EFFECT OF MANUFACTURING PROCESS CHARACTERISTICS OF SUS316L STAINLESS　STEEL HIGH-STRENGTH BOLTS ON STRESS CONCENTRATION AT SCREW PART AND　UNDERHEAD FILLET

Abstract

To develop a stainless steel high-strength bolt with higher corrosion resistance for use in joining stainless steel members, a prototype bolt was made from SUS316L. To increase the strength of the bolt, a wire-drawing process was used instead of the more common heat-treatment method. As a result, it was found that the elastic modulus of the shaft cross-section decreased continuously from the core to the surface. The modeling of a bolt with this feature was examined by considering various factors, and the effects of the feature on the stress concentration in the radius of the lower neck and thread were studied analytically.