本文選題：奧氏體不銹鋼 + 熱處理��； 參考：《華中科技大學(xué)》2015年碩士論文

【摘要】：在當(dāng)今鋼鐵冶煉生產(chǎn)中,連鑄技術(shù)被廣泛地應(yīng)用并且在不斷地發(fā)展,如何提高連鑄坯的質(zhì)量是人們?cè)絹碓疥P(guān)注的問題。為了提高板坯連鑄生產(chǎn)過程中連鑄坯的質(zhì)量,針對(duì)其工作性能的需求,已經(jīng)研制出了電磁攪拌用的設(shè)備——電磁攪拌輥(后文簡(jiǎn)稱“電攪輥”),內(nèi)部未凝固的鋼坯通過電攪輥時(shí),內(nèi)部的熔體被電磁攪拌力攪動(dòng)產(chǎn)生對(duì)流,從而細(xì)化晶粒。但無磁不銹鋼筒體這個(gè)電攪輥的關(guān)鍵核心部件的材料,依然依賴從國外進(jìn)口,國內(nèi)的材料基本無法實(shí)現(xiàn)其功能需求。因此,研制能夠滿足實(shí)際使用需求的高性能無磁不銹鋼筒體所用材料——無磁奧氏體不銹鋼,對(duì)于擺脫對(duì)進(jìn)口材料的依賴、降低生產(chǎn)成本具有非常重要的意義。本文主要對(duì)0Cr15Ni25Ti2MoAl VB奧氏體不銹鋼的熱處理工藝進(jìn)行研究。本文首先對(duì)奧氏體不銹鋼的成分、結(jié)構(gòu)進(jìn)行了介紹,然后闡述了本研究的理論基礎(chǔ),即各種合金元素在奧氏體不銹鋼組織中的作用機(jī)理,合金組織中常見的M23C6、MC等碳化物和金屬間化合物σ相、γ′相的結(jié)構(gòu)及其對(duì)材料性能的作用機(jī)理,以及相變強(qiáng)化、固溶強(qiáng)化、位錯(cuò)強(qiáng)化、沉淀強(qiáng)化、細(xì)晶強(qiáng)化等奧氏體不銹鋼強(qiáng)化的機(jī)理。接著基于所述理論基礎(chǔ),對(duì)0Cr15Ni25Ti2Mo Al VB奧氏體不銹鋼首先進(jìn)行了退火軟化處理,室溫進(jìn)爐,隨爐升溫至500℃后保溫4小時(shí),隨后取出空冷,此處理是為了使該材料便于機(jī)械加工。然后針對(duì)熱處理工藝——固溶時(shí)效,設(shè)計(jì)四因素三水平的正交實(shí)驗(yàn)方案,探究相對(duì)最合理的熱處理工藝參數(shù)。對(duì)經(jīng)過不同熱處理工藝方案的試樣,分別從硬度、屈服強(qiáng)度、抗拉強(qiáng)度、斷后伸長(zhǎng)率等力學(xué)性能數(shù)據(jù)進(jìn)行分析,得出結(jié)果:在固溶處理溫度950℃下保溫5h后油冷,時(shí)效處理溫度720℃下保溫14h后空冷的熱處理工藝參數(shù)方案為最佳,材料的硬度達(dá)到306HB,屈服強(qiáng)度σs達(dá)到839MPa,抗拉強(qiáng)度σb達(dá)到1086MPa,斷后伸長(zhǎng)率δ為28.1%,材料力學(xué)性能優(yōu)異,能夠滿足實(shí)際使用的需求。除此之外,用光學(xué)、電子顯微鏡對(duì)金相組織進(jìn)行觀察,晶體內(nèi)大量的析出γ′相[Ni3(Ti,Al)]及各種碳化物,對(duì)比各方案的微觀組織結(jié)構(gòu)的差異,并結(jié)合各方案的硬度和力學(xué)性能進(jìn)行分析,奧氏體不銹鋼組織中析出γ′相、碳化物等對(duì)材料性能的影響十分顯著。
[Abstract]:Nowadays, continuous casting technology is widely used in the production of iron and steel. How to improve the quality of continuous casting billet is more and more concerned. In order to improve the quality of continuous casting billet in the process of slab continuous casting, aiming at the demand of its working performance, An equipment for electromagnetic stirring has been developed-electromagnetic stirring roll (hereinafter referred to as "electric stirring roll"). When the inner unsolidified billet passes through the electric stirring roll, the melt inside is agitated by electromagnetic stirring force to produce convection, thus refining the grain size. However, the non-magnetic stainless steel cylinder, the key core component of the electric stirring roller, still depends on imported materials from abroad, and the domestic materials can hardly meet its functional requirements. Therefore, it is of great significance to develop the non-magnetic austenitic stainless steel, which can meet the practical application requirements, in order to get rid of the dependence on imported materials and reduce the production cost. The heat treatment process of 0Cr15Ni25Ti2MoAl VB austenitic stainless steel was studied in this paper. In this paper, the composition and structure of austenitic stainless steel are introduced at first, and then the theoretical basis of this study, that is, the action mechanism of various alloying elements in the microstructure of austenitic stainless steel, is described. The structure of carbides and intermetallic compounds 蟽 phase, 緯 'phase and their mechanism of action on the properties of materials, as well as phase transformation strengthening, solid solution strengthening, dislocation strengthening, precipitation strengthening, and so on, are common in alloy microstructure. Strengthening mechanism of austenitic stainless steel such as fine grain strengthening. Then, based on the theoretical basis, the 0Cr15Ni25Ti2Mo Al VB austenitic stainless steel was first annealed and softened, entered into the furnace at room temperature, kept for 4 hours after heating up to 500 鈩，

本文編號(hào)：1973133