Influence of Microstructure Difference of Stainless Steels on the Strength and Fracture of Bolted Connections

Abstract

Recently, since stainless steel has a variety of significant characteristics such as corrosion resistance, durability, aesthetic appeal and fire resistance, the use of stainless steel in construction has been steadily increasing. Also, stainless steels can be classified into five main groups; austenitic, ferritic, martensitic, duplex and precipitation hardening according to metallurgical microstructure. Austenitic stainless steels are the most widely utilized in buildings. This paper focused on comparing material properties and ultimate behaviors such as strength, fracture mode and curling effect of single shear bolted connections fabricated with two different stainless steels; austenitic and ferritic types. Bolt arrangement and end distance in the parallel direction of applied load are considered as main variables. Specimens have same edge distance perpendicular to the direction of load, plate thickness, bolt diameter, pitch and gauge. A monotonic tensile test has been carried out for specimens under shear and some bolted connections with long end distance were accompanied by curling; out of plane deformation, which caused strength reduction. Furthermore, it is found that the fracture shape and curling effect patterns of two kinds of bolted connections differ from two stainless steel materials.