0
Research Papers: Design and Analysis

A 3-D Model for Evaluating the Residual Stress Field Due to Swage Autofrettage

[+] Author and Article Information
J. Perry, M. Perl

Pearlstone Center for Aeronautical Engineering Studies, Department of Mechanical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel

J. Pressure Vessel Technol 130(4), 041211 (Oct 02, 2008) (6 pages) doi:10.1115/1.2967741 History: Received September 26, 2006; Revised April 24, 2007; Published October 02, 2008

In order to maximize the performance of modern gun barrels in terms of strength-to-weight ratio and total fatigue life, favorable compressive residual stresses are introduced to the inner portion of the barrel, commonly by the autofrettage process. There are two major autofrettage processes for overstraining the tube: the hydrostatic and the swage. There are several theoretical solutions for hydrostatic autofrettage based on Lamé’s solution and the von Mises or Tresca yield criteria. The residual stress field due to hydraulic autofrettage is treated as an axisymmetric two-dimensional problem solved in terms of the radial displacement solely. Once the Bauschinger effect was included in these models they yield very realistic results. Unlike in the case of hydraulic autofrettage, swage autofrettage needs to be modeled by a three-dimensional model. The present analysis suggests a new 3-D axisymmetric model for solving the residual stress field due to swage autofrettage in terms of both the radial and the axial displacements. The axisymmetric equilibrium equations are approximated by finite differences and solved then by Gauss–Seidel method. Using the new computer code the stresses, the strains, the displacements, and the forces are determined. A full-scale instrumented swage autofrettage test was conducted and the numerical results were validated against the experimental findings. The calculated strains, the permanent bore enlargement, and the mandrel pushing force were found to be in very good agreement with the measured values.

FIGURES IN THIS ARTICLE
<>
Copyright © 2008 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Pressure distribution for simulating swage autofrettage

Grahic Jump Location
Figure 2

Compressive yield stress Bauschinger effect factor (14)

Grahic Jump Location
Figure 3

Pressure curve-radial displacement optimization

Grahic Jump Location
Figure 4

Axial stress equilibration

Grahic Jump Location
Figure 5

Comparison between 3-D and 2‐D+ residual stress components

Grahic Jump Location
Figure 6

Residual stress distribution for b∕a=2.7, 92% overstrain

Grahic Jump Location
Figure 7

Residual stress distribution for b∕a=2.7, 62% overstrain

Grahic Jump Location
Figure 8

Residual stress distribution for b∕a=2.2, 87.5% overstrain

Grahic Jump Location
Figure 9

Residual stress distribution for b∕a=2.2, 58% overstrain

Grahic Jump Location
Figure 10

Typical experimentally measured residual stress distributions (6)

Grahic Jump Location
Figure 11

The external radial and tangential strain distributions

Grahic Jump Location
Figure 12

The numerical and the experimental strains on the cylinder’s external surface

Grahic Jump Location
Figure 13

Comparison between O’Hara’s and the present residual stress fields (excluding Bauschinger effect)

Grahic Jump Location
Figure 14

Comparison of the residual stress fields including the Bauschinger effect

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In