An Gyubaek, Woo Wanchuck, Park Jeongung
Department of Naval Architecture and Ocean Engineering Chosun University, 61452, Gwangju, Korea.
Neutron Science Division, Korea Atomic Energy Research Institute, 34101, Daejeon, Korea.
J Nanosci Nanotechnol. 2019 Apr 1;19(4):2323-2328. doi: 10.1166/jnn.2019.16008.
The thickness of steel plates used for large structures has been increasing with the rapid increase in the size of welding structures. The growing capacity of large-scale ships, such as container ships, has led to an increase in the thickness and strength of steel plates for shipbuilding. The steel plate toughness and resistance to brittle fractures tend to decrease for thick plates because of the so-called thickness effect. This study uses 80-mm-thick steel plates and two welding processes (i.e., flux cored arc welding process and electron gas welding process) to produce full-thickness weld joints. The welding residual stress in both welded joints is measured to evaluate the brittle crack propagation path. This study aims to investigate the effect of welding variables on the crack arrest toughness and crack propagation path of thick steel-plate welds. The thick steel plate has a high possibility in brittle fracture. A quantitative analysis is conducted through a temperature-gradient ESSO test to clarify the effect of the welding variables on the flux cored arc welding and electron gas welding process joints of steel plates with 50 and 80 mm thicknesses. The welding residual stress is also measured to evaluate the welding residual stress effect in both welding processes on the brittle crack propagation path using a neutron science analysis.
随着焊接结构尺寸的迅速增大，用于大型结构的钢板厚度一直在增加。诸如集装箱船等大型船舶运力的不断提高，导致造船用钢板的厚度和强度增加。由于所谓的厚度效应，厚钢板的韧性和抗脆性断裂能力往往会降低。本研究采用80毫米厚的钢板和两种焊接工艺（即药芯焊丝电弧焊工艺和气体保护电弧焊工艺）来制作全厚度焊接接头。测量两种焊接接头中的焊接残余应力，以评估脆性裂纹扩展路径。本研究旨在探讨焊接变量对厚钢板焊缝止裂韧性和裂纹扩展路径的影响。厚钢板发生脆性断裂的可能性很高。通过温度梯度ESSO试验进行定量分析，以阐明焊接变量对厚度为50毫米和80毫米钢板的药芯焊丝电弧焊和气体保护电弧焊工艺接头的影响。还测量焊接残余应力，以使用中子科学分析评估两种焊接工艺中的焊接残余应力对脆性裂纹扩展路径的影响。
