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Classical mechanics courses are taught to most engineering disciplinary undergraduate students. Due to the recent advancements of multiscale analysis and practice, necessary reforms need to be investigated and explored for classical mechanics courses to address the materials’ mechanics behaviors across multiple length scales. This enhanced understanding is needed for engineering students to consider materials more broadly. This paper presents a recent effort for the development of a multiscale materials and mechanics experimentation (M3E) module that can be potentially implemented in undergraduate mechanics courses, including Statics, Dynamics, Strength of Materials, and Design of Mechanical (Machine) Components. The developed education module introduces the concepts of multiscale materials behavior and microstructures in the form of micro and macro-scales. At the micro-scale, both 3D printed aluminum and cold-rolled aluminum samples were characterized using scanning electron microscope. Microstructures, including grains, grain boundaries, dislocation, precipitates, and micro-voids, were demonstrated to students. At the macro-scale, experiments following ASTM standards were conducted and full strain fields carried by all the samples were analyzed using digital image correlation method. The experimental data were organized and presented to the students in the developed M3E module. The implementation of the developed module in undergraduate mechanics classes allows students to not only visualize materials behavior under various load conditions, but also understand the reasons behind classical mechanics properties. To assess the effectiveness of the developed M3E education module, an evaluation question was developed. Students are required to classify key mechanics, materials, and processing concepts at both micro and macroscales. More than 40 fundamental concepts and keywords are included in the tests. The study outcomes and effectiveness of the M3E education module will be reported in this paper. 

This paper presents the development and preliminary implementation of a multi-scale material and mechanics education module to improve undergraduate solid mechanics education. We experimentally characterize 3D printed and conventional wrought aluminum samples and collect structural images and perform testing at the micro- and macro- scales. At the micro-scale, we focus on the visualization of material’s grain structures. At the macro-scale, standard material characterization following ASTM standards is conducted to obtain the macroscopic behavior. Digital image correlation technology is employed to obtain the two-dimensional strain field during the macro-scale testing. An evaluation of student learning of solid mechanics and materials behavior concepts is carried out to establish as baseline before further interventions are introduced. The established multi-scale mechanics and materials testing dataset will be also used in a broad range of undergraduate courses, such as Solid Mechanics, Design of Mechanical Components, and Manufacturing Processes, to inform curricular improvement. The successful implementation of this multi-scale approach for education is likely to enhance students’ understanding of abstract solid mechanics theories and establish links between mechanics and materials concepts. More broadly, this approach will assist advanced solid mechanics education in undergraduate engineering education throughout the country. 

This paper presents the development and preliminary implementation of a multi-scale material and mechanics education module to improve undergraduate solid mechanics education. We experimentally characterize 3D printed and conventional wrought aluminum samples and collect structural images and perform testing at the micro- and macro- scales. At the micro-scale, we focus on the visualization of material’s grain structures. At the macro-scale, standard material characterization following ASTM standards is conducted to obtain the macroscopic behavior. Digital image correlation technology is employed to obtain the two-dimensional strain field during the macro-scale testing. An evaluation of student learning of solid mechanics and materials behavior concepts is carried out to establish as baseline before further interventions are introduced. The established multi-scale mechanics and materials testing dataset will be also used in a broad range of undergraduate courses, such as Solid Mechanics, Design of Mechanical Components, and Manufacturing Processes, to inform curricular improvement. The successful implementation of this multi-scale approach for education is likely to enhance students’ understanding of abstract solid mechanics theories and establish links between mechanics and materials concepts. More broadly, this approach will assist advanced solid mechanics education in undergraduate engineering education throughout the country. 

An electric field‐assistedin situdispersion of multiwall carbon nanotubes (MWCNTs) in polymer nanocomposites, fabricated through stereolithography three‐dimensional (3D) printing technique, was demonstrated. The introduction of MWCNTs increased the elasticity modulus of the polymer resin by 77%. Furthermore, the use of an electric field forin situMWCNT dispersion helped improving the average elongation at break of the samples with MWCNTs by 32%. The electric field also increased the ultimate tensile strength of the MWCNT reinforced nanocomposites by 42%. An increase of over 20% in the ultimate tensile strength ofin situdispersed MWCNT nanocomposites over the pure polymer material was observed. Finally, it was demonstrated that the magnitude and direction of the electrical conductivity of MWCNT nanocomposites can be engineered through the application ofin situelectric fields during 3D printing. An increase of 50% in the electrical conductivity was observed when MWCNTs were introduced, while the application of the electric field further improved the electrical conductivity by 26%. The presented results demonstrated the feasibility of tuning both electrical and mechanical properties of MWCNT reinforced polymer nanocomposites usingin situelectrical field‐assisted 3D printing. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47600.