The Analysis of Fracture Phenomenon of the Deformed Aluminum-Copper Bimetallic Sheet in the Single Point Incremental Forming

Document Type : Original Article

Authors

Ali Zahedi

Zahra Sadat Amini

Seyed Mohammad Arab

Department of Materials and Manufacturing, University of Mohaghegh Ardabili, Ardabil, Iran.

10.22067/jacsm.2025.95791.1365

Abstract

In this study, the fracture behavior of aluminum-copper bimetallic sheet during single-point incremental forming process has been analyzed during experimental tests. For this purpose, the bimetallic sheet was produced by explosive welding method and then deformed during incremental forming process. To provide a basis for comparison with the uniaxial stress condition, uniaxial tensile tests were also conducted on the bimetallic sheets. Microstructural examinations of the fracture zones in both conditions were carried out using optical microscopy (OM) and scanning electron microscopy (SEM). The tensile test results indicated that the fracture strength of the bimetallic specimen increased by 70% compared to the monolithic aluminum sheet, reaching 317 MPa, while elongation improved from 8.5% to 7.5%, suggesting higher toughness in the bimetallic sample. Moreover, fracture surface observations revealed that aluminum exhibited brittle behavior, whereas copper showed ductile fracture under both incremental forming and uniaxial tensile loading. The interfacial microstructure contained intermetallic compounds, and energy-dispersive spectroscopy (EDS) confirmed hardness increase within the bonding region.

Keywords

Bimetallic Sheet

Fracture Surface

Microstructure

SEM

Subjects

• Forming

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