The Integral Method for determining residual stresses involves making surface deformation measurements within a sequence of small increments of material removal depth. Typically, the associated matrix equation for solving the residual stresses within each depth increment is ill-conditioned. The resulting error sensitivity of the residual stress evaluation makes it essential that data measurement errors are minimized and that the residual stress solution method be as stable as possible. These two issues are addressed in this paper. The proposed method involves using incremental deformation data instead of the total deformation data that are conventionally used. The technique is illustrated using an example ESPI hole-drilling measurement.

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The developm.ent of recovery a.nd recrystallisation in cold rolled Al-4·5Mg-0·7 Mn (designated AA 5083) was analysed metall0!5.r~~hzcally, by measurz~g har.dness and e~ectrical conductivity, and by means of texture analysis. The precipitation state and the znztzal te~tu~e were varzed uszng a?proprz.ate pretreatments before cold rolling in order to study the influence of these parameters on kznetzcs and texture evolutlOn durzng deformation, recovery, and recrystallisation.Finally, the results obtained were compared with those obtainedfor conventionally produced material. MST/1960

The use of magnetic Barkhausen Noise Analysis (BNA) has been proven to be an effective tool for the non-destructive detection of microstructural anomalies in ferrous materials. Used as an in-process tool for the detection of grinding burn, heat treat defects and stresses, BNA is a quick comparative and quantitative alternative to traditional destructive methods. Applications of BNA as a quality control tool in gear production have existed for nearly two decades. This paper presents examples that demonstrate how BNA is used to evaluate changes in microstructural properties. Quantitative results correlate BNA test values to X-Ray diffraction values for the detection of changes in surface residual stress. Other quantitative analysis correlates BNA test values to surface hardness values for the detection of re-tempering burn. Qualitative results correlate BNA test values to acid etch patterns/colors for the detection of grinding burn defects. Robotically automated systems can test gear teeth and provide immediate feedback for process control and quality assurance.