積層製造(AM)，通常稱為3D列印，是一種快速發展的製造技術，由於其能夠製造複雜的幾何形狀且易於定制，因此正在迅速取代傳統製造。波形彈簧在航空航天、汽車、石油和天然氣以及生物醫學等各種行業中具有潛在用途，在這些行業中，研究人員/工程師對此類彈簧的機械性能很感興趣。線圈滑動是積層製造波形彈簧軸向壓縮過程中注意到的重要現象之一。
本研究旨在研究波形彈簧線圈之間的可變摩擦接觸對能量吸收、剛度、承載能力和循環加載過程中的壓縮行為的影響。使用HP Multi Jet融合打印機設計和製造了九個具有不同輪廓的接觸波形彈簧，即正弦波、方形、凹面、凸面、V形和線圈表面的混合輪廓。隨著這項研究調查改變線圈形狀如何影響波形彈簧吸收能量的能力、剛度、承載能力以及加載-卸載期間的壓縮行為。設計了九種具有不同形狀線圈的接觸式波形彈簧，即方形、矩形、五角形、六角形、七角形、八角形、四角形、圓形（每個線圈4個波浪）和圓形（每個線圈6個波浪）。最多執行十個循環的壓縮測試，分析每個設計的機械性能和壓縮行為。正弦線圈顯示出最高的能量吸收，從第一個循環到第十個循環的能量損失最小，同時在本研究的所有設計中具有最低的剛度。
結果表明，這些可變的虛構接觸提高了設計的穩定性，因為線圈的滑動阻力增加並對機械性能產生重大影響，使研究人員能夠根據可變尺寸的負載/剛度要求，為不同的應用設計波形彈簧。實驗結果與有限元分析(FEA)進行了比較，有限元分析是使用相同的實驗測試邊界條件進行的，並且在承載能力和壓縮行為方面顯示出最小的變化。

Additive Manufacturing (AM), often known as 3D printing, is a fast-growing fabrication technology that is rapidly displacing traditional manufacturing due to its capacity to manufacture complex geometries with ease of customization. Wave springs have prospective uses in a variety of industries, including aerospace, automotive, oil and gas, and biomedical where researchers/engineers are interested in the mechanical properties of such springs. Slippage of coils is one of the significant phenomena that was noted during axial compression of additively manufactured wave springs. This study aims to investigate the effect of variable frictional contacts between the coils of wave spring on energy absorption, stiffness, load-bearing capacity, and compression behavior during loading- unloading. Nine contact wave springs with different profiles i.e., sine, square, concave, convex, V, and mixed profiles on the surface of coils were designed and fabricated using HP MultiJet fusion printer. Along with this research, it is investigated how changing the coil shape affects the wave spring's ability to absorb energy, its stiffness, its load-bearing capacity, and its compression behavior during loading-unloading. Nine contact type wave springs with various shapes of coils were designed i.e., square, rectangular, pentagonal, hexagonal, heptagonal, octagonal, quadro, circular (4 waves per coil), and circular (6 waves per coil). Compression testing was performed up to ten cycles to analyze the mechanical performance and compression behavior of each design. The sine profiled coils showed the highest energy absorption, with the minimum energy loss from the first to the tenth cycle while having the lowest stiffness among all the designs for this study. Furthermore, the results demonstrated that these variable fictional contacts improved the stability of the designs as the coil’s slippage resistance increased and has a significant impact on mechanical properties, allowing the researchers to design wave springs for different applications based on load/stiffness requirements having variable dimensions. Experimental results were compared with finite element analysis (FEA), which was performed using the identical boundary conditions of experimental testing and showed minimum variation in terms of load-bearing capacity and compression behavior.

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