【摘要】：作為6%Mo的超級(jí)奧氏體不銹鋼,254SM0具有優(yōu)異的耐腐蝕性能,廣泛地應(yīng)用于高氯離子環(huán)境。254SM0較高的合金元素含量,特別是高的Mo含量,在賦予其優(yōu)異耐蝕性能的同時(shí),也導(dǎo)致有害析出相易于產(chǎn)生,材料容易發(fā)生高溫氧化,難于熱加工。 本文主要采用力學(xué)試驗(yàn)方法、微觀組織分析、Gleeble熱模擬、特定環(huán)境的腐蝕分析等方法對(duì)254SMO的相析出行為及其對(duì)力學(xué)、耐蝕性能、熱變形行為的影響,以及抗氧化性能進(jìn)行了研究,并對(duì)其機(jī)理進(jìn)行探討,推薦了254SM0最佳的熱處理和熱加工工藝參數(shù)。為國內(nèi)254SMO及其他超級(jí)奧氏體不銹鋼的研究和下一代超級(jí)奧氏體的開發(fā)提供了一定的數(shù)據(jù)和理論支持。本文主要研究結(jié)果和結(jié)論為： 1、254SMO(?)出相的類型較為復(fù)雜,Mo含量均較高,其主要的析出相為σ相和χ相,也含有少量的其他相,如M23C6, Cr2N, Laves相等；σ相和χ相的最高析出溫度分別達(dá)到了1150。C和1050℃。通過應(yīng)力松弛方法獲得了σ相和χ相的析出曲線,它們對(duì)應(yīng)的析出峰分別為975。C和875。C。 2、有害相的析出對(duì)254SMOI的性能影響顯著,它們將顯著降低材料的塑韌性及耐蝕性能。1150℃和1100℃沉淀的大塊析出相,對(duì)應(yīng)力腐蝕性能的影響明顯；當(dāng)固溶處理溫度達(dá)到1200℃左右時(shí),254SMO具有較好的組織、力學(xué)和耐蝕性能。 3、254SMO的最佳熱塑性溫度區(qū)間較窄,約為1200-1250。C；其熱變形過程軟化方式為動(dòng)態(tài)再結(jié)晶,動(dòng)態(tài)再結(jié)晶機(jī)制為晶界遷移形核方式,動(dòng)態(tài)再結(jié)晶激活能為508.7kJ,同時(shí)計(jì)算了254SM0的熱壓縮變形方程。 4、254SMO(?)氧化性能較差,且對(duì)溫度敏感性強(qiáng)。材料高溫生成的氧化物主要為Mo氧化物,其次是Fe304人Fe203型氧化物；其中,Mo氧化物是導(dǎo)致材料抗氧化性能差的主要原因,而Fe203型氧化物在1050。C和1100℃的高溫分解促使氧化加劇。
[Abstract]:As a super austenitic stainless steel of 6%Mo, 254SM0 has excellent corrosion resistance and is widely used in high chloride ion environment. The higher content of alloying elements, especially the high content of Mo, gives 254SM0 excellent corrosion resistance. It also leads to the formation of harmful precipitates, the high temperature oxidation of materials and the difficulty of hot working. In this paper, mechanical test method, microstructure analysis, Gleeble thermal simulation, corrosion analysis of specific environment and other methods are used to analyze the precipitation behavior of 254SMO phase and its influence on mechanical, corrosion resistance and thermal deformation behavior. The oxidation resistance was studied and the mechanism was discussed. The best parameters of heat treatment and hot working for 254SM0 were recommended. It provides some data and theoretical support for the research of 254SMO and other super austenitic stainless steels and the development of the next generation super austenite. The main results and conclusions of this paper are as follows: 1254SMO (?) The main precipitated phases are 蟽 phase and 蠂 phase, and there are a few other phases, such as M23C6, Cr2N, Laves are equal, the highest precipitation temperature of 蟽 phase and 蠂 phase is 1 150.C and 1050 鈩，

本文編號(hào)：2371716