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Causes of failure of NC machine tool is divided into system fault, artificial fault and gradual fault[1,2]：System fault refers to the fault caused by NC system design, structure and properties of such defects; artificial fault is caused by such as transportation, installation, impact and improper operation and other external factors, the operation skill and habit of operators used to play an important role; In addition to the system fault, the artificial fault, and most of the failure is due to the key components of wear, vibration, such as processing overload or external environmental changes caused by gradual fault[3,4].
For mechanical systems, due to various types of CNC machine tools adopts different mechanical structure, components, according to the characteristics of performance degradation, based on the machine's monitoring system, properly adding sensor, collecting the signal, obtain machining, the fault signal feature real-time data.
Due to special structure and distribution of CNC machine tools, sensors should be installed accurately in place, the wiring should not affect the machine movement.
Zero mean treatment is also called the centralized processing, the mean of vibration signals may produce offset due to the vibration or other factors, with zero mean treatment technology, in order to eliminate vibration interference; by elimination of vibration signal polynomial trend item method, which can eliminate the unfavorable trend signal analysis, to reduce the error of CNC machine fault diagnosis, trend corresponding signal in the frequency domain of the low frequency signal, eliminating the trend is equivalent to a high-pass filtering of signal.
The degradation model by historical vibration data collected for analysis and self-learning, monitoring and prediction on the state of mechanical components.

In addition, UMAT must provide the material Jacobian matrix,, for the mechanical constitutive model.
The most important task in time-dependent analysis procedure was to develop the necessary software to input the creep model and the elastic-plastic properties of concrete through the UMAT user subroutine provided in ABAQUS.
And the computed values were in good agreement with the measured ones and well reflected the time-dependent behavior of the prestressed concrete beams. [20] Time-dependent Finite Element Parametric Analysis Various factors affect the long-term behavior of prestressed concrete beams, including load factors and non-load factors.
A time-dependent finite element parametric study was performed to investigate how the factors influenced the long-term deformation of prestressed concrete beams.
Cao, et al, Long-term Deformation of Prestressed Concrete Beams with Ballastless Track and Its Influencing Factors, Journal of Central South University (Science and Technology), 42,6(2011), 1756-1763

Due to the fixation of the deformation axis, it is possible to calculate the value of Schmid factor for each twinning system.
The obtained values of Schmid factor for active systems (solid lines) and inactive systems (dashed lines) are shown in Figure 5a.
Austenitic steel (Germany: LAP LAMBER Academic Publishing) p 148 [7] Kozlov E V, Popova N A, Kabanina O V, Klimashin S I and Gromov V.E. 2007 Evolution of phase composition, defect structure, internal stresses and redistribution of carbon at temper of cast structural steel (Novokuznetsk: SibGIU Publ) p 177 [8] Gagauz V P, Kozlov E V, Danilov V I, Ivanov Y F and Gromov V E 2008 Structural-phase states and mechanical properties of thick welded joints (Novokuznetsk.
Fizika Moscow 25 №8 3-14 [19] Zeeger A 1960 Dislocations and mecjanical properties of crystals (Moscow.
Structure and mechanical properties of metals (Moscow.

Chatter Mathematical Model Various factors are the source of vibration during milling.
Improved structural damping of small diameter end mills [3], passive linear shock absorbers embedded in the machine spindle [4], adjustable vibration absorbers installed on the cantilever plate [5], [6], additional mass elements that improve the dynamic properties of the workpiece [7], also help to reduce the vibration amplitude during milling.
Active methods of vibration reduction affect the source of disturbance, changing the magnitude or nature of the force loading of the elements of the technological system.
The physical essence of the mathematical model of the amplitude of forced vibrations during cylindrical milling is the sum of harmonic vibrations with different amplitudes at frequencies that are multiples of the frequency of the fundamental (first) harmonic, i.e. expression (1) can be represented as (2): (2) where Аi is the amplitude of the i-th harmonic of excitation; kdi - dynamic factor; φi is the phase of the i-th harmonic of excitation.
Meng, Chatter mitigation for the milling of thin-walled workpiece, International Journal of Mechanical Sciences. 138 (2018) 262-271

