Effect of thermal cycling on the damping behavior in alumina borate whisker with and without Bi2O3 coating reinforced pure aluminum composites

• Composites were undergone thermal cycles in damping measurements.
• Damping behavior was studied of the composites during heating and cooling.
• Damping curves of composites are different between heating and cooling.
• A new damping peak was found during cooling in ABOw/Bi/Al composite.

Alumina borate whiskers with and without Bi2O3 coatings reinforced pure aluminum composites were fabricated by squeeze casting. The damping behavior of the composites was described. Samples had undergone thermal cycling during the damping measurement. For the Al18B4O33w/Al composite, two damping peaks are present either in the heating or in the cooling process. For the Al18B4O33w/Al composite with whisker coatings, there are also two damping peaks in the heating process, but there are three damping peaks in the cooling process. The research results indicate that a distinct difference presents in the damping-temperature curves for the Al18B4O33w/Al composite with and without whisker coatings. The damping behavior and damping mechanism in the composites during thermal cycling are explained through dislocation motion, interfacial and grain boundary slip.