【摘要】：通過高能噴丸方法在SUS430不銹鋼表面制備納米表層,利用X射線衍射(XRD)、熱分析(TGA)、掃描電鏡(SEM)及能譜(EDS)進(jìn)行測試,研究了納米表層在不同氣氛中的高溫氧化行為,并分析了表面自身納米化對SUS430不銹鋼耐氧化性能的影響。結(jié)果表明:納米表層在氧化初期氧化強(qiáng)烈,呈線性規(guī)律迅速增重,但達(dá)到鈍化的時間短,氧化膜薄且致密,厚度僅為原始表面氧化膜的1/4,使鈍化以后的氧化速率比原始表面低,總的氧化增重僅為原始表面的1/3,耐氧化性大大提高。其原因是表面自身納米化處理增加了表層的晶界面積,提高了氧化物的形核幾率,也為元素的擴(kuò)散提供了更多通道,因而促進(jìn)了Cr元素的選擇性氧化。在最表層形成的是疏松的富Fe氧化物,該層氧化物對耐氧化性的提高貢獻(xiàn)不大,在靠近基體的底層形成致密的富Cr氧化物,能很好地抵抗基體的進(jìn)一步氧化;納米表層比原始表面更容易形成連續(xù)的氧化膜,該氧化膜的內(nèi)應(yīng)力小,韌性好,與基體的結(jié)合力強(qiáng)。
[Abstract]:Nano-surface layer was prepared on the surface of SUS430 stainless steel by high energy shot peening. X-ray diffraction (XRD), thermal analysis (TGA), scanning electron microscope (SEM) and energy spectrum (EDS) were used to test. The oxidation behavior of nano-surface layer at high temperature in different atmosphere was studied, and the effect of surface self-nanomerization on the oxidation resistance of SUS430 stainless steel was analyzed. The results show that the oxidation of nano-surface layer is strong in the initial stage of oxidation, and the weight gain is linear, but the passivation time is short, the oxidation film is thin and dense, and the thickness is only 1 鈮，

本文編號：2488215