Romanowicz Paweł J, Szybiński Bogdan, Wygoda Mateusz
Institute of Machine Design, Cracow University of Technology, ul. Warszawska 24, 31-155 Cracow, Poland.
Department of Product Technology and Ecology, College of Management and Quality Sciences, Cracow University of Economics, ul. Rakowicka 27, 31-510 Cracow, Poland.
Materials (Basel). 2020 Aug 5;13(16):3460. doi: 10.3390/ma13163460.
The paper presents the assessment of the possibility and reliability of the digital image correlation (DIC) system for engineering and scientific purposes. The studies were performed with the use of samples made of the three different materials-mild S235JR + N steel, microalloyed fine-grain S355MC steel, and high strength 41Cr4 steel subjected to different heat-treatment. The DIC studies were focused on determinations of dangerous zones with large stress concentrations, plastic deformation growth, and prediction of the failure zone. Experimental tests were carried out for samples with different notches (circular, square, and triangular openings). With the use of the DIC system and microstructure analyses, the influence of different factors (laser cutting, heat treatment, material type, notch shape, and manufacturing quality) on the material behavior were studied. For all studied cases, the stress concentration factors (SCF) were estimated with the use of the analytical formulation and the finite element analysis. It was observed that the theoretical models for calculations of the influence of the typical notches may result in not proper values of SCFs. Finally, the selected results of the total strain distributions were compared with FEM results, and good agreement was observed. All these allow the authors to conclude that the application of DIC with a common digital camera can be effectively applied for the analysis of the evolution of plastic zones and the damage detection for mild high-strength steels, as well as those normalized and quenched and tempered at higher temperatures.
本文介绍了用于工程和科学目的的数字图像相关（DIC）系统的可能性和可靠性评估。研究使用了由三种不同材料制成的样品——低碳S235JR+N钢、微合金细晶粒S355MC钢和经过不同热处理的高强度41Cr4钢。DIC研究的重点是确定应力集中大的危险区域、塑性变形的增长以及失效区域的预测。对具有不同缺口（圆形、方形和三角形开口）的样品进行了实验测试。通过使用DIC系统和微观结构分析，研究了不同因素（激光切割、热处理、材料类型、缺口形状和制造质量）对材料行为的影响。对于所有研究案例，使用解析公式和有限元分析估算了应力集中系数（SCF）。观察到计算典型缺口影响的理论模型可能会导致SCF值不正确。最后，将总应变分布的选定结果与有限元分析结果进行了比较，观察到良好的一致性。所有这些使作者能够得出结论，使用普通数码相机的DIC可以有效地应用于分析低碳高强度钢以及在较高温度下正火、淬火和回火钢的塑性区演变和损伤检测。
