Research on tool path planning method of four-axis high-efficiency slot plunge milling for open blisk

The great mass of machining allowance for blisk is removed in the rough milling, so improving the rough machining efficiency for the blisk's tunnel is the key of realizing high-efficiency machining of blisk. According to the structure characteristic of open blisk's tunnel, a four-axis plunge slot rough milling with high-efficiency and low machining cost is advanced. First, the plunge slot process for blisk and the generation process of the ruled enveloping surface for the freeform surface of the blisk's blade are put forward. Then, the generating method of the ruled enveloping surface for the blade's freeform surface and the tool path generation method of four-axis plunge slot milling for blisk are studied. The rough milling region of open blisk's tunnel is determined by generating the ruled enveloping surface of blade's offset surface, and the algorithm of tool path for four-axis plunge milling is given. When using a ruled surface to approach a freeform surface, the problem of getting boundary is solved, and the error from the calculation of tool path is avoided by the algorithm. At last, the experiment shows that comparing to the traditional side slot milling, the cutting force of four-axis plunge milling can be reduced by 60% and even the rough machining efficiency can be increased to more than double.