Abstract
The mechanical healing of KCl single crystals has been investigated under atmospheric pressure at room temperature. A crack was introduced by a utility knife and then fractured by tensile load. The healing process can be divided into three stages. The first and the second stages correspond to the progressive healing in fractures arising from the tensile load and the utility knife, respectively. The third stage happens when the compression load is still applied after the above two stages. The healing rate is related to the morphology of the fracture surfaces and the employed strain rate, but is independent of the compressive load. The effect of strain rate on fracture toughness for healed material is opposite to that for virgin material.