Those measuring results can be used to analyze the influence factors of welding deformation, control the welding deformation and verify the welding numerical simulation.
Introduction With the advantages of light weight, excellent processing property (easy processing and forming) and the convenient connection, sheet metal is widely used in manufacturing industry such as marine engineering, aeronautics and astronautics devices, automobile industry, and so on.
But the optical circuits are complex and are susceptible to environmental factors to environmental impacts.
In the process of welding, the image quality may be affected by a large amount of smoke and the white brightness.
In heat-affected zone, with the influence of the tensile stress produced by cooling of the weld bead and the plate in heat affected zone is heated, sheet metal in this area has a certain expansion in the transverse direction, leading to the value of the transverse strain in the heat affected zone are positive.

Marchetto et al. have proved that when two surface sliding, the phonon in the form of mechanical waves transmitting along the surface formed the physical resistance of the interface sliding [4].
In addition, there are many factors which affect the friction on micro and nano scale.
The results indicate that the normal load affects the friction behavior on the micro scale, and also reveal that under high load, the micro friction could change to the macro friction.
Marchetto et al., AFM investigation of tribological properties of nano-patterned silicon surface, J.
[17] Yifang Cao et al., Nanoindentation Measurements of The Mechanical Properties of Polycrystalline Au and Ag Thin Films on Silicon Substrates: Effects of Grain Size and Film Thickness, J.

(2) Dep. of Aerospace and Mechanical Engineering, University of Notre Dame, USA
Illustration of the three-layered polymer-coated steel used in the experiments There is significant flexibility in formulating this material, and many combinations of chemical and mechanical properties can be achieved.
The Surface Quality Factor has been defined as: 0.
Representative examples of these Surface Quality Factors are given in Fig. 2.
The inserts were produced by diamond polishing, but were not refinished for the subject research in order to save time and expenses; it is felt that surface quality factors of 8 could probably be improved with better tool surface finish.

Introduction H-beam section economic and reasonable, superior mechanical properties, manufacture and installation process is simple, convenient, fast, etc, are widely used the areas of national economic construction, especially in the heavy industry workshop, is often used as a bearing beam and column frame structure.
Bearing capacity coefficient and the relationship between the axial compression ratio is influenced by some factors, for the paper specifications and boundary conditions of specimen, is obtained by fitting the solid residual bearing capacity coefficient of simply supported specimens and axial compression ratio of a function of n.
Bearing capacity coefficient and the relationship between the impact energy is affected by some factors, for the paper specifications and boundary conditions of specimen, is obtained by fitting the solid residual bearing capacity coefficient of simply supported specimens and a function of impact energy.
Compared with existing experimental results, the finite element model can well simulate h-beam in drop hammer impact on the mechanical performance and axial Compression test (3)Impact on axial force of artifacts - coupling under the axial compression ratio and impact energy on the bearing capacity of the residual effect are analyzed.
Journal of mechanical design and research, 2001, (4)

It reflects mutual influence of process factors on the elastic medium contact pressure value for the rotary method of medium action on the parent sheet.
Using the obtained equation, the diagrams of experimental distribution of contact pressure for optimum values of process factors were plotted by calculation and experiments, and they were graphically compared with similar diagrams obtained by means of numerical investigations.
The optimum combination of design and process factors (punch curvature, relative dimensions of elastic diaphragm, degree of its upset distance, etc.) was determined.
These factors ensure the achievement of expedient width of the uniform elastic medium pressure zone (40 to 50 mm) and the level of operating pressure in it (100 to 140 MPa), sufficient for implementation of separating process.
Such diagrams enable estimating the possibility of performing separating operations by rotary action of a tool on the parent sheet during die cutting of parts with various geometric shapes, a wide range of thickness values and mechanical properties of materials.

It refers to a technological materials property, not an intrinsic one.
Some factors affecting the rate of grain growth in metals.
Doctoral Thesis, Faculty de Mechanical Engineering of UNICAMP, Campinas.
Machining Strength of Materials – Concept, Measurement, and Applications of a New Property.
Influence of crystallographic textures on tensile properties of 316L autenitic stainless steel.