An Experimental Study on the Creep Behavior of Al 1050/Mg AZ31B Bilayer Sheet Fabricated via Roll Bonding

This article presents an experimental study on the mechanical properties, creep behavior, and microstructure of an Al 1050/Mg AZ31B-laminated metal composite (LMC), due to limited studies in the analysis of creep and prediction of its behavior for the first time. The fabrication process involved preheating Al 1050 and Mg AZ31B sheets to 400 degrees C for 20 min, followed by rolling with a 40% reduction ratio in thickness. The investigation of mechanical properties and creep behavior under three different loadings, namely 35 MPa at 225 degrees C, 35 MPa at 275 degrees C, and 30 MPa at 225 degrees C, revealed the formation of a 6.7-micron atomic diffusion layer at the interface during roll bonding. With the increasing temperature at constant stress, an intermetallic compound formed adjacent to the aluminum, resulting in a 68% increase in interface thickness and a 36% decrease in creep failure time due to strength reduction. However, an increase in stress levels at a constant temperature did not have a significant effect on the interface thickness, as it only decreased by 13% and the creep failure time did decline by 44%. It can be observed that creep curves are influenced by the applied stress and temperature. Specifically, the slope of the curve increased by 40% with higher stress levels, while it decreased by approximately 2% with higher temperatures. Additionally, recrystallization was seen in the microstructure of the laminated metal sheet, whereas deformation bands and solidified melts were observed in the magnesium microstructure.