Blisk Stub Geometry for Linear Friction Welding

The patent applies local quality by varying the stub width along its length to create different local conditions for flash burn-off. The stub has a first width at the leading edge, a second width at the trailing edge, and a third width at the mid-chord position, with the ratio of maximum to minimum width being less than 2. This non-uniform width distribution compensates for position-dependent burn-off rates, ensuring consistent weld quality across the entire stub while maintaining manufacturability.

The patent applies parameter changes by modifying the geometric parameters of the stub (width at leading edge, trailing edge, and mid-chord positions) to compensate for elastic deflections and energy input variations. Instead of using complex machine and tooling systems to actively control and compensate for these variations, the invention embeds the compensation directly into the stub's geometry, thereby maintaining weld quality while significantly reducing device complexity.

The patent applies partial or excessive action by implementing a controlled width variation in the stub that is sufficient to manage flash burn-off but does not require extreme precision. The ratio of maximum to minimum width is specified to be less than 2, which provides adequate flash control while avoiding overly stringent manufacturing precision requirements. This moderate approach balances flash management needs with practical manufacturability.