積層製造金屬與塑膠3D結構物件之超音波直接接合研究

Abstract

隨著科技發展，在同樣一件產品中，各部位會依照對應的應用方式，採取設計、材料與結構等考量進行組配，因此異種材質接合之應用顯得更為重要，其中在生活及工業上已被廣泛利用的材料，即為金屬與塑膠。 金屬與塑膠常見接合方式為利用黏著劑、機械式鎖附等，但黏著劑製程固化時間長、易老化，而螺絲機械式鎖附費時、耗工，且不利於大量製造，因此許多直接接合製程陸續被開發如射出成型、雷射熔接、摩擦攪拌與超音波熔接等，而接合機制不盡相同，其中以機械固錨理論，被認為是主要接著強度因素之一。 本研究基於機械固錨理論，利用超音波熔接製程方式進行金屬與塑膠接合，而金屬與塑膠皆採用積層製造方式製備，利用粉床式選擇性雷射熔融系統，於不鏽鋼金屬表面加法製造直徑500、600與700 μm的3D微細孔洞結構，藉由超音波熔接製程，與熔融沉積塑膠接合。實驗結果顯示，超音波熔接可於1 秒內完成接合製程，各參數試片皆成功接合，且熔接強度隨孔徑增加而提升，最大剪切強度17.63 MPa，等同於49%原塑膠材料強度。拉拔強度最高值則為熱輔助超音波熔接強度為16.51 MPa，等同於46%原塑膠材料強度，且拉拔強度最高達剪切強度85%。

Along with the development of science and technology, departmental parts are de-signed and assembled by its material and structure in one product. Therefore, the joining characteristics between these two dissimilar materials is an important issue. Among these materials, metals and plastics are mostly used in industrial applications. Metals and plastics are usually fastened by adhesive (glues) or mechanical tools. Nev-ertheless, current joining methods have some disadvantages, e.g. the volatile organic com-pounds and the difficulties of mass production due to a large quantity of mechanical inter-locking in manufacturing processes. For these reasons, several direct adhesion technologies have been developed, such as insert injection molding, laser welding, friction lap welding and ultrasonic welding. These technologies are affected by several different joining mech-anisms, however, micro mechanical interlocking is regarded as one of the major factor of the direct adhesion. The direct adhesion technologies based on micro mechanical interlocking were stud-ied and developed in this thesis. The direct joining of additive manufacturing 3D metal and plastic parts by ultrasonic welding were demonstrated. The 3D metal microstructures, which have different hole diameters of 500 μm, 600 μm, and 700 μm respectively, were fabricated by the selective laser melting (SLM) process, and the 3D plastics parts were manufactured by fused deposition modeling (FDM). According to the experiment results, all of parameter specimens were successfully joined within 1 sec. The joining strength gradually increased as the microstructures hole size, the highest shear bond strength were 17.63 MPa, and the highest plastic tensile strength were 17.63 MPa, its individually represented 49% and 46% of material ultimate tensile strength. Moreover, the tensile plastic strength was 85% of the shear bond strength.