Deflection of PDMS ENMA 490 October 16, 2003 Shawna Dean.

Slides:

Advertisements

Similar presentations

Physics 6B Stress, Strain and Elastic Deformations Prepared by Vince Zaccone For Campus Learning Assistance Services at UCSB.

Advertisements

Chapter 13 - Elasticity A PowerPoint Presentation by

STATICALLY DETERMINATE STRESS SYSTEMS

1 MFGT104 Materials and Quality Chap 14: Tensile Testing Viscosity and Melt Index Professor Joe Greene CSU, CHICO MFGT 104.

IE 337: Materials & Manufacturing Processes

Stress, Strain, and elastic moduli

Soil Physics 2010 Outline Announcements Basic rheology Soil strength Triaxial test.

The various engineering and true stress-strain properties obtainable from a tension test are summarized by the categorized listing of Table 1.1. Note that.

ES 246 Project: Effective Properties of Planar Composites under Plastic Deformation.

Designing for Stiffness

Deformation of Solids Stress is proportional to Strain stress = elastic modulus * strain The SI unit for stress is the Newton per meter squared (N/m 2.

CMGT 322 LECTURE 2. FORCES  DEFINE FORCE  DEFINE UNITS FOR FORCES  THREE IMPORTANT FACOR ABOUT FORCES: MAGNITUDE, DIRECTION, SENSE  STRESS= FORCE/AREA.

Lecture # 2 Allowable Stress Objective:

Assist.Prof.Dr. Ahmet Erklig

Mechanics of Materials II

ENGR 225 Section

PLEASE PASS YOUR HOMEWORK TO THE CENTER ISLE TAKE EVERYTHING OFF YOUR DESKS EXCEPT A PENCIL OR PEN AND CALCULATOR: QUIZ TIME 1.

Mechanics of Elastic Materials

Mechanical Properties of Metals

Sheet Metal Bending.

University of Sydney – Structures SECTIONS Peter Smith & Mike Rosenman l The size and shape of the cross- section of the piece of material used l For timber,

CHE 333 Class 11 Mechanical Behavior of Materials.

The ratio of stress and strain, called modulus of elasticity. Mechanical Properties of Solids Modulus of Elasticity.

Stress and Strain  Tensile Stress- the ratio of the magnitude of the applied force F to the cross-sectional area A: Mathematically, Stress= Force/Area=F/A.

Statics Activities. Stress  Force per unit area (  ) Typical engineering units – psi (lb f /in 2 ) – N/m 2 Stress = Force/Area – Applied by external.

Strengths Chapter 10 Strains. 1-1 Intro Structural materials deform under the action of forces Three kinds of deformation Increase in length called an.

Thin Cylinders & Spherical Shells Analysis of above under Pressures.

1 ME383 Modern Manufacturing Practices Lecture Note #3 Stress-Strain & Yield Criteria Dr. Y.B. Guo Mechanical Engineering The University of Alabama.

CTC / MTC 222 Strength of Materials Chapter 1 Basic Concepts.

Chapter 9-Statics, Dynamics and Mechanical Engineering Objectives and what should you Know: What are statics and Dynamics? What are the Newtons’s three.

Lecture 7 Mechanical Properties of Rocks

Strength of Materials Outline Overview AXIALLY LOADED MEMBERS THIN-WALLED CYLINDER GENERAL STATE OF STRESS PLANE STRESS + MOHR’S CIRCLE PLANE STRAIN +

UNIT-01. SIMPLE STRESSES and STRAINS Lecture Number - 02 Prof. M. N. CHOUGULE MECHANICAL DEPARTMENT SIT LONAVALA Strength of Materials.

Machine Design I (MCE-C 203) Mechatronics Dept., Faculty of Engineering, Fayoum University Dr. Ahmed Salah Abou Taleb Lecturer, Mechanical Engineering.

Poisson's ratio, n • Poisson's ratio, n: Units:

Numerical analysis of Concrete Face Rockfill Dams based on Lade’s model and gradient plasticity P. Dakoulas, E. Stavrotheodorou, A. Giannakopoulos University.

