泡沫材料是一種具高孔隙率、質量輕、隔音隔熱優良、吸能性佳之材料，至今已廣泛應用於各輕質結構工程中，然而，由於製造技術之限制，使得商業用泡沫材料微結構存在多種缺陷，進而降低其工程性質。本研究為改善傳統連通型與封閉型泡沫材料，於製作過程中不易控制其微結構缺陷，故採用球殼規則性堆疊的微結構排列方式，所製成球殼泡沫材料物理與工程性能可以更準確加以預測。本文將探討於單尺寸球殼與雙尺寸球殼兩種不同堆疊情況下，比較其於相同體積密度時，受單軸抗壓作用下其應力應變曲線的差異。首先，選用有限元素法套裝軟體ABAQUS進行數值分析，考慮剛版間球殼泡沫材料承受一單軸壓力作用，於剛版上施加一位移，數值分析求得其所承受應力之變化，進而獲得其應力應變曲線。數值分析結果發現，於相同相對密度條件下，採用雙尺寸球殼所製成泡沫材料之楊氏模數、降伏強度、應變能等力學性質，皆較單尺寸球殼所製成泡沫材料者提升許多。

Lightweight foam is a special kind of material with high porosity, good thermal insulation and excellent energy absorption. Foam has been widely used in lightweight structural engineering. However, due to the limitation in manufacturing, there are a variety of microstructural defects in commercially-available foams, thus reducing their engineering properties. In practice, hollow sphere foams are employed to replace the traditional foams with some microstructural defects resulting from production process. Because of the regularly-stacking microstructure of hollow sphere foams, their physical and engineering properties can be predicted more accurately. In the study, the difference in the uniaxial compressive stress-strain curves between the single-sized and dual-sized hollow sphere foams with the same relative density is discussed in detail. The commercially available finite element software ABAQUS is utilized here to conduct a series of numerical analyses. The stress-strain curves of hollow sphere foams between two rigid plates under uniaxial compression are obtained numerically. In running numerical analysis, a prescribed displacement is imposed on the rigid plates, the corresponding stresses on hollow sphere foams are calculated numerically. Furthermore, the resulting stress-strain curves of hollow sphere foams are presented and then compared to evaluate the effects of relative density and cell geometry. Numerical results show that the Young's modulus, yield strength and strain energy of dual-sized hollow sphere foams are consistently larger than those of single-sized hollow sphere foams with the same relative density.

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