Method for predicting damage width of rotary ultrasonic hole machining outlet of vehicle hard and brittle material

Abstract

The invention discloses a method for predicting the damage width of a rotary ultrasonic hole machining outlet of an automotive hard and brittle material. The method comprises the following steps: (1)determining the maximum cutting force and subsurface crack depth of abrasive particles on the end surface of a cutter; (2) establishing a theoretical relation model between the subsurface crack depthand the maximum cutting depth of the abrasive particles; (3) determining the number of abrasive particles on the end face of the cutter and the average cutting force of the cutter; (4) determining themaximum cutting force of the cutter and the maximum additional bending moment acting on the edge of the machining surface; (5) establishing a relation model between the stress intensity factor and the maximum subsurface crack depth and the maximum additional bending moment; (6) establishing a relationship between the theoretical thickness of the outlet damage and the maximum subsurface crack depth; and (7) establishing a theoretical relationship between the outlet damage width and the average cutting force of the cutter. According to the method, various factors are comprehensively considered,prediction of the outlet damage width in the machining process of the rotary ultrasonic hole of the automotive hard and brittle material is achieved, and the prediction precision is improved.

Description

technical field [0001] The invention relates to the technical field of rotary ultrasonic hole machining, in particular to a method for predicting the damage width of the exit of rotary ultrasonic hole machining of hard and brittle materials for vehicles. Background technique [0002] The inherent high strength, good wear resistance, low thermal conductivity, low density and low expansion coefficient of structural ceramics make them widely used in the manufacture of engines and heat exchange parts. In addition, ceramics have strong corrosion resistance and good thermal stability at high temperatures, and are widely used in the manufacture of spark plug substrates for gasoline engine ignition systems. However, as a typical hard and brittle material, during the hole machining of structural ceramics, the large extrusion force of the tool-workpiece inevitably causes edge damage at the hole exit position, which seriously reduces the assembly accuracy and structural integrity, and ...

AI Technical Summary

Problems solved by technology

[0007] The present invention aims at the failure of the existing method for predicting the exit damage width during the rotary ultrasonic hole machining of hard and brittle materials for vehicles in the field to consider the influence of the maximum additional bending moment and the maximum depth crack on the exit damage width of the hole, resulting in poor prediction accuracy and reliability. Low problem, the present invention provides a method for predicting the exit damage width of the rotary ultrasonic hole machining of hard and brittle materials for vehicles, so as to realize accurate prediction of the exit damage width during the process of rotary ultrasonic hole machining of hard and brittle materials for vehicles

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