Detection method of residual stress

Abstract

The invention discloses a detection method of residual stress, and particularly relates to detection on a plastics product. The detection method comprises the steps of immersing a product to be detected in a corrosion solution, and taking the product to be detected out and detecting whether a residual stress reaction occurs when the immersing time reaches an immersing time set value, wherein if the residual stress reaction does not occur, the product to be detected is qualified. The corrosion solution can be prepared by mixing carbon tetrachloride and normal octane according to the volume ratio of 1:1, or by mixing methylbenzene and normal propyl alcohol according to the volume ratio of 1:3; the immersing time is obtained by processing immersing time within which the stress reaction occurs during pre-detection on products in the same batch, and under the residual stress reaction, the surface of a plastic product cracks or powdery particulate materials are formed on the surface of the plastic product due to corrosion.

Description

technical field [0001] The invention relates to the field of measurement, in particular to a method for detecting residual stress. Background technique [0002] In the injection molding process of engineering plastics, during the process of filling the mold and maintaining pressure, the melt flow produces flow stress and molecular orientation, and the temperature distribution inside and outside the product is uneven during the cooling process, thermal expansion and contraction are limited, and at the same time The action of heat and force, resulting in residual stress. In the use of injection molded products, temperature, humidity, heat, etc. will induce residual stress release. This slow stress release will cause tiny cracks in the part of the product, which not only reduces the mechanical strength, but also leads to the risk of local accelerated oxidation, which may eventually lead to functional failure of the injection molded product. For this reason, it is necessary to...

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Problems solved by technology

[0004] In view of the problems existing in the residual stress detection method of plastic products in the prior art, the purpose of the present invention is to propose a detection method to solve at least one of the above problems

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