properties.

Experimental results Variation of Material Properties with Aging Time.
Figures 2~3 show that the yield strength and fracture properties also decreased with aging time.
Generally, corrosion resistance and strength can be affected by these precipitations.
Our conclusion could be stated as follows: (1) The yield strength, tensile strength and fracture properties of aged CF-8A stainless steel decreased with aging time up
The decrease in strength and fracture toughness was considered to be the influence of the factors such as chromium precipitation at the austenite-ferrite boundaries, sulfur precipitation and accelerated aging conditions

The paper deals with some major factors which influence material removal rate under constant pressure grinding method, such as abrasive type, belt speed, the normal grinding force, type of grinding fluid, with 3 different kinds of abrasive belt.
Test materials use 1Cr13 stainless steel, which’s sample size is 28mm × 300mm, and its main chemical composition and mechanical property are shown in Table 1.
Repeat experiment 5 times and observe the average in order to eliminate the effect of random factors and improve the reliability of the results.
Table 1 Chemical composition and mechanical property of 1Cr13 stainless steel chemical composition wt% C 0.23 Mn 0.53 P 0.021 S 0.015 Si 0.54 Ni 0.15 Cr 12.77 mechanical properties σb[MP] 758 Δ[%] 22.5 Ψ[%] 65 HB 22.5 αk[J·cm-2] 175 Λ[W/m·K] 24.2(100ºC) Results and Discussions Effect of Belt Speed on Material Removal Rate.
Conclusion The material removal rate is significantly affected by abrasive types.

Fan(2012) used the correction factor method of damage extent based on strain energy, identified and diagnosed damage of plate structure.
(2) the ultrasonic testing technology based on pulse echo method uses the properties that wave can reflect when meeting different medium to detect, due to wave attenuation properties differs in different materials, and the method has high sensitivity, low cost, and high efficiency
But due to the existence of such factors that the dynamic characteristics can be measured by the model error, measurement noise and civil engineering structure are not sensitive to the local stiffness change, the method is limited in practical application.
A strain energy-based damage severity correction factor method for damage identification in plate-type structures[J].
Mechanical Systems and Signal Processing, 2012, 28: 660–678.

However, unlike mechanical fastening welding would lead to a changed microstructure with a softened fusion zone and an adjacent heat-affected zone (HAZ).
All these factors will have a profound influence on the fatigue life of a welded structure compared to fastened one.
These factors are necessary for the damage-tolerant design necessary for safety-critical structural members in civil aviation.
The composition and mechanical properties are shown in table 1.
- 2 - Cu [wt%] Mg [wt%] Zn [wt%] Mn [wt%] Cr [wt%] Si [wt%] Fe [wt%] UTS [MPa] 0.2% PS [MPa] Elongation [%- On GL =25] 3.7- 4.5 1.2- 1.5 <0.25 0.15- 0.80 < 0.10 < 0.15 < 0.20 470 360 20 Table 1: Chemical composition & mechanical properties of AA2024- (the alloying elements are shown in the table; the balance is aluminium) The VPPA welding process was applied to weld two plates of the alloy of dimension 400 × 140 × 12.5 mm3.