A Correlation Between Failure Angle and Constituent for Al-AlN Composites Under Uniaxial Tensile Conditions

Al-AlN composites with different AlN reinforcement fractions and porosity were fabricated through nitridation of laser-sintered AA 6061 powder followed by infiltration with AA 6061. Their failure behaviors were investigated under uniaxial tensile loading conditions. Tensile testing and fractography indicate that the fracture mode changes gradually from ductile to brittle fracture with increasing AlN reinforcement or porosity. An analysis of the fractured Al-AlN tensile samples reveals that the failure surface angle, theta, is dictated by the volume fraction of the matrix, f (m) , in a form of tan theta = f (m) (5.5) .