Author : National Aeronautics and Space Administration (NASA)
Publisher : Createspace Independent Publishing Platform
Page : 26 pages
File Size : 52,9 Mb
Release : 2018-07-21
Category : Electronic
ISBN : 1723444200
Theoretical Basis for Design of Thermal-Stress-Free Fasteners by National Aeronautics and Space Administration (NASA) Pdf
A theoretical basis was developed for the design of fasteners which are free of thermal stress. A fastener can be shaped to eliminate the thermal stress which would otherwise result from differential thermal expansion between dissimilar fastener and sheet materials for many combinations of isotropic and orthotropic materials. The resulting joint remains snug, yet free of thermal stress at any temperature, if the joint is uniform in temperature, if it is frictionless, and if the coefficients of thermal expansion of the materials do not change with temperature. In general, such a fastener has curved sides; however, if both materials have isotropic coefficients of thermal expansion, a conical fastener is free of thermal stress. Equations are presented for thermal stress free shapes at both initial and final temperature, and typical fastener shapes are shown. Blosser, M. L. and Mcwithey, R. R. Langley Research Center NASA-TP-2226, L-15658, NAS 1.60:2226 RTOP 506-53-43-02
