SrAl2O4:Eu,Ho/树脂应力发光薄膜在焊缝缺陷检测中的应用

采用高温固相法合成SrAl₂O₄∶Eu，Ho应力发光材料。XRD结果表明，所合成的样品较纯，掺杂离子并未改变基质材料的基体结构。将SrAl₂O₄∶Eu，Ho（SAOEH）应力发光粉末与树脂混合制备复合应力发光薄膜。光谱结果表明，薄膜的发光随着厚度的增加而增强；薄膜的SEM结果表明，SAOEH粉体颗粒均匀分散在树脂中。将应力发光薄膜应用于钢板焊缝处背面，应力测试结果表明薄膜应力发光先增强后减弱。当薄膜厚度为0.9 mm时，应力发光最强，且在焊缝处可得到较高的响应值。此外，在循环测试的过程中，应力发光薄膜可对焊板断裂实现实时响应，结合CCD相机可实现钢板焊缝检测的可视化，并对缺陷定位。

Application of SrAl2O4: Eu,Ho/Resin Mechanoluminescence Thin Film in Visualization Detection of Weld Seam Defects

Mechanoluminescence(ML) materials SrAl₂O₄:Eu,Ho(SAOEH) were prepared via solid state reaction. The XRD results show that the as-prepared sample is mostly monoclinic SrAl₂O₄ phase. The SAOEH powder was mixed with high elastic resin to prepare ML thin film. The photoluminescent intensity of the ML film increases following the increase of film thickness. The SEM results reveal that SAOEH ML particles disperse uniformly in the resin. In order to detect the weld seam defects, the SAOEH ML film was pasted in the backside of welding steel plate. It can be found that the ML intensity in the weld region is stronger than that in any other region. In addition, the ML intensity is enhanced following the increase of film thickness and reaches the strongest when the film thickness is 0.9 mm. Furthermore, the SAOEH film can be utilized to realize a real-time response to the fracture. Combining with CCD camera, the visual detection of steel weld and location of the defect region during the cyclic test can be realized.