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Make use of FPGA to carry out ultrasonic wave high definition Nondestructive Thickness Measurement Yang Weijian Sichuan University of Science & Engineering, Sichuan Zigong,643000 Keywords: Nondestructive Thickness Measurement, Ultrasonic, MCU, FPGA, Transmission Speed Abstract.This paper discussed the principle of the Nondestructive Thickness Measurement creation of the ultrasonic wave high definition and analyzed the reason that the ultrasonic wave measures a thick accuracy decision factor and error creation.
Their physical properties and principles of its particularity, in some instances play an important function, and complementary to conventional methods, ultrasonic non-destructive high-precision measuring technique is one of them.
The principle of ultrasonic non-destructive thickness measurement and work characteristics Ultrasound is a mechanical wave frequencies above 20000Hz, due to high frequency ultrasound, wave length, direction and therefore has good penetration, and because the ultrasonic energy, to facilitate detection, it can be used to achieve non-destructive testing.
Error of ultrasonic wave velocity.Ultrasonic propagation velocity affected by the test material, the different propagation velocity of ultrasonic testing of different materials, at the same time have a close relationship with the temperature.
Using Quartus II 6.0 is designed as follows: The internal PLL design.By calculating the internal PLL output is 240MHZ, the external clock input is 48MHZ, so set the multiplier factor of 5 / 1, to provide internal clock C0 output.

Cross sectional area of single filaments, a key parameter to characterize fiber properties, was experimentally studied using a desktop scanning electron microscope.
Introduction Precise measurement of cross sectional area of fiber samples is one of the important tasks in characterizing mechanical properties such as tensile strength and modulus[1-4], and electrical properties such as resistivity[2, 5, 6] for fiber materials.
(COV~5%) SDM High Affected little by the angle to electron beam.
(COV<1.6%) ADM Low Affected substantially by the angle to electron beam.
[15] "ASTM D4018 - 11 Standard Test Methods for Properties of Continuous Filament Carbon and Graphite Fiber Tows", 2011

The casualties and property losses of accidents caused by fatigue failure are very great [1].
It gets extensive attention among some famous foreign enterprise groups, and it plays a tremendous role in mechanical products development and design, which produces remarkable economic benefits.
The change in load order will not affect the resistance to fatigue life.
Input stress value of balance beam, time curve of variable amplitude load and material fatigue properties into MSC.FATIGUE, then get the damnify and fatigue life of balance beam as is shown in Fig. 8.
[2] Zhou, C.N., Xie, J.J. and Hong, Y.S: submitted to Mechanical Strength (2004), In Chinese

This is especially true for rotor craft, where weight is a critical design factor [10].
At the boundary of the nugget zone there was the thermomechanical affected zone (TMAZ), see figure 6 b.
To enhance the precision of the numerical model, a layered type of element needs to be used, even if the assignment of the material properties among different layers is not trivial.
Prisco, Experimental evaluation of properties of cross-linked polyethylene Mater.
Khraisheh, Mechanical characteristics of superplastic deformation of AZ31Magnesium alloy J.

Consequently, these morphological changes affect primarily the thermal conductivity and eventually the Young' Modulus which are the key physical properties of this material group.
The required properties for TBCs are low thermal conductivity, high thermal expansion coefficient, thermal shock resistance, as well as phase and morphology stability under long-term and high temperature service conditions.
Thermo mechanical tests of these TBCs revealed significant property changes due to their limited phase and microstructure stability and low sintering resistance [3,4].
For these systems at least two factors contribute to a reduced thermal conductivity: firstly, thin films have been reported to exhibit lower thermal conductivities than the respective bulk materials, and secondly, additional boundaries are incorporated perpendicularly aligned to the heat flux.
High temperature ageing changes thermal and mechanical properties of TBCs.

Sharma et al. [9] investigated the effect of graphite content on wear properties of ZA-27 alloy and concluded that the graphite content up to 1-5% increases the wear resistance property of the composite.
Further, the work also aims at evaluating the wear properties of composites at varying loads and speeds.
This is obviously due to the lubricating properties of graphite.
Satish: Mechanical properties and fractography of zircon-particle-reinforced ZA-27 alloy composite materials.
Auradi, Madeva Nagaral, Bharath V: Effect of Al2O3 particles on mechanical and wear properties of Al6061 alloy metal matrix composites.

Damage mechanics researches the mechanical behavior of single cracks and even more importantly the macro mechanical behavior of overlapped cracks.
The properties of the molding sand are shown in Table 1.
The maximum tensile stress occurred somewhere away from the center of the jet to a distance that depends on several factors.
This indicates that the attacking time of the water jet is only one of the factors which influence the removal effect of the molding sand.
Which might be affected the numerical results accurately.

The productivity is possible to measure by various indicators including evaluation by some factors (see the next section), by which is possible to impact their level.
It is affected by many factors.
To these factors belong length of service in the branch, relationship to the enterprise, work environment, abilities of worker or quality of findings.
§ Productivity of assembling is possible positively to affect by formation of store zones.
ICIL 2014, Faculty of Mechanical Engineering and Naval Architecture, 2014: pp. 176-180

Tensile properties were evaluated with universal testing machine (Hounsfield, H1000KS).
Mechanical properties of PLA resins (NatureWorks) Grade PDI*** Tensile strength (MPa) Elongation at break (%) Young’s modulus (GPa) PLA 6201D 1.5 61.1 ± 5.2 2.10±0.10 3.65±0.09 PLA 4032D 1.6 64.1 ± 2.3 2.23±0.00 3.38±0.21 ***PDI means polydispersity index.
Tensile properties were measured with film specimens.
Mechanical Properties of PLA Blend In Fig. 4, tensile strength of PLA 4032D/PBAT blends decreased with increase of PBAT content.
This means the additive content is a kind of important factor to affect and control the bio-degradability of green geosnthetics.

The transient temperatures generated by grinding and the heat flux produced at the wheel workpiece-interface, are the major factor, which influence surface integrity and phase transformation on the machined surface [2, 3].
In order to simplify the simulation, a 2D FE model is chosen with temperature-dependant thermal material properties for the grinding of high speed steel workpiece.
The involved expansion of the very small heat affected volume of material surrounded by cold material, assumed as rigid, leads to compressive stresses.
A thermo mechanical finite element model shows that residual stresses decrease beneath the surface and it is found out that there is a significant relation between temperature and residual stress.
The next step is to verify the model experimentally .A metallurgical thermo-mechanical finite element will be conducted in order to understand microstructure changes of the high speed steel material and its effects on the presence and the nature of residual stress in the workpiece.