Deformation Characteristics and Ductile Fracture of 1040 Steel in Simple Upsetting of Solid Cylinders and Rings

Abstract

Experiments were conducted involving the upsetting of solid cylinders and rings of annealed SAE 1040 steel at room temperature for various end conditions. Measurements were made on the displacement distributions at the tool-workpiece interface, and on the development of barreling and strain variations at the free surface. Crack formation at the free surface was observed. The relationship between friction at the interface, deformation characteristics, and fracturing is discussed, and a tentative analysis is given for formulating the strains at the free surface, based on the experimental measurements for upsetting solid cylinders.