Ansys Employee
An element will be eroded if its erosion criteria is exceeded - whether it's part of a "fragment", or not. Under *MAT_015, the manual states: "Fracture occurs when the damage parameter reaches the value of 1. D is stored as extra history variable 4 in shell elements and extra history variable 6 in solid elements." Erosion can also be due to *MAT_ADD_EROSION, if that keyword is applied to the *MAT_015 part.