Hertz Contact Stress Calculator

Calculate contact stress, contact width, and approach distance for cylinder-on-cylinder and sphere-on-sphere contact using Hertzian theory.

Normal force pressing the two bodies together.
N
Radius of curvature of first body. Use large value for flat surface.
mm
Radius of curvature of second body.
mm
Young's modulus. Steel: 207 GPa, Aluminum: 69 GPa.
GPa
Young's modulus of second body.
GPa
Axial length of contact (for cylinder contact).
mm

Results

Max Contact Pressure-MPa
Half Contact Width-mm
Equivalent Radius-mm
Equivalent Modulus-GPa
References: Shigley's Ch. 3 — Contact Stresses; Roark's Formulas for Stress and Strain