3D Reconstruction and Quantitative Analysis of Hot Cracking by Metallographic Extraction
摘要
As weldability and printability challenges continue to be addressed, accurate and precise evaluation of cracking phenomena are crucial to ensure fitness for service. Non-destructive techniques such as x-ray computed tomography (XCT) are currently used when attempting to evaluate cracks and other defects in a 3-dimensional environment. However low interfacial distances and high aspect ratios limit the detectability of cracking present. This work seeks to pursue the valuable information only available by analyzing a 3D space, while increasing reliability by collecting information through destructive testing. A semi-automated pipeline handles serially collected micrographs to reconstruct cracks and other features within a specimen. Cracks are then segmented into individually identifiable features for quantitative analysis. The pipeline provides crack specific information such as geometry, abundance, orientation, and interconnection. All reconstruction and analysis are designed to be material and sample geometry agnostic. User inputs are minimized to the initial image stack acquisition and limited parameter optimization accounting for variation in image collection methodologies. The process is demonstrated on a transverse Varestraint weldability test which has been serially polished and then reconstructed for analysis. Established variables for the test describing the number and morphology of cracks are calculated and exported in an accessible format. While discussing the implementation of the process on this specific case, adaptability to additive manufacturing and other weldability tests is emphasized.