Effectofpriorhotrollingonmicrostructuresand-中华科技大学.DOC

麻田散鐵不銹鋼於硫酸漿砂中的沖磨腐蝕性能地圖 Erosion-corrosion Performance Maps of Martensitic Stainless Steel in Sulfuric Acid Slurry 藍翔耀溫東成H.Y. Lan D.C. Wen C.U. Chen 1中華技學院機械系副教授Department of Mechanical Engineering, China University of Science and Technology 2 Graduate Institute of Opto- Mechatronics, China University of Science and Technology 摘 要 在沖磨腐蝕環境中，沖蝕與腐蝕交互影響會加劇材料損耗，兩作用間的協同效應複雜且多變，並因沖蝕加速腐蝕、腐蝕加速沖蝕或腐蝕減緩沖蝕等方式衍生出不同的主控機制，本研究對麻田散鐵型不銹鋼SUS420J2在0.1M H2SO4溶液與碳化矽砂成的腐蝕環境中作不同沖磨角度(30°、60°、90°)與不同沖磨轉速(600rpm、800rpm、1000rpm)之沖磨腐蝕試驗後，探討沖磨腐蝕主控機制和沖磨腐蝕率與沖磨表面型態間的關聯，進而建構其沖磨腐蝕性能地圖。 研究結果顯示，材料在不同沖磨轉速和不同沖磨角度之累積重量損失均隨沖磨時間呈線性增，發生最大沖磨腐蝕率的試驗條件不必然是低沖擊角度(30°)，高沖磨轉速(1000rpm)，須視沖磨腐蝕主控機制而定。沖磨腐蝕主控模式在中高沖磨角度以腐蝕-沖蝕與沖蝕-腐蝕控制為主，且腐蝕與沖蝕間呈現相互加速的協同效應，在沖蝕與腐蝕的交互作用下，材料表面呈現出腐蝕生成物層被移除後的深腐蝕特徵，故有著較高的沖磨腐蝕率，在低沖磨角度則為腐蝕主控機制和加值效應，材料表面多為平坦的腐蝕生成物層及不規則的沖蝕孔穴，沖磨腐蝕率相對較低。關鍵字：不銹鋼，沖磨腐蝕，協同效應Abstract The damages mechanisms of materials in erosive and corrosive environment are complex and generally the measured material losses are higher than the sum of separate mass losses due the corrosion and erosion. The control modes of material loss are depended on the erosion-corrosion synergistic effects which are sensitive to material and test conditions such as impact angle and impact velocity. The aim of this work was to study the effect of impact angle (30(, 60(, 90() and impact velocity (600 rpm, 800 rpm, 1000 rpm) on the erosion-corrosion resistance of SUS420J2 stainless steel in sulfuric acid slurry. The findings related to the worn surfaces, material loss rate and erosion-corrosion behavior were evaluated and discussed. The results had shown that the accumulation weight losses were linearly increased with time. The maximum erosion-corrosion rates were neither in impact velocity of 1000 rpm nor at impact angle of 30(. And it is depended on the control mode of erosion- corrosion. The dominant mode of material loss was corrosion-erosion and erosion-corrosion for medium and high impact angles respectively and their synergism was positive.