[Fatigue properties of gallium alloy].

Gallium alloys that have been developed as a substitute for dental amalgam were investigated for fatigue properties and the effects of environmental factors were also examined. Cylindrical specimens were fatigue-tested employing cyclic tensile loading. Statistical definition of the fatigue limit at 10(5) cycles was obtained according to the staircase method. The significance of environmental factors were evaluated by analysis of variance using the orthogonal table L8 (2(7)). The fatigue limit of gallium alloys was higher than that of a conventional high copper amalgam and was influenced by the experimental environment such as temperature and water. The fatigue fracture occurred in the matrix and the interface between the matrix and the core. Gallium alloys have excellent fatigue properties as a filling material.