50 %
50 %
Information about FatigueFactors

Published on January 25, 2008

Author: Patrizia

Source: authorstream.com

Factors that Affect the Fatigue Life of Rubber: A Literature Survey:  Factors that Affect the Fatigue Life of Rubber: A Literature Survey W. V. Mars* - Cooper Tire & Rubber Co. A. Fatemi - U. of Toledo Paper #6 (the paper can be purchased at www.rubber.org) ACS Rubber Division Meeting Savannah, Georgia April 29, 2002 *Speaker, wvmars@coopertire.com Overview:  Overview Part I - “A Literature Survey on Fatigue Analysis Approaches for Rubber”, W. V. Mars, A. Fatemi, Int. J. Fatigue, Vol. 24, No. 9, pp. 949-961, 2002. Crack Nucleation Approach (S-N style) Crack Growth Approach (dc/dn = f(T)) Today - Important Factors Mechanical Load History Environmental Conditions Rubber Formulation Stress-Strain Behavior Parameters for Simple Histories:  Parameters for Simple Histories Effect of Minimum Strain:  Effect of Minimum Strain Cadwell et al, Ind. Eng. Chem., Anal. Ed., 12, 19 (1940) Filled NR Effects of Max. SERR & R-Ratio:  Effects of Max. SERR & R-Ratio Lindley, Int. J. Fracture, 9, 449 (1973) Unfilled NR Effect of Static Period under Strain:  Effect of Static Period under Strain Roland, Sobiesky, RCT, 62, 683 (1989) Polyisoprene Effect of Load Sequence:  Effect of Load Sequence Sun et al, TSTCA, 28, 196 (2000) Effect of Waveform:  Effect of Waveform Hardy et al, RubberChem ‘99, Paper #2, Antwerp, Belgium, (1999) (Both compounds based on BIIR) Compound A Compound B Pulse Sine Effect of Strain Rate:  Effect of Strain Rate Young, RCT, 59, 809 (1986) Unfilled CIIR Unfilled NR Multiaxial Loading:  Multiaxial Loading Undeformed Deformed H δ max δ min 1 2 Cadwell et al, Ind. Eng. Chem., Anal. Ed., 12, 19 (1940) Applied Loads Crack Loading? Crack Closure? Material property dependence on multiaxial loading? http://www.umi.com/hp/Products/Dissertations.html - “Multiaxial Fatigue of Rubber”, by W. V. Mars, U. of Toledo, 2001 Effect of Temperature:  CIIR Natural Rubber BR Effect of Temperature Young, RCT, 59, 809 (1986) Temperature and To?:  Temperature and To? L Plane of Crack Propagation n monomer units crosslink crosslink Crack tip - Undeformed State Lake & Thomas, Proc. Roy. Soc. Lon., A, 300 , 108 (1967) Effects of Ozone and Oxygen:  Effects of Ozone and Oxygen Young, RCT, 59, 809 (1986) CIIR Natural Rubber Electrical Charges?:  Electrical Charges? Electro- & tribo- elastic effects cause electric charges to accumulate under cyclic deformation. Metallic grips grounded, then insulated. Effect on fatigue resistance. Grounded condition gives longer fatigue life Larger filler loading - larger effect Dogadkin et al, RCT, 33, 970 (1960) Polymer / Filler Effects:  Polymer / Filler Effects + Gum Filled with 50 phr N300 carbon black (fine) Lake & Lindley, Rubber J., 146 (10), 24 (1964) Filled with 50 phr N900 carbon black (coarse) Antidegradants:  Antidegradants Lake & Lindley, Rubber J., 146 (10), 24 (1964) Air, Gum NR, No AO Vaccum, Gum NR, No AO Air, Gum NR, +AO Proposed Effect of Hysteresis:  Proposed Effect of Hysteresis Lake & Thomas, Proc. Roy. Soc. Lon., A, 300 , 108 (1967) Strain Crystallization:  Strain Crystallization Choi & Roland, RCT, 70, 202 (1997) The Mullins Effect:  The Mullins Effect Progressively Increasing Simple Tension, N = 8 time strain Mars, Ph.D. Dissertation, U. Toledo, (2001) Tc and Loss Modulus:  Tc and Loss Modulus Mullins, Trans. IRI, 35, 213 (1959) Data points are for various butadiene-styrene and butadiene-acrylonitrile co-polymers Summary Mechanical Load History:  Summary Mechanical Load History Alternating Load and Maximum Load Minimum Load, Mean Load, R-Ratio Statically Strained Rest Period Load Sequence Multiaxial Loading Frequency / Waveform Summary Environmental Conditions:  Summary Environmental Conditions Temperature Ozone Oxygen Electrical Charges? Summary Rubber Formulation:  Summary Rubber Formulation Polymer Type Filler Type and Loading Antidegradants Vulcanization Summary Stress-Strain Behavior:  Summary Stress-Strain Behavior Strain-Crystallization Mullins Effect Rate-Independent Hysteresis Viscoelasticity Questions and Discussion:  Questions and Discussion

Add a comment

Related presentations

Related pages

Employers Can Control Some Fatigue Factors

Automated translations are provided by Google Translate, a third party service which SHRM does not control. This translation does not serve as an official ...
Read more

Strength, Fatigue and Fracture

Factors Influencing Fatigue . Mean Stress . Professor Darrell F. Socie . Mechanical Science and Engineering . University of Illinois © 2004-2013 Darrell ...
Read more

Fatigue Factors - iSixSigma

Home › Forums › Old Forums › General › Fatigue Factors. This topic contains 0 replies, has 1 voice, and was last updated by Robert DeBaets 9 years, ...
Read more

Fatigue - IMO

At its 18th session in November 1993, the IMO Assembly adopted resolution A.772(18) on fatigue factors in manning and safety. The resolution recognizes ...
Read more

Fatigue - worksafe.vic.gov.au

Fatigue. Your health and safety guide to Fatigue; ... About fatigue Factors contributing to fatigue What are the risks? Your Legal Duties Employers Employees
Read more

Click for More: The Fatigue Factor - SHRM Online

Thanks for reading HR Magazine's "Click for More." Sorry for the inconvenience, we set up this page so we could measure readership. Ready to see the item ...
Read more


ANNEX FATIGUE FACTORS IN MANNING AND SAFETY 1 INTRODUCTION 1.1 The purpose of this document is to provide a general description of fatigue, to identify the ...
Read more

eFatigue - Training and Seminars

Training and Seminars. The eFatigue staff provides on-site training in all aspects of fatigue and fatigue analysis. This includes both customized training ...
Read more

Factors Contributing To Fatigue - vwa.vic.gov.au

Factors contributing to fatigue - [enter summary here] ... The factors contributing to fatigue outlined in this guide are: the mental and physical demands ...
Read more