無電鍍鎳及電弧沉積Cr-N-O鍍膜對ADI耐蝕性之影響

Effects of Electroless Nickel and Cr-N-O Arc-coatings on Corrosion Resistance of ADI

呂佳鴻(Jia-hong Lu)

指導教授 ： 許正勳

大同大學/工程學院/材料工程學系所/碩士(2007年)

摘要

沃斯回火球墨鑄鐵(Austempered ductile iron, ADI)，為將球墨鑄鐵經由沃斯回火熱處理而得，所得之具高強度、耐磨耗及低成本等優點的材料，本研究主要針對因受限ADI的回火溫度(小於450℃)，不得對其材料用傳統的表面熱處理改善表面性質，故而選用在現今工業界正蓬勃發展的真空鍍膜技術，物理氣相沉積(Physical vapor deposition, PVD)中的陰極電弧沉積(Cathodic arc deposition, CAD)來對ADI材料表面進行披覆薄膜。此研究材料表面決定披覆CrN及改變氮氣和氧氣流量所形成之Cr(N,O)/CrN兩種硬質薄膜，針對單層膜與複合鍍膜的機械性質和耐蝕性作討論，並且為了鍍膜和基材應力差過大而預先披覆一層無電鍍鎳。
結果顯示，不論是單層膜或複合膜皆有效強化ADI的表面硬度及耐腐蝕，然而附著性不佳，若是披覆在有經無電鍍鎳的ADI上，不僅附著性良好，防蝕性也大為提升。

關鍵字

沃斯回火球墨鑄鐵 ； 陰極電弧沉積 ； CrN ； 耐蝕性 ； 無電鍍鎳 ； 硬度 ； 附著性

並列摘要

Austempered ductile iron (ADI) is a material with high tensile strength, wear resistance, fatigue resistance and low cost. Generally, the range of austempering temperature of ADI is Ms ~ 450℃, the traditional heat treatment at high temperature for case hardening is not available to ADI. This research used the cathodic arc deposition (CAD) to deposit CrN and Cr(N,O)/CrN films by controlling the ratio of nitrogen and oxygen flow, and test the mechanical properties, corrosion behaviors of ADI. Avoid large difference of stress between film and substrate, electroless nickel (ENi) is used to deposit on ADI beforehand. The results showed that the hardness and corrosion resistance both better than uncoated ADI, but adhesion between films and ADI is not good. ADI with ENi treatment not only can improve adhesion certainly corrosion resistance also can get rise.

並列關鍵字

Austempered ductile iron ； Cathodic arc deposition ； CrN ； corrosion resistance ； electroless nickel ； hardness ； adhesion

參考文獻

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