Mechanical & Aerospace Engineering West Virginia University Statistics of Brittle Fracture.

Structure and Structural calculation for Recuperative Heat Exchanger Recuperative Heat Exchanger Presented by -- Jinying Zhu.

Copyright Kaplan AEC Education, 2005 Mechanics of Materials Outline Overview AXIALLY LOADED MEMBERS, p. 262 Modulus of Elasticity Poisson’s Ratio Thermal.

EML 4230 Introduction to Composite Materials

Lecture 12. Mechanical Properties. Engineering Stress < True Stress True StressTrue Strain.

MECHANICS OF MATERIALS Fourth Edition Ferdinand P. Beer E. Russell Johnston, Jr. John T. DeWolf Lecture Notes: J. Walt Oler Texas Tech University CHAPTER.

Multilayer Microfluidics ENMA490 Fall 2003 Brought to you by: S. Beatty, C. Brooks, S. Dean, M. Hanna, D. Janiak, C. Kung, J. Ni, B. Sadowski, A. Samuel,

UNIT-3 CIRCULAR PRESTRESSING. Analysis at Service Loads The tensile stress due to the internal pressure (p) can be calculated from the tension T.

Problems 1. A large plate is fabricated from a steel alloy that has a plane strain fracture toughness of 82.4MPa√m. If, during service use, the plate is.

EGM 5653 Advanced Mechanics of Materials

Multilayer Microfluidics ENMA490 Fall 2003 Brought to you by: S. Beatty, C. Brooks, S. Dean, M. Hanna, D. Janiak, C. Kung, J. Ni, B. Sadowski, A. Samuel,

Chapter 12 Lecture 22: Static Equilibrium and Elasticity: II.

Chapter 15 Soil-Bearing Capacity for Shallow Foundations

Materials Science Chapter 8 Deformation and Fracture.

1 Chapter 2: Application of stress EBB 334 Mechanical Metallurgy Assoc. Prof. Dr. Zuhailawati Hussain.

Kalol Institute Of Technical & Research Center

Question 1 A plat that is 250 mm wide and 25 mm thick is to be reduced in a single pass in a two‑high rolling mill to a thickness of 20 mm. The roll has.

Tensile Testing of Aluminum Alloy

Ch. 2: Fundamental of Structure

( BDA 3033 ) CHAPTER 6 Theories of Elastic Failures

9-6 Elasticity; Stress and Strain

Shawna Dean October 28, 2003 ENMA 490

Presentation transcript:

Deflection of PDMS ENMA 490 October 16, 2003 Shawna Dean

Outline Used equations for deflection in rectangular area ‘Breaking pressure’, the minimum pressure that can cause a failure. Calculated with a range of parameters. Especially thickness, because it is our main variable for controlling what pressures we can use.

Deflection Equations and Variables Deflection: w =.00265P(ab)^ 2 /D D=Et^3/(12*(1-v)) Deflection for circular membrane: w = 3Pr 4 (1-v 2 )/(16Et 3 ) P: pressure E: elastic modulus v: poisson’s ration a and b: width and length of membrane r: radius FOR PDMS E (shear): 2.03 x 10 5 MPa v: 0.5

Tensile Strength and Breaking Pressure From the Polymer Data Handbook found a tensile range from Mpa for PDMS, depending on how the polymer was cured during processing. This gives us an idea of the magnitude of stress we can not surpass. Otherwise the membrane will fail. What does this mean to us in terms of pressure? Strain equation for membranes: Strain=0.3081P(ab/t 2 ) oUsing this equation the ‘breaking pressure’ was found to have a magnitude of 1000MPa.

Calculations Thickness (microns) Target Deflection (microns) Resulting Pressure (Mpa) Resulting Pressure (atm)  The chart has several thickness coupled with targeted deflections to get several different pressures needed.  All calculations were assuming a square area, 500 x 500 microns.

Looking Forward All resulting pressures were less than the ‘breaking pressure’ making these dimensions plausible for use. Next steps: Relate pressure to flow rates. All the pressure where calculated so they are positive. We have assumed negative will have the same effect on deflection as positive. Is this true?