Acoustic emission from a SiC reinforced Al-2618 metal matrix composite during straining

摘要: Acoustic emissions can be detected from Al-2618 alloys in the peak aged condition prior to its tensile failure. These events are associated with nucleation of voids by brittle fracture FeNiAl{sub 9} dispersoid phase. When 10{micro}m SiC reinforcements incorporated into alloy rupture dispersoids is suppressed and reinforcing particles begins at a plastic strain 0.5--1.0%. The rate acoustic as function increases rapidly about 10{sup {minus}3} m{sup s{sup {minus}1} 2.0--2.5% both quenched particle reinforced metal matrix composites (PRMMCs). appears little greater case PRMMC but difference not sufficient outside potential experimental scatter. tests interrupted specimens held under constant load AE still continue static load. per second which these occur decays over few seconds. reason for this time dependent behavior unclear. However, it indicates that any constitutive law developed predict functionmore » will also dependent.« less