Ultrahard-material special-shaped component tensioning positioning tool assembly and milling method

Abstract

The invention discloses an ultrahard-material special-shaped component tensioning positioning tool assembly and milling method. The method comprises the following steps of discharging materials; rough-machining a special-shaped component; making a reserved clamping process step on the reference surface of the component; making process threaded holes in the reserved clamping process step for beingconnected with tools for tensioning positioning during positioning clamping; machining a groove at the bottom of the process step; performing quenching treatment; making the process threaded holes inthe process step surface; performing semi-finish machining by taking the process plane as a reference plane, and performing semi-finish machining on the step surface of the semi-finish milling processby using a milling cutter; performing aging treatment; finding a reference plane and finish-machining a reference hole with a margin to obtain a final reference hole; using a first tensioning tool component to complete semi-finish milling of each profile; performing finish machining, wherein a second tensioning positioning tool component is used for tensioning and positioning, and performing bottom-tooth micro-cutting machining by adopting a fine milling cutter; and removing the process step. The method enables efficient machining of ultrahard material special-shaped components.

Description

technical field [0001] The invention belongs to the technical field of numerical control machining, and in particular relates to a tensioning and positioning tool assembly and a milling method for a special-shaped member of superhard material. Background technique [0002] Special-shaped components are widely used in mechanical transmission mechanisms, and their machining dimensional accuracy, surface roughness, and shape and position tolerances directly affect the performance indicators of mechanism transmission. Since this type of component has the characteristics of complex dimensional structure, high dimensional accuracy and strict geometrical tolerance, especially the component is easy to deform, the geometrical tolerance accuracy of key features relative to the reference is a key technology that needs to be solved. At the same time, the material is a superhard material. The quenching hardness reaches HRC40-45, and its processing method has always been a technological p...

AI Technical Summary

Problems solved by technology

Since this type of component has the characteristics of complex dimensional structure, high dimensional accuracy and strict geometrical tolerance, especially the component is easy to deform, the geometrical tolerance accuracy of key features relative to the reference is a key technology that needs to be solved. At the same time, the material is a superhard material. The quenching hardness reaches HRC40-45, and its processing method has always been a technological problem that plagues scientific research and production

[0003] For the processing of special-shaped components, the current method is to use a universal fixture (flat pliers) on both sides of the flat part of the component on a five-axis machine tool (the clamping allowance is left at the bottom of the clamping part of the component), and the radial cutting mode of a cylindrical milling cutter is adopted. Processing, due to the influence of comprehensive factors such as cutting force, clamping force, cutting heat and material stress release, the processing quality is difficult to guarantee. The background technology mainly has the following deficiencies:

[0004] 1. During the clamping process of special-shaped components, the clamped part of the workpiece needs to be positioned by the clamping force of the flat-nose pliers. The characteristics of each spatial position are kept in a relatively balanced state with respect to the reference elements. When the component is slightly deformed after clamping, it is completed. The cutting process has met the precision requirements, but as soon as the clamping is released, the clamping deformation will be restored, and the clamping deformation is unavoidable, thus losing the achieved precision, and the tolerance accuracy of various shapes and positions drifts, which cannot meet the precision requirements

[0005] 2. The quenching hardness of the superhard material of the special-shaped component is as high as HRC40-45, and the cutting performance is poor. The dimensional accuracy of the key processed surface of the component is ≤0.02mm, and the symmetry is ≤0.05mm. During the cutting process, it is easy to produce sticking knife and cutting edge cutting tumor In other conditions, the tool is easy to wear, the surface size is easy to process drift (drift ≥ 0.02mm), and the symmetry ≥ 0.15mm will destroy the geometric accuracy and surface roughness of the machined surface of the component. These comprehensive factors lead to the surface dimensional accuracy Insufficient accuracy of geometric and geometric tolerances

The longer the length-to-diameter ratio of the milling cutter, the weaker the rigidity, and the resulting feature size deviation exceeds the tolerance zone required by the process

[0007] 4. The metal removal rate of special-shaped components is high, and the uneven removal allowance during processing will cause the internal residual stress balance state of the component to be destroyed, and the component will be deformed. The last working step after machining is to remove the clamping margin at the bottom of the clamping part of the component, a large amount of margin is removed at once, causing the residual stress to be released locally, and the dimensional tolerances and shape and position tolerances of the components lose the achieved accuracy. The accuracy of various geometric tolerances drifts

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