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SCBT0.3 + Mn x wt% lead-free ceramics showed an extremely high mechanical quality factor (Qm) of more than 3000 in the (33) vibration mode under small-amplitude vibration.
Table I shows the piezoelectric properties under small-amplitude vibration for SCBT0.3-based ceramics poled at 200ºC.
Thus, piezoelectric properties at large-amplitude driving cannot be considered from those at small-amplitude driving.
Figure 5 and Table II show the P-E hysteresis loops and polarization properties of SCBT0.3 + Mn x wt% ceramics.
Table I Electrical and piezoelectric properties of SCBT0.3 + Mn x wt% ceramics under small- amplitude vibration.

And the effects of workpiece speed, ultrasonic amplitude and grain size on surface roughness were researched by using single-factor testing way.
Introduction Titanium alloy is widely used in various fields because of its fine physicochemical properties.
However, surface roughness, which is one of the important indexes in surface processing quality, is a key factor for fatigue strength, contact stiffness, corrosion properties and complexation properties [2].
The effects of workpiece speed, ultrasonic amplitude and grain size on surface roughness are researched by using single-factor testing way.
Fig. 2 Effect of workpiece speed on surface roughness (amplitude: A=12μm) According to the Fig. 2, we can know that the surface roughness does not change significantly with the increasing of workpiece speed in common lapping whether using W28 grinding paste or W7 grinding paste, the reason is that the increasing of workpiece speed is essentially that time variable is introduced to material deformation removal process, therefore the changes of workpiece speed mainly affect the physical and mechanical properties of machined surface[4], however, it exercises a very little influence on the geometric properties [5].

Moisture severely affects aerospace structures and offshore platforms during their service life span.
Composite materials allow moisture to be absorbed through the environment, which severely affect the structural integrity of structures [3,4].
The reduction in mechanical properties is often due to degradation at matrix/fiber interface [7,8].
Hahn, AFM characterization of the interfacial properties of carbon fiber reinforced polymer composites subjected to hygrothermal treatments, Compos.
Jiang, Surface and interface properties of carbon fiber composites under cyclical aging, Appl.

Especially wheel profile is one of the most important design factors to rule the running stability and safety of train.
However, roughness on the surface, humidity and such fine particles as rain, snow and sand are also affecting.
The mechanical property of ER7 is shown on Table 1.
The figure of Korean High-Speed Railway is UIC60 and its mechanical property is listed on KSR TR001-07 (Korean Railway Standards).
Table 1 Mechanical properties of wheel for KTX Steel Grade Rim Tensile Strength (N/㎟) Yield Strength (N/㎟) Reduction of section area(%) Brinell hardness Impact values KU at +20℃ : Aver.

Besides, it analyzes the advantages and the necessities of the natural fibre nonwoven materials applied for the noise control, illustrates the present research status and the factors that introduces the sound absorption properties of the natural fibre nonwoven composites used for noise reduction.
Factors that affect the absorption A number of numerical and experimental methods relevant to sound absorption behavior of nonwoven materials have been reported in the literature.
The absorption properties are also affect by the compression of a fibrous mat[21], Insulation and absorption properties of nonwoven fabrics depend on fiber geometry and fiber arrangement within the fabric structure.
The experiment showed that the higher the total fiber surface area, the greater possibilities for a sound wave to interact with the fibers in the fabric structure. what,s more, the surface characteristics, sample size and air gap behind the sample affect the acoustical properties as well[22]. viscoelastic property is found to be the related to the sound absorption property of fabric. the plasma treatment on nonwoven fabrics changes their sound absorption and viscoelastic property as well as their fabric weight and pore size[23].
Wong, Mechanical Management and Development, Vol.23, No.2, 1-3, 2008, (In Chinese) [10] X.W.

Analyses of substrate negative bias voltage on morphology thickness of the film, bonding strength and micro hardness and other properties.
Introduction In multi-arc ion plating, the morphology, composition, thickness, etc. will change with different process parameters on the film, and then affecting the performance of the film.
Substrate negative bias is one of the important factors in the coating process.
The effect of substrate negative bias on the morphology and microstructure composition and properties of multilayer composite films was studied on this paper.
There are two major factors for the increase of adhesion.

The addition of nano-silica particles in polymer cement concretes and mortars affects both fresh and hardened state properties.
The percentages shown in Table 1 are the best resulting mixes made of each colloid, considering mechanical properties (compressive and flexural strength) and permeability properties (capillary absorption rate).
Mechanical properties tests.
Mechanical properties.
Ozkul, The effect of colloidal nano-silica as a cementitious material, on durability and mechanical properties of mortar, In: 11th Int.

The research results of electron microscopic studies were the base for demonstrating formation of the hydraulic phase at the grain boundary of sintered beryllium and influence of the reinforcing phase on the mechanical properties of the HIP blank.
It is also known that Beryllium strength properties including the precision elastic limit increase when content of hardening phases increase along grain boundaries, primarily Beryllium oxide [2-5].
However, the strength properties of the blanks depend on both the average grain size and the temperature of isostatic pressing (Figure 3).
Determined graphical and analytical dependences provide the possibility of “fine” control of the Beryllium strength properties by “dosing” the contribution of each element of the “dispersion-grain-boundary” hardening mechanism.
The effect of grain boundary oxide inclusions on the mechanical properties of hot-pressed beryllium.

By theoretic research and simulation, main factors for finishing effect and uniformity are analyzed.
Consequently, it has effects of finishing crankshafts, increasing surface quality and improving the physical-mechanical properties [1-5].
At the same time, the degree, particles is driven to rotate, is relatively weakened, thus affecting finishing effects and efficiency.
The depth of crankshafts in machining medium is an important factor.
Conclusions Through theoretic analysis, S, f and n are main factors of affecting finishing effect and efficiency.

In the Table 2 mechanical properties according the EN 10028-2 standard and from testing in this investigation are presented.
A chemical composition of the electrodes was determined by Optical Emission Spectroscopy (OES) and mechanical properties were obtained from literature [6].
The mechanical properties of the Ni base austenite electrode overmatching properties of the parent metal.
Mechanical properties, as tensile testing properties of the samples with parallel and concave sides, energies absorbed, bend testing properties and hardness of the all welded joints were investigated.
Mechanical properties of the welded joints Tensile properties.