本文選題：稀土 + 低碳高鈮鋼�。� 參考：《內(nèi)蒙古科技大學(xué)》2015年碩士論文

【摘要】：隨著現(xiàn)代物理冶金技術(shù)的發(fā)展，低碳高鈮鋼成為目前鋼鐵材料中最廣泛應(yīng)用的鋼種。鈮、鈦在鋼材加熱過程中是否能較為充分的固溶對隨后的軋制過程中組織與性能的控制有重要影響。已有研究表明：低碳高鈮鋼中添加少量稀土，可以降低鈮、鈦的平衡固溶溫度，促進(jìn)鈮、鈦在鋼中的固溶，這對節(jié)省能源和提高鈮、鈦的利用率有非常重要的意義。但是對不同稀土添加量對鈮、鈦固溶以及奧氏體晶粒大小的影響還少有報(bào)道。本文以含微量稀土的低碳高鈮鋼為研究對象，對比含稀土與不含稀土的情況下，稀土對低碳高鈮鋼奧氏體化行為的影響，，以及對比不同稀土添加量對低碳高鈮鋼奧氏體化行為的影響，為正確制定低碳稀土高鈮鋼的加熱工藝提供實(shí)驗(yàn)依據(jù)。 本實(shí)驗(yàn)利用電感耦合等離子體原子發(fā)射光譜儀（ICP）測定了低碳高鈮鋼不同加熱條件下Nb、Ti的固溶量，采用光學(xué)顯微鏡獲取低碳高鈮鋼的原始奧氏體組織，并通過掃描電子顯微鏡和透射電子顯微鏡來觀察未固溶顆粒的大小及分布情況。以此來分析不同加熱工藝、不同稀土含量對低碳高鈮鋼奧氏體晶粒大小及分布、Nb和Ti的固溶、未固溶的第二相顆粒的影響。 實(shí)驗(yàn)結(jié)果表明：不含稀土的實(shí)驗(yàn)鋼隨著均熱溫度的升高、均熱時間的延長，鈮固溶百分量分別由13.9%升高到51.4%，鈦的固溶百分量由10.5%升高到41.0%；添加稀土的實(shí)驗(yàn)鋼在不同工藝下鈮、鈦固溶百分量變化不大，分別在70%和55%左右。在1250℃均熱1h時，添加稀土量為64ppm的實(shí)驗(yàn)鋼的平均晶粒尺寸比不添加稀土的實(shí)驗(yàn)鋼的平均晶粒尺寸小13μm；在1250℃均熱1h時，稀土含量為64ppm的實(shí)驗(yàn)鋼與未添加稀土的實(shí)驗(yàn)鋼相比，鈮固溶的百分含量提高了54.1%，鈦固溶的百分含量提高了44.9%。在1280℃均熱1h時，添加稀土的實(shí)驗(yàn)鋼的原始奧氏體晶粒大小與不添加稀土的基本相同，而鈮、鈦固溶的百分含量是添加稀土的比不添加稀土的分別高25.5%和13.7%。 不同稀土含量的兩種實(shí)驗(yàn)鋼在相同的溫度下鈮、鈦固溶的百分含量基本相同，并且在1250℃均熱40min后基本達(dá)到平衡。兩種含稀土的實(shí)驗(yàn)鋼在均熱溫度不超過1250℃時晶粒都較小且相差不大，當(dāng)加熱到1280℃和1300℃時，高的稀土添加量更能細(xì)化低碳高鈮鋼的原始奧氏體晶粒，稀土含量為40ppm的實(shí)驗(yàn)鋼的奧氏體平均晶粒尺寸要比稀土含量為6ppm的實(shí)驗(yàn)鋼分別小8.4μm和28.1μm。
[Abstract]:With the development of modern physical and metallurgical technology, low carbon and high niobium steel has become the most widely used steel in steel materials. It has an important effect on the control of microstructure and properties in the subsequent rolling process. The results show that the addition of a small amount of rare earth in low carbon and high niobium steel can be achieved. To reduce the equilibrium solution temperature of niobium and titanium and to promote the solid solution of niobium and titanium in steel, it is very important to save energy and improve the utilization of niobium and titanium. However, there are few reports on the effect of different addition of rare earth on niobium, titanium and austenite grain size. The influence of rare earth on austenitizing behavior of low carbon and high niobium steel and the effect of different rare earth addition on austenitizing behavior of low carbon and high niobium steel are compared in the case of rare earth and rare earth, and the experimental basis is provided for the correct formulation of the heating process of low carbon rare earth high niobium steel.
An inductively coupled plasma atomic emission spectrometer (ICP) was used to determine the solid solution of Nb and Ti in low carbon and high niobium steel under different heating conditions. The original austenite structure of low carbon and high niobium steel was obtained by optical microscope, and the size and distribution of undissolved particles were observed by scanning electron microscope and transmission electron microscopy. The effects of different heating processes on the grain size and distribution of austenite grain in low carbon high Nb steel, the solid solution of Nb and Ti and the second phase particles of unsolid solution in different heating processes are analyzed.
The experimental results show that with the increase of heat average temperature and the prolongation of heat average temperature, the 100 components of niobium solid solution increase from 13.9% to 51.4%, and the solid solution of titanium increases from 10.5% to 41%, and the 100 components of niobium and titanium with the addition of rare earth in different processes have little change, respectively, 70% and 55%, respectively, and 1250. The average grain size of experimental steel added with rare earth content of 64ppm is 13 m smaller than that of experimental steel that does not add rare earth, while the average grain size of the experimental steel with a rare earth content of 64ppm is 13 u m smaller than that of the experimental steel that does not add the rare earth. The content of the niobium solid solution increase by 54.1% and the content of the titanium solid solution increase by 44. compared with the experimental steel without the rare earth's rare earth content at the temperature of 1H. When 9%. is 1H at 1280 C, the original austenite grain size of the experimental steel adding rare earth is basically the same as that of the addition of rare earth, while the content of niobium and titanium in the solid solution is 25.5% and 13.7%. higher than that of the addition of rare earth.
The content of niobium and titanium in the two kinds of experimental steels with different rare-earth content is basically the same at the same temperature, and the equilibrium is basically reached after the heat of 40min at 1250. Two kinds of experimental steel with rare earth are smaller and have little difference when the temperature is not more than 1250 C. When heated to 1280 and 1300 degrees, the high rare earth addition can be more effective. The original austenite grain of low carbon and high niobium steel is refined. The average austenite grain size of the experimental steel with a rare earth content of 40ppm is 8.4 micron m and 28.1 M. smaller than that of the experimental steel with a rare earth content of 6ppm.

