Size Effect on Deformation Behavior and Fracture in a Pure Copper Microtensile Test

Pure copper specimens 0.1, 0.2, and 0.3 mm thick were annealed at different temperatures. The influence of the size effect on the mechanical properties and fracture behavior of annealed pure copper was investigated in a uniaxial tensile test. The elongation and tensile strength decreased with the grain size at a constant specimen thickness. If the grain size remains constant and its thickness varies, the tensile strength and elongation increase with the specimen thickness. The specimen grain size and thickness can significantly affect the fracture behavior of pure copper. If the grain size is increased and the specimen thickness is reduced, the fracture behavior tends to change from a mixed fracture mode to a slip fracture one.