Contact Stresses

December 31, 2024

PRESENTER: Steven R. Schmid, Professor of Mechanical Engineering, University of Notre Dame


This is a webinar for design engineers. The presentation will be fairly technical, but will be easily understood by anyone with a technical bachelor’s degree.


This webinar will cover the stresses that result in gear tooth contact, including Hertzian contact stress theory, and point and line contacts.  Professor Schmid will also extend the discussion to cover elliptical contact and the application to gears.  


Following this webinar, attendees will be able to –

  • Appreciate the nature of nonconformal contacts, their stresses and benefits of lubrication
  • Calculate the contact stresses and deformations associated with gear contacts of all kinds
  • Understand the basic scientific background of the AGMA contact stress equations


  • Strength of gears, including effects of manufacturing process on gear quality index and associated costs; stress cycle factors and other modifications; effect of lubrication regime 
  • An introduction to bending of gear teeth, the factors that affect stress and strength, and the design approaches to reduce bending stresses
  • The nature of fatigue wear, methods to eliminate or reduce fatigue wear (pitting resistance)
  • Application of lubrication theory to gears
  • The AGMA equations and their relationship to Hertzian contact

You will have 30 days to view the archived webinar.