微機械固錨對塑膠/金屬直接接合強度影響之研究

Abstract

各種材料的物性都有其優點與缺點，隨著科技進步，單獨使用一種材料往往無法滿足近代之產品需求，因此異種材質接合之應用，特別是金屬與塑膠間的接合為目前各產業相當重要的課題。 以接著劑黏合為最泛用的異種材質接合方法，但使用接著劑並不環保且製程所需固化時間長，並不符合經濟效益，因此許多塑膠/金屬直接接合技術近十年間被陸續開發出來取代結著劑黏合製程，如射出成型、熱壓接合、雷射焊接、超音波焊接、摩擦攪拌焊等等，這些塑膠/金屬直接的接合機制不盡相同，其中微觀機械固錨被認為是最主要的因素之一。 本研究立基於微機械固錨理論，針對直接結合的各種課題進行探討並提出改善建議，第一部分以射出成型直接結合ABS與PBT+30%GF在具微結構之A5052試片上，實驗中裝設了模內加熱裝置單獨加熱金屬件，金屬件溫度升溫至130°C時，PBT+30%GF即可接合於陽極、微弧氧化與雷射試片上，但ABS只能與雷射加工試片成功結合。第二部分則是利用金屬表面微結構實現了低能量需求之超音波直接接合技術，得以在一秒內，以低於100J的焊接能結合ABS於A5052上。另外，一預測微機械固錨之剪切理論強度的方法被推導出來，二種接合方法製備之ABS/A5052雷射試片剪切強度皆接近理論值，實驗中射出試片最高剪切強度約14MPa，達塑膠材料本身強度的36%；超音波試片最高剪切強度約11MPa，達塑膠材料本身強度的28%。

Every material has its unique material properties, which can bring benefits or shortcomings. As advances of technologies, use of only one particular material very often cannot meet the demand of products. Thus, joining of dissimilar materials, especially between metal and plastic, has become a key issue in many industries. Industrial joining of dissimilar materials is generally performed by using adhesive bonds. Nevertheless the usage of adhesives is not environmentally friendly and takes long curing time. Several direct adhesion technologies have been developed, such as insert injection molding, hot pressing, laser welding, ultrasonic welding, and friction lap welding. These technologies were achieved by several different joining mechanisms, however, micro mechanical interlocking is considered as one of the major factor of the direct adhesion. The direct adhesion technologies based on micro mechanical interlocking were studied and developed in this thesis. In the first part, ABS and PBT+30%GF parts were formed and joined on micro-structured A5052 parts by injection molding method. An in-mold heating device was used to heat the metal insert independently. The PBT+30%GF could be joined onto the anodized, PEO, laser treated metal insert when the metal insert heated over 130°C. However, the ABS part could only joined onto laser specimen. In the second part, a low energy demand ultrasonic direct adhesion technology was carried out by the laser micro structure on the metal surface. The ABS parts were joined onto A5052 laser specimens by weld energy lower than 100J in 1sec. A method to predict the shear bond strength of micro-mechanical interlocking was established, and the shear bond strength of ABS/A5052 laser structured specimens were near the theoretical strength. The highest shear bond strength of injection molding was 14MPa, which was 36% of the plastic tensile strength. The highest shear bond strength of ultrasonic direct adhesion was 11MPa, which was 28% of the plastic tensile strength.