Title: A PROCESS SIMULATION FRAMEWORK FOR IN-LINE CONTROL OF CONTINUOUS RESISTANCE WELDING

Authors: Stephen Atkinson, Scott Nesbitt, Reza Vaziri, Anoush Poursartip

DOI: 10.33599/nasampe/s.23.0089

Abstract: Thermoplastic composites are increasingly being utilized for aerospace applications where a significant benefit is the ability to implement fusion bonding techniques (welding). Continuous resistance welding (CRW), a promising form of fusion bonding, uses a movable apparatus which imposes electrical current and pressure to incrementally heat sections of a resistive implant placed between parts to fuse the interface. Precise temperature control at the bond line is necessary to avoid degradation of the polymer matrix, however, directly measuring the temperature history is invasive. Additionally, parameters such as boundary conditions, substructure properties, or part geometry may vary along the length of the weld. As such, we are developing physics-based simulation to control the input pressure, power, and speed in order to achieve optimal results. Development of the digital twin is founded upon an “MSTEP” framework which defines how the materials (M), shape (S), tooling (T), and equipment (E) interact to determine the process (P). Detailed finite element (FE) models are developed for thermal analysis based on the weld geometry, boundary conditions, and previously developed and validated melt/crystallization models for the thermoplastic matrix. Preliminary experimental CRW tests are presented to validate simulations and calibrate suitable control variables including external surface temperature and implant electrical resistance.
This project involves a collaboration with the National Research Council of Canada (NRC) and the German Aerospace Center (DLR). NRC has developed a gantry CRW apparatus for initial experimental testing, details of which are outlined in a companion paper in these conference proceedings. Additionally, DLR is adapting the welding system for robotic implementation on larger, more complex parts for full demonstration of the technology.

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Conference: SAMPE 2023

Publication Date: 2023/04/17

SKU: TP23-0000000089

Pages: 13

Price: $26.00