碳纖無電鍍銅鎳製程參數對鋁基複合材料(A356/Cf)性質之影響

Abstract

本實驗係以擠壓鑄造法(Squeeze Casting)製作鋁基複合材料，基地為 A356鑄造用鋁合金，補強材則採用PAN Precursor的長纖碳纖維。在預形 體的製作上，則採用碳纖疊層的方式，如此碳纖可以排列得較筆直。為了 防止界面反應物Al4C3的生成及改善碳纖與鋁基界面的潤濕性不好的問題 ，我們將碳纖表面經過鍍鎳及磷酸皮膜處理，實驗中發現碳纖經過鍍鎳處 理後與鋁基有較好的界面性。因此，實驗注重在鍍鎳製程參數對碳纖與基 地之界面性質的影響。主要製程參數為改變鍍浴中次磷酸鈉含量、PH值及 溫度。從不同的碳纖鍍鎳製程參數之複材的熱疲勞性質比較得知，鍍浴中 含20g/l的次磷酸鈉，PH=5且保持溫度在85℃環境下所得的鎳膜與鋁基及 碳纖有較好的界面性質。而從拉伸的性質測試也顯 示碳纖鍍鎳後有較大 的抗拉強度。 In this study, aluminum based metal matrix composites (MMCs) are fabricated by squeeze casting. In the MMCs, the matrix is A356 aluminum alloyand the reinforcement is carbon continuous fibers made of PAN precursor. The fabrication of preform is made by layer-stacked method,so the fibers distribute more straightly.In order to prevent the formation of reactions Al4C3 and to improve the poor wettabilitybetween fibers and matrix,the electroless nickel (EN) plating and acid phosphate binder were coated on carbon fibers.We found that the fibers coatedNi-P have good interface bonding with aluminum matrix.Therefore,the experiment emphasizes on the effect of electroless nickel plating parameters on interface between fibers and matrix. The main parameters vary on the content of sodium hypophosph ite、 PH value and temperature in EN solutions.To compare withdifferent composites by thermal cycles test,we found that the EN plating deposits of which solution contains 20g/L sodium hypophosphite at ph=5 and 85℃ obtain good interface bonding with carbon fibers and aluminum matrix.The tensile test also shows that the composites whose fibers coated Ni-P have higher tensile stress.