Proprietary metal 3D printing is still relegated to relatively expensive systems that have been constructed over years of expensive trial-and-error to obtain optimum 3D printing settings.Low-cost open-source metal 3D ...Proprietary metal 3D printing is still relegated to relatively expensive systems that have been constructed over years of expensive trial-and-error to obtain optimum 3D printing settings.Low-cost open-source metal 3D printers can potentially democratize metal additive manufacturing;however,significant resources are required to redevelop optimal printing parameters for each metal on new machines.In this study,the particle swam optimization(PSO)experimenter,a free and open-source software package,is utilized to obtain the optimal printing parameters for a tungsten inert gas-based metal open source 3D printer.The software is a graphical user interface implementation of the PSO method and is designed specifically for hardware-in-loop testing.It uses the input of experimental variables and their respective ranges,and then proposes iterations for experiments.A custom fitness function is defined to characterize the experimental results and provide feedback to the algorithm for low-cost metal additive manufacturing.Four separate trials are performed to determine the optimal parameters for 3D printing.First,an experiment is designed to deposit and optimize the parameters for a single line.Second,the parameters for a single-layer plane is optimized experimentally.Third,the optimal printing parameters for a cube is determined experimentally.Fourth,the line optimization experiment is revised and reconducted using different shield gas parameters.The results and limitations are presented and discussed in the context of expanding wire arc additive manufacturing to more systems and material classes for distributed digital manufacturing.展开更多
Based on the symmetric re-entrant honeycomb(S-RH)structure with negative Poisson’s ratios,a novel asymmetric and rotatable re-entrant honeycomb(AR-RH)structure was proposed.Both the S-RH structure and AR-RH structure...Based on the symmetric re-entrant honeycomb(S-RH)structure with negative Poisson’s ratios,a novel asymmetric and rotatable re-entrant honeycomb(AR-RH)structure was proposed.Both the S-RH structure and AR-RH structure were produced by the 3D printing technology.Through experimental test and finite element simulation,the deformation mechanism and energy absorption characteristics of the AR-RH structure and the S-RH structure with negative Poisson’s ratios at different impact velocities were compared.The experimental test and finite element simulation results show that the novel AR-RH structure with negative Poisson’s ratios has stronger energy absorption capacity than the S-RH structure,and it has been verified that the rotatability of AR-RH can indeed absorb energy.Furthermore,the degree of asymmetry of the AR-RH structure was discussed.展开更多
文摘Proprietary metal 3D printing is still relegated to relatively expensive systems that have been constructed over years of expensive trial-and-error to obtain optimum 3D printing settings.Low-cost open-source metal 3D printers can potentially democratize metal additive manufacturing;however,significant resources are required to redevelop optimal printing parameters for each metal on new machines.In this study,the particle swam optimization(PSO)experimenter,a free and open-source software package,is utilized to obtain the optimal printing parameters for a tungsten inert gas-based metal open source 3D printer.The software is a graphical user interface implementation of the PSO method and is designed specifically for hardware-in-loop testing.It uses the input of experimental variables and their respective ranges,and then proposes iterations for experiments.A custom fitness function is defined to characterize the experimental results and provide feedback to the algorithm for low-cost metal additive manufacturing.Four separate trials are performed to determine the optimal parameters for 3D printing.First,an experiment is designed to deposit and optimize the parameters for a single line.Second,the parameters for a single-layer plane is optimized experimentally.Third,the optimal printing parameters for a cube is determined experimentally.Fourth,the line optimization experiment is revised and reconducted using different shield gas parameters.The results and limitations are presented and discussed in the context of expanding wire arc additive manufacturing to more systems and material classes for distributed digital manufacturing.
基金This work is supported by the State Key for Strength and Vibration of Mechanical Structures of Xi’an Jiaotong University(No.SV2018-KF-32)the Natural Science Foundation of Guangdong Province of China(2020A1515011064).
文摘Based on the symmetric re-entrant honeycomb(S-RH)structure with negative Poisson’s ratios,a novel asymmetric and rotatable re-entrant honeycomb(AR-RH)structure was proposed.Both the S-RH structure and AR-RH structure were produced by the 3D printing technology.Through experimental test and finite element simulation,the deformation mechanism and energy absorption characteristics of the AR-RH structure and the S-RH structure with negative Poisson’s ratios at different impact velocities were compared.The experimental test and finite element simulation results show that the novel AR-RH structure with negative Poisson’s ratios has stronger energy absorption capacity than the S-RH structure,and it has been verified that the rotatability of AR-RH can indeed absorb energy.Furthermore,the degree of asymmetry of the AR-RH structure was discussed.