为了研究120 t BOF-LF-RH-160 mm×160 mm坯CC工艺生产的铝脱氧20钢(/%:0.13-0.23C,0.17~0.37Si,0.35~0.65Mn,≤0.035P,≤0.035S,0.020~0.050Al)中非金属夹杂物的控制技术,对LF精炼过程中脱氧剂加入时机进行调整,并对精炼过程中非...为了研究120 t BOF-LF-RH-160 mm×160 mm坯CC工艺生产的铝脱氧20钢(/%:0.13-0.23C,0.17~0.37Si,0.35~0.65Mn,≤0.035P,≤0.035S,0.020~0.050Al)中非金属夹杂物的控制技术,对LF精炼过程中脱氧剂加入时机进行调整,并对精炼过程中非金属夹杂物类型与夹杂物数量进行分析。结果表明,转炉出钢后采用铝块脱氧,LF精炼进站非金属夹杂物主要为Al_(2)O_(3),精炼结束前部分夹杂物由Al_(2)O_(3)转变为Al_(2)O_(3)·CaO,RH结束后非金属夹杂物密度3~4个/mm^(2),铸坯氧含量(7.48-8.18)×10^(-6);而转炉出钢后采用硅锰进行脱氧,精炼结束前采用铝线,精炼过程中夹杂物主要为MnO·SiO_(2),CaO含量小于5%,精炼结束非金属夹杂物控制为Al_(2)O_(3),RH真空处理后,非金属夹杂物密度小于1.5个/mm^(2),铸坯氧含量(4.94~5.53)×10^(-6)。因此,针对采用"BOF-LF-RH-CC"工艺流程生产的含铝钢,提出精炼结束前将非金属夹杂物控制为Al_(2)O_(3),同时运用RH真空高效去除夹杂物,以提高钢水的洁净度。展开更多
Ceramic fuel cells hold an important position for the sustainable energy future using renewable energy sources with high efficiency.The design and synthesis of active materials,interface engineering and having capabil...Ceramic fuel cells hold an important position for the sustainable energy future using renewable energy sources with high efficiency.The design and synthesis of active materials,interface engineering and having capability of low operating temperature is considered as an important factor to further increase the power output and stability of ceramic fuel cell devices.A novel methodology has vital importance to develop new functionalities of existing materials by introducing new different effects.The built-in electric field(BIEF) is one of the most recently used approaches to improve charge transfer and ionic conductivity of solid oxide materials.Herein,we demonstrate gradient doping strategy in CeO_(2)-δstructure to produce BIEF effect and to modulate the proton transport effectively at the surface layer rather than bulk structure.The inclusions of La and Sr metal ions at the surface and Co-metal ions into bulk-layer of CeO_(2)form the gradiently doped structure.The gradient doping into CeO_(2)highly improves the proton transport properties through the surface layer by modifying the energy levels.Moreover,unbalanced charge distribution due to gradient doping produces built-in electric-field to provide extra driving force for protons transport through surface layer.The acquired gradiently doped fluorite structure exhibits remarkable proton conductivity of>0.2 S/cm,as a result ceramic fuel cell shows power output of>1000 mW/cm2while operating at 500℃.This unique work highlights the critical role of gradiently doped electrolyte in electrochemical conversion energy devices and offers new understanding and practices for sustainable energy future.展开更多
文摘为了研究120 t BOF-LF-RH-160 mm×160 mm坯CC工艺生产的铝脱氧20钢(/%:0.13-0.23C,0.17~0.37Si,0.35~0.65Mn,≤0.035P,≤0.035S,0.020~0.050Al)中非金属夹杂物的控制技术,对LF精炼过程中脱氧剂加入时机进行调整,并对精炼过程中非金属夹杂物类型与夹杂物数量进行分析。结果表明,转炉出钢后采用铝块脱氧,LF精炼进站非金属夹杂物主要为Al_(2)O_(3),精炼结束前部分夹杂物由Al_(2)O_(3)转变为Al_(2)O_(3)·CaO,RH结束后非金属夹杂物密度3~4个/mm^(2),铸坯氧含量(7.48-8.18)×10^(-6);而转炉出钢后采用硅锰进行脱氧,精炼结束前采用铝线,精炼过程中夹杂物主要为MnO·SiO_(2),CaO含量小于5%,精炼结束非金属夹杂物控制为Al_(2)O_(3),RH真空处理后,非金属夹杂物密度小于1.5个/mm^(2),铸坯氧含量(4.94~5.53)×10^(-6)。因此,针对采用"BOF-LF-RH-CC"工艺流程生产的含铝钢,提出精炼结束前将非金属夹杂物控制为Al_(2)O_(3),同时运用RH真空高效去除夹杂物,以提高钢水的洁净度。
基金Project supported by the Fundamental Research Funds for the Central Universities (3203002105A2,4303002184)Jiangsu Provincial Program (JSSCRC2021491)。
文摘Ceramic fuel cells hold an important position for the sustainable energy future using renewable energy sources with high efficiency.The design and synthesis of active materials,interface engineering and having capability of low operating temperature is considered as an important factor to further increase the power output and stability of ceramic fuel cell devices.A novel methodology has vital importance to develop new functionalities of existing materials by introducing new different effects.The built-in electric field(BIEF) is one of the most recently used approaches to improve charge transfer and ionic conductivity of solid oxide materials.Herein,we demonstrate gradient doping strategy in CeO_(2)-δstructure to produce BIEF effect and to modulate the proton transport effectively at the surface layer rather than bulk structure.The inclusions of La and Sr metal ions at the surface and Co-metal ions into bulk-layer of CeO_(2)form the gradiently doped structure.The gradient doping into CeO_(2)highly improves the proton transport properties through the surface layer by modifying the energy levels.Moreover,unbalanced charge distribution due to gradient doping produces built-in electric-field to provide extra driving force for protons transport through surface layer.The acquired gradiently doped fluorite structure exhibits remarkable proton conductivity of>0.2 S/cm,as a result ceramic fuel cell shows power output of>1000 mW/cm2while operating at 500℃.This unique work highlights the critical role of gradiently doped electrolyte in electrochemical conversion energy devices and offers new understanding and practices for sustainable energy future.
