Tue, 07 June, 2022
Dr Huan Wu and Dr Lei Xu, project leaders in TWI’s Advanced Manufacturing Technologies group, recently shared their knowledge at several international events, including a conference in China and an industrial workshop in Switzerland.
Firstly, Huan gave a talk for the online 2022 International Conference on Welding Materials and Technology, which was hosted by the Metallurgical Corporation of China, from 23-29 May 2022. The talk was on, ‘The Modelling of Manufacturing Processes,’ and detailed how manufacturing process simulations translate joining technologies and manufacturing processes into mathematical models to understand the relationships between processing conditions, heat transfer, stress development, deformation, and phase transformation. Understanding the effect of and optimising processing conditions (current, voltage, heating rates, soak times, weld sequence, etc) can be costly and time-consuming during the design stage, especially when only a trial-and-error experimental approach is available.
Lei also delivered a presentation at the conference on ‘Additive manufacturing and its applications’, highlighting TWI’s recent developments in industrialising the additive technologies. The presented work covers main aspects of technology development and industrialisation, from feasibility studies and business case proposals, numerical modelling and topology optimisation, and material and process selection, to finishing, heat treatments, inspection and testing, certification and validation, as well as relevant standards.
After this, Huan presented a paper at the 32nd International Ocean and Polar Engineering Conference (ISOPE) in Shanghai, China, held between 5-10 June, 2022. The paper, ‘Multi-physics Model to Assess Hydrogen Assisted Cold Cracking,’ investigated one of the most common forms of fabrication cracking in the welding of ferritic steels and how, with calibration to physical measurements, a model can minimise the number of welding trials undertaken and provide an enhanced understanding of the mechanisms and combinations of factors leading to HACC occurring.
Following her appearance in Shanghai, Huan will travel to Switzerland for the 8th International Workshop on Long-term Prediction of Corrosion in Nuclear Waste Systems (LTC), which is being held in Baden from 22-24 June, 2022. While attending the workshop, she will present on a ‘Probabilistic Model for the Prediction of the Distribution of Breaching Times of Carbon Steel Canisters.’ It is vital that nuclear waste canisters are able to resist a range of environmental condition, and this paper investigates the development of a probabilistic canister breaching model (PCBM), taking into account the effect of diverse sources of variability and uncertainty. These variables include the spatial and temporal variation in temperature and relative humidity in the repository, variation in the isostatic and asymmetric buffer swelling pressure and/or lithostatic pressure from convergence of the host rock, and variations in the canister material properties, as well as the size, shape, and location of defects associated with the final closure weld.
Huan has been with TWI since 2018, following the completion of her PhD in Mathematics and Statistics at the University of Warwick. She leads and supports our R&D projects in finite element analysis, additive manufacturing, solid mechanics, welding and joining process modelling, fracture and fatigue analysis, multi-physics and multi-scale modelling and data analysis.
Lei is a senior project leader in arc welding and processes after joining TWI in 2015. His background includes robotic arc welding and the associated inspection automation, process modelling and fixturing/tooling.