Share Email Print
cover

Proceedings Paper

Self-healing bolted joint employing a shape memory actuator
Author(s): Daniel E. Muntges; Gyuhae Park; Daniel J. Inman
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

This paper is a report of an initial investigation into the active control of preload in the joint using a shape memory actuator around the axis of the bolt shaft. Specifically, the actuator is a cylindrical Nitinol washer that expands axially when heated, according to the shape memory effect. The washer is actuated in response to an artificial decrease in torque. Upon actuation, the stress generated by its axial strain compresses the bolted members and creates a frictional force that has the effect of generating a preload and restoring lost torque. In addition to torque wrenches, the system in question was monitored in all stages of testing using piezoelectric impedance analysis. Impedance analysis drew upon research techniques developed at Center for Intelligent Material Systems and Structures, in which phase changes in the impedance of a self-sensing piezoceramic actuator correspond to changes in joint stiffness. Through experimentation, we have documented a successful actuation of the shape memory element. Due to complexity of constitutive modeling, qualitative analysis by the impedance method is used to illustrate the success. Additional considerations encountered in this initial investigation are made to guide further thorough research required for the successful commercial application of this promising technique.

Paper Details

Date Published: 16 August 2001
PDF: 8 pages
Proc. SPIE 4327, Smart Structures and Materials 2001: Smart Structures and Integrated Systems, (16 August 2001); doi: 10.1117/12.436530
Show Author Affiliations
Daniel E. Muntges, Virginia Polytechnic Institute and State Univ. (United States)
Gyuhae Park, Virginia Polytechnic Institute and State Univ. (United States)
Daniel J. Inman, Virginia Polytechnic Institute and State Univ. (United States)


Published in SPIE Proceedings Vol. 4327:
Smart Structures and Materials 2001: Smart Structures and Integrated Systems
L. Porter Davis, Editor(s)

© SPIE. Terms of Use
Back to Top