Evaluation of Residual Stresses Induced by High Speed Milling Using an Indentation Method

Felipe Díaz, Claudio Mammana, Armando Guidobono

Departamento de Ingeniería Electromecánica—Departamento de Ingeniería Industrial, Facultad Regional Rafaela,.
División Metrología Dimensional, Centro Regional Rosario (INTI), Rosario, Argentina.

DOI: 10.4236/mme.2012.24019                

Abstract

In this work, a recently developed method based on the change of distance between collinear indents is used to evaluate different states of residual stress, which were generated in samples of AA 6082-T6 and AA 7075-T6 aluminium alloys milled at high speed. One of the advantages of this method, which needs a universal measuring machine, is not requiring neither the use of specific equipment nor highly skilled operators. Also, by integrating an indentation device to the mentioned machine, the absolute error of measurement can be reduced. In results obtained in samples subjected to different cutting conditions it is observed a correlation between the stress values and the depth of cut, showing the AA 6082-T6 alloy higher susceptibility to be stressed. Furthermore, the high sensitivity of the method allowed detecting very small differences in the values reached by different normal components in the zones corresponding to climb and conventional cutting. It is important to note that these differences were similar for both evaluated alloys. Finally, the directions associated with the principal components of residual stress, where maximum local plastic stretching occurs, were found to be strongly dependent on the rolling direction prior to machining.

Keywords

Residual Stresses; High Speed Milling; Indentation Methods; Aluminium Alloys; Principal Directions

Conflicts of Interest

The authors declare no conflicts of interest.

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