【學(xué)位授予單位】：內(nèi)蒙古科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TG142.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 宋文鐘;方琪;任慧平;金自力;常慧;孫偉;;稀土微合金鋼奧氏體晶界顯示技術(shù)[J];物理測試;2010年06期

2 陳希穎;中國稀土在鋼中的應(yīng)用[J];中國稀土學(xué)報(bào);1991年04期

3 王龍妹;稀土元素在新一代高強(qiáng)韌鋼中的作用和應(yīng)用前景[J];中國稀土學(xué)報(bào);2004年01期

4 劉勇華，葉文，林勤，陳寧;稀土對管線鋼中沉淀相和再結(jié)晶的影響[J];中國稀土學(xué)報(bào);1996年03期

5 王龍妹,杜挺,盧先利,樂可襄;微量稀土元素在鋼中的作用機(jī)理及應(yīng)用研究[J];稀土;2001年04期

6 林勤,宋波,張梅,高平祥,王躍華,唐天喜;新型高鑭混合稀土添加劑的開發(fā)與應(yīng)用[J];稀土;2001年04期

7 姜茂發(fā),王榮,李春龍;鋼中稀土與鈮、釩、鈦等微合金元素的相互作用[J];稀土;2003年05期

8 閆英，閆俊萍，李文學(xué)，王玉峰;稀土對T10碳素工具鋼中夾雜物的影響[J];稀土;1996年01期

9 田文洲;劉靜;袁澤喜;;冷變形后微合金鋼碳氮化物的析出與組織[J];武漢科技大學(xué)學(xué)報(bào)(自然科學(xué)版);2006年03期

10 郝飛飛;李達(dá);淡婷;任學(xué)軍;廖波;楊慶祥;;Effect of rare earth oxides on the morphology of carbides in hardfacing metal of high chromium cast iron[J];Journal of Rare Earths;2011年02期

本文編號：1783639