Special issue. Preparation of new functional materials by dry process. Adhesion and internal stress measurement of thin films on solid surface.

The cut, a main preparing means of specimen, will cause a difference in stress distribution between thick plate and the specimen, so this article focuses on the topic of evaluating impact of the cut on stress measurement results. Firstly, the real surface stress distribution of the plate and specimen were determined by X-ray diffraction (XRD) and FEM. Secondly, according to the specimen dimension and machining procedure, the influence of the cut on internal stress measurement is obtained and compared with the FEM results. The conclusions are as follows: (1) the normal stress of cut plane steeply decreases and the stress gradient descends along with distance away from the cut. The range of distance is approximately one-thickness of specimen. (2) In order to obtain stable and reliable results, the plane size of specimen is taken three times larger than the thickness. (3) The milling processing of layer removal method (LRM) can change the surface stress state of specimen, but the machining effects on residual stresses can be removed by properly choosing milling parameters.

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On internal stress measurement and the mechanism of high temperature creep

Scripta Metallurgica ◽

10.1016/0036-9748(71)90094-9 ◽

1971 ◽

Vol 5 (6) ◽

pp. 475-478 ◽

Cited By ~ 70

Author(s):

P.W. Davies ◽

B. Wilshire

Keyword(s):

High Temperature ◽

Internal Stress ◽

Stress Measurement ◽

High Temperature Creep ◽

Temperature Creep ◽

Internal Stress Measurement

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Research of Correctness on Internal Stress Measurement in Aluminum Alloy Thick Plate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.3272 ◽

2011 ◽

Vol 383-390 ◽

pp. 3272-3278

Author(s):

Kai Liao ◽

Yun Xin Wu

Keyword(s):

Aluminum Alloy ◽

Internal Stress ◽

Thick Plate ◽

Measurement Problem ◽

Stress Measurement ◽

Experimental Conditions ◽

Total Uncertainty ◽

Layer Removal Method ◽

Simulation And Experiment ◽

Internal Stress Measurement

It’s necessary to research and analyze the correctness of internal stress measurement, in order to effectively deal with the measurement problem of stress field and rightly describe the distribution character of stress in aluminum alloy thick plate. Firstly, the total uncertainty of stress calculation in layer removal method (LRM) is determined by experimental error and model error, and less than ±10MPa, in which the accuracy of experiment is high. Secondly, in the integral calculation of LRM, a modified function is proposed by the multi-methods of simulation and experiment, and can compensate the deviation resulted from unpredictable error for experimental conditions. Then the multi-methods achieve the value of X-ray surface stress, simulation calculation and experimental results to consistent, the correctness of experimental calculation is enhanced. The research presents that the LRM can exactly describe distribution of internal stress in thick plate under special experiment conditions.

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