In the keyway broaching of thin-wall brittle material workpieces, the cracking of the keyway pull-out end often occurs, causing the workpiece to be scrapped, and the workpiece and the cracking position are as shown in Fig. 1. Observing the broaching process, it was found that the cracking always occurred when the keyway depth dimension was close to the requirement. The main reason is that the workpiece wall is too thin and the strength is low. Because the bottom surface of the keyway has a tendency to crack under the action of the pulling force, the groove depth is shallow in the initial stage of the broaching, and the strength of the workpiece can still be satisfied. As the groove depth increases, the bottom of the workpiece keyway becomes thinner and thinner, and the strength becomes weaker and weaker, eventually causing the bottom surface of the keyway to rupture. To this end, the spring collar can be added during broaching, as shown in Figure 2. Spring collar
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