Effect of substrate deformation on the microcantilever beam-bending test

2000 ◽  
Vol 15 (9) ◽  
pp. 1868-1871 ◽  
Author(s):  
Tong-Yi Zhang ◽  
Ming-Hao Zhao ◽  
Cai-Fu Qian
Keyword(s):  
Analytic Formula ◽  
Bending Test ◽  
Proportionality Factor ◽  
Third Order ◽  
Element Analysis ◽  
Order Polynomial ◽  
Beam Thickness ◽  
Beam Bending ◽  
Microcantilever Beam ◽  
Fixed Beam

With regard to substrate deformation, this work analyzed the microcantilever beam-bending test and provided a closed formula of deflection versus load. The substrate deformation was formulated using two coupled springs; the spring compliances were related to the elastic compliances of the substrate, the support angle between the substrate and the microcantilever beam, and the beam thickness. Finite element analysis was conducted to calculate the spring compliances and verify the analytic formula. The results showed that the proportionality factor of the load to the deflection was a third-order polynomial of the length from the loading point to the fixed beam end. Examples are also given to indicate the relative error of Young's modulus when evaluated with the beam-bending theory without considering the substrate deformation.

Thermal Error Modeling of Precision Positioning Stage

2013 ◽  
Vol 694-697 ◽  
pp. 767-770
Author(s):  
Jing Shu Wang ◽  
Ming Chi Feng
Keyword(s):  
Thermal Deformation ◽  
Thermal Error ◽  
Error Modeling ◽  
Precision Positioning ◽  
Third Order ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Positioning Stage ◽  
Order Polynomial ◽  
The Relationship

As the thermal deformation significantly impacts the accuracy of precision positioning stage, it is necessary to realize the thermal error. The thermal deformation of the positioning stage is simulated by the finite element analysis. The relationship between the temperature variation and thermal error is fitted third-order polynomial function whose parameters are determined by genetic algorithm neural network (GANN). The operators of the GANN are optimized through a parametric study. The results show that the model can describe the relationship between the temperature and thermal deformation well.

Research on Deforming Law of Beam Structure

2011 ◽  
Vol 101-102 ◽  
pp. 1114-1118
Author(s):  
Feng Xu
Keyword(s):  
Concrete Beam ◽  
Plain Concrete ◽  
Bending Test ◽  
Damage Effect ◽  
Analysis Software ◽  
Beam Structure ◽  
Element Analysis ◽  
New Methods ◽  
Concrete Damage ◽  
Beam Bending

The equations of damage evolution of cross-section and the deflection deformation of concrete beam were established. Through the plain concrete beam bending test, the formula for calculating the deflection was verified. It is proved that the formula established in this paper is more accurate than the equation that doesn’t consider the damage effect. The concrete beam was modelled and analyzed by means of finite element analysis software, and comparison was carried out between the numerical simulation result and the experimental data. On the basis, new methods and ideas about concrete-damage were proposed.

Static Analysis of Thin Film Piezoelectric Micro-Accelerometer Using Analytical and Finite Element Modeling

2003 ◽  
Author(s):  
Zhaochun Yang ◽  
Qing-Ming Wang ◽  
Patrick Smolinski ◽  
Hongbo Yang
Keyword(s):  
Finite Element ◽  
High Sensitivity ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Beam Thickness ◽  
Input Acceleration ◽  
On Chip ◽  
Micro Accelerometer ◽  
Fixed Beam ◽  
Good Agreement

On-chip microaccelerometers using piezoelectric thin films has attracted much interest due to their simple structure and potentially high sensitivity. However, the relationships between the structure of the microaccelerometer and its performance still need to be further developed in more details. In this paper we present a theoretical model for a microaccelerometer with four suspended flexural PZT/silicon beams and a central proof mass configuration. The model takes into account the effect of device geometry and elastic properties of the piezoelectric film, and is supported by the finite element analysis. The good agreement of the results demonstrates the validity of the modeling assumptions. This study shows that the accelerometer sensitivity decreases with increasing the width and thickness of the bilayer beams, and elastic modulus of the mechanical microstructure, while increasing the length of the beam, increases sensitivity. For a fixed beam thickness, a maximum sensitivity exists for appropriate PZT/Si thickness. In addition, it is found that the sensitivity is also proportional to the magnitude of the input acceleration. The results of this study can be readily applied to for on-chip piezoelectric microaccelerometer design and its structural optimization.

Exact Perturbation for the Vibration of Almost Annular or Circular Plates

1995 ◽  
Author(s):  
R. G. Parker ◽  
C. D. Mote
Keyword(s):  
Circular Domain ◽  
Circular Plates ◽  
Irregular Domain ◽  
Third Order ◽  
Element Analysis ◽  
Shape Deviation ◽  
Arbitrary Boundary ◽  
Boundary Shape ◽  
Circular Domains ◽  
And Control

Abstract Using perturbation analysis, the eigensolutions for plate vibration problems on nearly annular or circular domains are determined. The irregular domain eigensolutions are calculated as perturbations of the corresponding annular or circular domain eigensolutions. These perturbations are determined exactly. The simplicity of these exact solutions allows the perturbation to be carried through third order for distinct unperturbed eigenvalues and through second order for degenerate unperturbed eigenvalues. Furthermore, this simplicity allows the resulting orthonormalized eigenfunctions to be readily incorporated into response, system identification, and control analyses. The clamped, nearly circular plate is studied in detail, and the exact eigensolution perturbations are derived for an arbitrary boundary shape deviation. Rules governing the splitting of degenerate unperturbed eigenvalues at both first and second orders of perturbation are presented. These rules, which apply for arbitrary shape deviation, generalize those obtained in previous works where specific, discrete asymmetries and first order splitting are examined. The eigensolution perturbations and splitting rules reduce to simple, algebraic formulae in the Fourier coefficients of the boundary shape asymmetry. Elliptical plate eigensolutions are calculated and compared to finite element analysis and, for the fundamental eigenvalue, to the exact solution given by Shibaoka (1956).

