Heating by an electromagnetic field is an effective method for stopping internal crack propagation in metal components, thus extending their service life by improving safety and reliability. Experimental surveys show that a small spherical crater can be formed near the crack tip using a concentrated current which melts metal at the desired point. Experiments also show that the sharp point around the crack tip is rounded, which decreases the stress concentration and forms a compressive stress area. The structure around the crack tip is refined obviously. At the same time, a white-bright layer is formed around the crack tip under the influence of a precipitous temperature gradient. Thermal compressive stresses and phase transformation stresses, together with the influence of a super-fine microstructure, promote the ability of metals to withstand intense wear. From the experiments we also find many factors have an effect on the efficiency of crack arresting.