本文通过表面纳米化处理( SMAT)在P92钢表层中形成纳米组织结构,研究了回火温度对表层纳米组织演化行为和析出行为的影响。结果表明:淬火态和回火态P92钢组织经过SMAT处理后沿深度方向依次是纳米层、剧烈变形层、最终过渡到正常组织。随后分别研究了淬火和回火态SMAT试样经不同温度回火后微观组织的再结晶及长大行为。经SMAT处理的铁素体纳米晶粒在550℃时仍能保持较好的纳米结构,甚至高达650℃时表层晶粒仍为纳米晶,当温度超过760℃时表层组织发生显著的再结晶和晶粒长大现象。纳米晶界能抑制淬火态P92钢在较低温度回火时M23 C6碳化物的析出。纳米组织提高了高温回火过程中合金元素在铁素体中的扩散速率,加速了M23 C6碳化物的长大过程。不同温度回火过程中SMAT纳米层中析出行为的变化将在本文中详细描述。
High temperature oxidation resistance of P92 steels can be further improved by the nanocrystalline microstructure of a surface layer induced by surface mechanical attrition treatment. Thermal stability of nanocrystalline microstructure was also studied. The results indicate that there are nanocrystalline layer, severely deformed surface layer and matrix along depth in the surface layer of the quenching and tempering state SMAT specimens. The microstructure is still nanocrystalline at 550 ℃ and 650 ℃. Precipitation behaviors of carbides could be inhibited in the nanocrystalline layer at the lower tempering temperature, however, the nanocrystalline accelerate the coarsening of carbides at 760 ℃. The recrystallization and abnormal growth of ferritic grains are attributed to the change of strain along depth in the surface layer at 760℃.
参考文献
[1] | Fujimitsu MASUYAMA .History of Power Plants and Progress in Heat Resistant Steels[J].ISIJ International,2001(6):612-625. |
[2] | Xia, Z.X.;Zhang, C.;Fan, N.Q.;Zhao, Y.F.;Xue, F.;Liu, S.J..Improve creep properties of reduced activation steels by controlling precipitation behaviors[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2012:91-96. |
[3] | 赵彦芬,张路,王正品,刘江南.高温过热器T91、T22管爆管分析[J].热力发电,2004(11):61-64. |
[4] | 钟万里,盘荣旋.超临界锅炉高温过热器T91钢管爆管分析[J].理化检验-物理分册,2009(07):440-442,445. |
[5] | 李铁藩.金属高温氧化和热腐蚀[M].北京:化学工业出版社,2003 |
[6] | K. Lu;J. Lu .Nanostructured surface layer on metallic materials induced by surface mechanical attrition treatment[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2004(0):38-45. |
[7] | 李辛庚,王学刚,何家文.喷丸与电泳沉积稀土薄膜复合处理提高T91钢抗水蒸气氧化性能的研究[J].中国腐蚀与防护学报,2002(02):101-104. |
[8] | 王群,丁彰雄,詹旺滨.三种用于锅炉管道涂层材料抗高温氧化性能的研究[J].湖南冶金,2003(01):12-15. |
[9] | 耿波,刘江南,赵颜芬,王正品,石崇哲.T91钢高温水蒸汽氧化层形成机理研究[J].铸造技术,2004(12):914-918. |
[10] | 王正品,张路,刘江南,赵彦芬,耿波,王东辉.电站用T22及与T91管高温蒸汽氧化的失效分析[J].铸造技术,2004(07):523-525. |
[11] | Xia, Z.X.;Zhang, C.;Yang, Z.G. .Control of precipitation behavior in reduced activation steels by intermediate heat treatment[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2011(22):6764-6768. |
[12] | Xia, Z.X.;Zhang, C.;Lan, H.;Yang, Z.G. .TaC precipitation behaviors in reduced activation martensitic steels[J].Journal of Materials Science,2011(9):3151-3156. |
[13] | L.M. Wang;Z.B. Wang;K. Lu .Grain size effects on the austenitization process in a nanostructured ferritic steel[J].Acta materialia,2011(9):3710-3719. |
[14] | 马荣,燕青芝,杨亚峰,杨英,葛昌纯.9Cr低活化马氏体钢冷变形及退火再结晶[J].金属热处理,2010(08):52-56. |
[15] | 肖翔,刘国权,胡本芙,胡加学,康人木,郑晓.冷变形对12Cr铁素体/马氏体钢回复与再结晶过程的影响[J].材料工程,2011(02):73-78. |
[16] | KIRCHHEIM R .Reducing grain boundary,dislocation line and vacancy formation energies by solute segregation I.Theoretical background.Experimental evidence and consequences[J].Acta Materialia,2007,55:5129-5138. |
[17] | Reiner Kirchheim .Reducing grain boundary, dislocation line and vacancy formation energies by solute segregation II. Experimental evidence and consequences[J].Acta materialia,2007(15):5139-5148. |
[18] | CHEN Y;HERZ A;KIRCHHEIM R .Grain boundary segregation of carbon and formation of nanocrystalline iron and carbon alloys by ball milling[J].Materials Science Forum,2011,667:265-270. |
[19] | L. Lu;L. B. Wang;B. Z. Ding;K. Lu .Comparison of the thermal stability between electro-deposited and cold-rolled nanocrystalline copper samples[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2000(1):125-129. |
[20] | 潘金生;仝健民;田民波.材料科学基础[M].北京:清华大学出版社,1998 |
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