scholarly journals Properties Analysis of Oil Shale Waste as Partial Aggregate Replacement in Open Grade Friction Course

2018 ◽  
Vol 8 (9) ◽  
pp. 1626 ◽  
Author(s):  
Wei Guo ◽  
Xuedong Guo ◽  
Xing Chen ◽  
Wenting Dai
Keyword(s):  
Oil Shale ◽  
Economic Benefits ◽  
Bending Test ◽  
Fine Aggregate ◽  
Splitting Test ◽  
Marshall Test ◽  
Open Graded Friction Course ◽  
Beam Bending ◽  
Strength And Stiffness ◽  
Styrene Butadiene

Open graded friction course (OGFC) is a high permeable mixture used to reduce noise, improve friction. However, limitations with the use of OGFC are due to the relatively low strength and stiffness. Therefore, investigating environmental and economic benefits, as well as service life of OGFC technology is the future of the pavement. In this study, a new modified OGFC (SM-OGFC) was prepared by replacing the fine aggregate below 4.75 mm in OGFC with the oil shale waste (OSW), and the silane coupling agent modifier was used to assist modification. The preparation process of SM-OGFC was optimized by central composite design, to obtain an SM-OGFC with the best mechanical properties. The Marshall test, rutting test, −15 °C splitting test, −10 °C beam bending test, immersion Marshall test, spring-thawing stability test, Cantabro test and permeability test were conducted to evaluate the properties of SM-OGFC. The results prove that SM-OGFC has excellent overall performance in comparison with OGFC and styrene-butadiene-styrene (SBS) modified OGFC. Furthermore, Scanning Electron Microscopy (SEM) observation illustrates that the unique laminar columnar connected structure and cell-like structure antennae of OSW could be the main reasons why SM-OGFC obtained excellent performance. Furthermore, economic analysis indicated that the SM-OGFC mixture had higher cost effectiveness.

Calibration of pneumotachographs using a calibrated syringe

2003 ◽  
Vol 95 (2) ◽  
pp. 571-576 ◽  
Author(s):  
Yongquan Tang ◽  
Martin J. Turner ◽  
Johnny S. Yem ◽  
A. Barry Baker
Keyword(s):  
Calibration Method ◽  
Linear Range ◽  
Data Sets ◽  
Constant Flow ◽  
Calibration Constant ◽  
Third Order ◽  
Polynomial Coefficients ◽  
Calibration Curves ◽  
Order Polynomial ◽  
Better Than

Pneumotachograph require frequent calibration. Constant-flow methods allow polynomial calibration curves to be derived but are time consuming. The iterative syringe stroke technique is moderately efficient but results in discontinuous conductance arrays. This study investigated the derivation of first-, second-, and third-order polynomial calibration curves from 6 to 50 strokes of a calibration syringe. We used multiple linear regression to derive first-, second-, and third-order polynomial coefficients from two sets of 6–50 syringe strokes. In part A, peak flows did not exceed the specified linear range of the pneumotachograph, whereas flows in part B peaked at 160% of the maximum linear range. Conductance arrays were derived from the same data sets by using a published algorithm. Volume errors of the calibration strokes and of separate sets of 70 validation strokes ( part A) and 140 validation strokes ( part B) were calculated by using the polynomials and conductance arrays. Second- and third-order polynomials derived from 10 calibration strokes achieved volume variability equal to or better than conductance arrays derived from 50 strokes. We found that evaluation of conductance arrays using the calibration syringe strokes yields falsely low volume variances. We conclude that accurate polynomial curves can be derived from as few as 10 syringe strokes, and the new polynomial calibration method is substantially more time efficient than previously published conductance methods.

Elastoplastic Analysis of a Miniature Circular Disk Bending Specimen

2008 ◽  
Vol 130 (4) ◽  
Author(s):  
Vishnu Verma ◽  
A. K. Ghosh ◽  
G. Behera ◽  
Kamal Sharma ◽  
R. K. Singh
Keyword(s):  
Finite Element ◽  
Analytical Solutions ◽  
Material Properties ◽  
Finite Element Solution ◽  
Bending Test ◽  
Experimental Result ◽  
Strain Hardening Exponent ◽  
Plastic Behavior ◽  
Element Solution ◽  
Element Analysis

The miniature disk bending test is used to evaluate the mechanical behavior of irradiated materials and their properties (e.g., yield stress and strain hardening exponent) to determine mainly ductility loss in steel due to irradiation from the load-deflection behavior of the disk specimen. In the miniature disk bending machine the specimen is firmly held between the two horizontal jaws of punch, and an indentor with a spherical ball travels vertically. Analytical solutions for large amplitude plastic deformation become rather unwieldy. Hence, a finite element analysis has been carried out. The finite element model considers contact between the indentor and test specimen, friction between various pairs of surfaces, and elastic plastic behavior. This paper presents the load versus deflection results of a parametric study where the values of various parameters defining the material properties have been varied by ±10% around the base values. Some well-known analytical solutions to this problem have also been considered. It is seen that the deflection obtained by analytical elastic bending theory is significantly lower than that obtained by the elastoplastic finite element solution at relatively small values of load. The finite element solution has been compared with one experimental result and values are in reasonably good agreement. With these results it will be possible to determine the material properties from the experimentally obtained values of load and deflection.

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