Resonant fatigue testing machine dynamic load error online compensation method

Abstract

A resonant fatigue testing machine dynamic load error online compensation method comprises following steps: (1) establishing a compact tension (CT) specimen connection rigidity model and a three freedom degree damping vibration mechanical model, and analyzing related factors that influence the dynamic load error; (2) determining key factors that influence the dynamic load error; (3) pasting a resistance strain gauge on a position that is close to the tip of a crack of a CT specimen with a prefabricated crack to produce a specimen-strain gauge sensor; (4) statically calibrating the specimen-strain gauge sensor by a standard force sensor; (5) starting a fatigue testing machine to dynamically calibrate the specimen-strain gauge sensor, which has been statically calibrated in the step (4); and(6) according to static load and online measured crack length, carrying out bilinear interpolation on the data of dynamic calibration of the step (5) to obtain dynamic load measurement error; and carrying out error compensation based on the dynamic load measured value. The precision of the dynamic load online measurement of a fatigue testing machine is effectively improved.

Description

technical field [0001] The invention relates to the field of error compensation, in particular to an online compensation method for dynamic load errors of a resonance type fatigue testing machine. Background technique [0002] Fatigue damage is the main form of failure of mechanical parts. Since the fatigue fracture performance cannot be completely studied through effective theoretical methods, specific materials are used to conduct fatigue crack growth tests to explore the law of fatigue crack growth of parts and components. Product reliability and service life are of great significance. Since the performance of the fatigue testing machine directly affects the reliability and accuracy of the fatigue crack growth test results, the dynamic load error is a very important technical index when performing the fatigue crack growth test. At present, for the verification of the mechanical load of the fatigue test, the static calibration method is generally used, and the sensor can ...

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Problems solved by technology

[0004] In order to solve the problem that the existing static calibration method of fatigue testing machine and dynamic load error theory calibration compensation method have poor dynamic load compensation effects, the present invention provides a method with good error compensation effect, which can effectively improve the dynamic load measurement accuracy of fatigue testing machine Compensation Method for Maneuvering Load Error in Resonant Fatigue Test

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