Methodological Approach and Software for Assessing Loads, Defects and Degradation of Mechanical Characteristics in Structural Materials, Based on Processing Experimental Data

Authors: Chernyatin A.S., Razumovskiy I.A. Published: 14.09.2017
Published in issue: #5(116)/2017  

DOI: 10.18698/0236-3941-2017-5-64-74

Category: Mechanical Engineering and Machine Science | Chapter: Inspection and Diagnostics in Mechanical Engineering  
Keywords: finite element method, optical digital methods of displacement investigation, indentation method, optimisation problem, load and defect assessment

The article deals with the basics of an experimental computational method to assess of loads, defects and deformation characteristics of materials based on mathematically processing experimentally obtained displacement or strain fields caused by exposing the object under consideration to certain factors (varying the load, drilling a small hole, indentation etc.). We base our method on determining the parameters desired so as to minimise the objective function describing the discrepancy between considerable arrays of experimental data and the results of a series of finite element computations aimed at solving model problems. We supply example solutions of model problems dealing with determination of loads and dimensions of surface and subsurface defects on full scale objects, as well as with simultaneously determining existing stresses and the yield point in a material by means of processing residual displacement fields caused by using a spherical indenter to the load workpiece zone under consideration and subsequent unloading


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