Orthogonal analysis of pressing stress and friction shear stress on low melting point alloy mandrel pressing of the hollow blade with different ribs

With the development of hollow blades, increasingly diverse ribs are set in the blades. However, forming of these hollow blades with ribs using plastic method is still a challenge because of the complex stress. To solve this problem, the mechanical analysis in this paper is conducted in two orthogonal planes for the pressing of hollow blades with a low melting point (LMP) alloy mandrel. The simulated forming surfaces in five hollow blade groups with different ribs are verified by the measured surfaces in experiments. The errors are not only less than 10%, but also decrease with the increase in the number of ribs. Then, more simulated results with three different blade materials TC4, SS304, and AA5052 are used to verify the pressing stresses calculated by the model provided. Finally, the relationship of neutral surfaces of both friction stress and thickness is also proved based on the calculations. The calculated and simulated results are almost matched with each other. All the effects of materials, rib numbers, deformation amount, and metal amount on the stresses are discussed. This paper not only provides a detailed account of the mechanical mechanism of the hollow blade pressing with LMP mandrel, but also shows an example of orthogonal mechanical analysis in two planes.