本文關(guān)鍵詞： 控軋控冷 Mn-Ti型高強(qiáng)鋼 拉伸性能 沖擊韌性 Gleeble-3800　出處：《中北大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：鋼鐵產(chǎn)業(yè)是我國國民經(jīng)濟(jì)的支柱性產(chǎn)業(yè),目前我國鋼鐵產(chǎn)業(yè)正處于化解產(chǎn)能過剩的關(guān)鍵時(shí)期,另外國內(nèi)外眾多領(lǐng)域用鋼也提出了更高強(qiáng)度、更好塑性以及一定韌性和良好焊接性的要求�？剀埧乩涔に囎鳛�21世紀(jì)一項(xiàng)新技術(shù),控軋控冷技術(shù)下低碳微合金化高強(qiáng)度鋼不僅在改善鋼材的綜合性能方面取得了明顯的效果,在鋼鐵生產(chǎn)上得到廣泛應(yīng)用,而且控軋控冷技術(shù)在減少能源消耗發(fā)展制造綠色鋼鐵材料發(fā)揮了重要作用,是目前各國鋼鐵學(xué)者的研究熱點(diǎn)。本文主要研究了控軋控冷工藝下低碳微合金Mn-Ti型鋼在室溫拉伸變形、低溫沖擊及熱壓縮狀態(tài)下,得到實(shí)驗(yàn)鋼在不同實(shí)驗(yàn)參數(shù)下的微觀組織和力學(xué)性能,分析其微觀組織的演變過程,及組織對實(shí)驗(yàn)鋼力學(xué)性能的影響,結(jié)合實(shí)驗(yàn)鋼具體的使用條件和要求,為鋼鐵實(shí)際生產(chǎn)過程控軋控冷工藝參數(shù)制定提供理論依據(jù),具體研究內(nèi)容如下:(1)研究Mn-Ti型實(shí)驗(yàn)鋼分別在20℃/s、2℃/和0.2℃/s不同冷卻速度下室溫拉伸變形過程微觀組織演變及抗拉強(qiáng)度,確定了實(shí)驗(yàn)鋼在冷卻速度下的相變機(jī)制,得到Mn-Ti型實(shí)驗(yàn)鋼隨著冷卻速度增加,屈服強(qiáng)度、抗拉強(qiáng)度、屈強(qiáng)比顯著升高,當(dāng)冷卻速度達(dá)到20℃/s時(shí),抗拉強(qiáng)度最高可達(dá)到998MPa。(2)Mn-Ti型高強(qiáng)鋼控軋控冷工藝后控冷至320℃、280℃、240℃、170℃和100℃進(jìn)行卷取,觀察并研究了試驗(yàn)鋼的微觀組織對沖擊性能的影響,分析了不同卷取溫度下多種形態(tài)鐵素體、位錯(cuò)、M-A島對鋼材沖擊性能的控制機(jī)制。結(jié)果表明,隨著試驗(yàn)鋼卷取的溫度從320℃降到100℃,試驗(yàn)鋼微觀組織中位錯(cuò)結(jié)構(gòu)和細(xì)小M-A島的多邊形鐵素體最有利于沖擊吸收能量的增加;當(dāng)板條狀鐵素體和大尺寸M-A島出現(xiàn)時(shí),沖擊吸收能量下降;特別是較大長度的板條狀鐵素體形成時(shí),試驗(yàn)鋼的沖擊吸收能量下降至最小。(3)利用Gleeble-3800熱模擬在應(yīng)變速率為1s-1變形溫度在760℃、810℃、860℃、910℃、960℃和860℃下應(yīng)變速率分別為0.1s-1、1s-1、5s-1、10s-1進(jìn)行熱壓縮實(shí)驗(yàn),研究不同應(yīng)變速率和變形溫度熱變形參數(shù)對Mn-Ti型多相高強(qiáng)鋼變形后冷卻時(shí)相變過程和微觀組織特征的影響,以準(zhǔn)確地控制變形后的組織,優(yōu)化生產(chǎn)工藝及微觀組織。
[Abstract]:Iron and steel industry is the pillar industry of our national economy. At present, China's iron and steel industry is in the key period of resolving overcapacity. In addition, many domestic and foreign fields of steel also put forward a higher strength. In 21th century, the controlled rolling and cooling process is a new technology. Low carbon microalloyed high strength steel under controlled rolling and cooling control technology has not only achieved obvious results in improving the comprehensive properties of steel, but also has been widely used in iron and steel production. Moreover, controlled rolling and cooling control technology plays an important role in reducing energy consumption and developing green iron and steel materials. At present, it is the research hotspot of iron and steel scholars all over the world. In this paper, low carbon microalloyed Mn-Ti section steel under controlled rolling and controlled cooling process is studied under room temperature tensile deformation, low temperature impact and hot compression. The microstructure and mechanical properties of experimental steel under different experimental parameters were obtained. The evolution process of microstructure and the effect of microstructure on mechanical properties of experimental steel were analyzed. This paper provides a theoretical basis for the formulation of process parameters of controlled rolling and controlled cooling in the actual production process of iron and steel. The specific research contents are as follows: 1) the Mn-Ti type experimental steel is studied at 20 鈩，

本文編號：1450178