The high-carbon ferrochrome is an essential raw material for producing stainless steel,and the demand of it increases with the increase of stainless steel.So increasing Cr recovery rate from chromite is essential for ...The high-carbon ferrochrome is an essential raw material for producing stainless steel,and the demand of it increases with the increase of stainless steel.So increasing Cr recovery rate from chromite is essential for lower costs and higher economic benefits in high-carbon ferrochrome production process.This study calculated the activity of CrO_(x)in slag and investigated the distribution behavior of Cr between slag and alloy.Theω(MgO)/ω(Al_(2)O_(3))was 1.0,and the w(CaO)/w(SiO_(2))was from 0.2 to 0.6 in this study.The calculation and experimental results showed that the main phases of the slag were chrome-containing spinel,magnesium-aluminum spinel,olivine and melilite.The content of spinel in slag decreased with the increasing w(CaO)/w(SiO_(2)),and the w(CrO_(x))in spinel also reduced,but the content of melilite increased.The distribution ratio of Cr between slag and alloy decreased with the increase of slag basicity at 1600℃,meansning that increasing the w(CaO)/w(SiO_(2))of slag can improve the recovery of Cr in chromite smelting process.展开更多
目的探究Cr/CrN/Cr/CrAlN多层膜的最佳调制比。方法利用电弧离子镀技术,在TC4钛合金上制备了不同调制比的Cr/CrN/Cr/CrAlN多层膜。利用扫描电子显微镜观察膜层表面和截面形貌;用Image-Pro分析软件对表面的大颗粒进行定量分析;利用X射线...目的探究Cr/CrN/Cr/CrAlN多层膜的最佳调制比。方法利用电弧离子镀技术,在TC4钛合金上制备了不同调制比的Cr/CrN/Cr/CrAlN多层膜。利用扫描电子显微镜观察膜层表面和截面形貌;用Image-Pro分析软件对表面的大颗粒进行定量分析;利用X射线衍射法表征膜层的晶体结构;采用维氏硬度计测量膜层的显微硬度;采用划痕试验仪测量膜层与基体之间的结合力(临界载荷);通过基片弯曲法测量并计算得到膜层的残余应力;利用根据ASTM G76-05标准特制的AS600-喷砂试验机进行了抗冲蚀性能测试;采用三维表面轮廓仪测量冲蚀坑深度。结果膜层表面质量和生长取向与L_(Cr/CrN):L_(Cr/CrAlN)调制比密切相关,随着Cr/CrN比例的增加,膜层表面质量越来越好,择优取向由(111)晶面转为(200)晶面。多层膜的硬度随Cr/CrN比例的增加,呈下降趋势,结合力、残余应力和韧性则随之呈先升后降的趋势,并在L_(Cr/CrN)∶LCr/Cr Al N为1∶2时,达到最佳。多层膜的抗砂粒冲蚀性能变化与力学性能变化一致,在L_(Cr/CrN)∶L_(Cr/CrAlN)为1∶2时达到最佳,其抗冲蚀能力是TC4基材的3倍以上,多层膜呈典型的脆性断裂失效形式。结论在调制比L_(Cr/CrN)∶L_(Cr/CrAlN)=1∶2时,膜层获得最佳的抗冲蚀性能。展开更多
采用1.0、1.2、1.4和1.6的轧制异速比对高温退火Cr Co Ni中熵合金进行室温和深冷异步轧制,并对轧后的材料在873、973和1073 K退火处理0.5 h。采用透射电子显微镜对轧制态样品进行微观表征,发现轧制态合金晶粒尺寸随着异速比增加而减小,...采用1.0、1.2、1.4和1.6的轧制异速比对高温退火Cr Co Ni中熵合金进行室温和深冷异步轧制,并对轧后的材料在873、973和1073 K退火处理0.5 h。采用透射电子显微镜对轧制态样品进行微观表征,发现轧制态合金晶粒尺寸随着异速比增加而减小,且存在明显的孪晶。室温异步轧制实验显示,轧制后轧制态和退火态合金的抗拉强度均随着轧制异速比的增加而增加。深冷轧制制备的材料具有比室温轧制更高的强度,但深冷轧制过程异速比对材料强度影响不明显。在深冷异步轧制过程中,由于内应力和轧制缺陷的累积使得异速比强化有一定的饱和度。采用场发射扫描电子显微镜对拉伸试样的断口形貌进行表征,发现室温异步轧制后合金具有明显的韧窝,而深冷异步轧制韧窝相对较浅,为剪切断裂。展开更多
基金Project(2023XQLH055)supported by Central South University Graduate Research Innovation Project(University-Enterprise Joint Project),China。
文摘The high-carbon ferrochrome is an essential raw material for producing stainless steel,and the demand of it increases with the increase of stainless steel.So increasing Cr recovery rate from chromite is essential for lower costs and higher economic benefits in high-carbon ferrochrome production process.This study calculated the activity of CrO_(x)in slag and investigated the distribution behavior of Cr between slag and alloy.Theω(MgO)/ω(Al_(2)O_(3))was 1.0,and the w(CaO)/w(SiO_(2))was from 0.2 to 0.6 in this study.The calculation and experimental results showed that the main phases of the slag were chrome-containing spinel,magnesium-aluminum spinel,olivine and melilite.The content of spinel in slag decreased with the increasing w(CaO)/w(SiO_(2)),and the w(CrO_(x))in spinel also reduced,but the content of melilite increased.The distribution ratio of Cr between slag and alloy decreased with the increase of slag basicity at 1600℃,meansning that increasing the w(CaO)/w(SiO_(2))of slag can improve the recovery of Cr in chromite smelting process.
文摘目的探究Cr/CrN/Cr/CrAlN多层膜的最佳调制比。方法利用电弧离子镀技术,在TC4钛合金上制备了不同调制比的Cr/CrN/Cr/CrAlN多层膜。利用扫描电子显微镜观察膜层表面和截面形貌;用Image-Pro分析软件对表面的大颗粒进行定量分析;利用X射线衍射法表征膜层的晶体结构;采用维氏硬度计测量膜层的显微硬度;采用划痕试验仪测量膜层与基体之间的结合力(临界载荷);通过基片弯曲法测量并计算得到膜层的残余应力;利用根据ASTM G76-05标准特制的AS600-喷砂试验机进行了抗冲蚀性能测试;采用三维表面轮廓仪测量冲蚀坑深度。结果膜层表面质量和生长取向与L_(Cr/CrN):L_(Cr/CrAlN)调制比密切相关,随着Cr/CrN比例的增加,膜层表面质量越来越好,择优取向由(111)晶面转为(200)晶面。多层膜的硬度随Cr/CrN比例的增加,呈下降趋势,结合力、残余应力和韧性则随之呈先升后降的趋势,并在L_(Cr/CrN)∶LCr/Cr Al N为1∶2时,达到最佳。多层膜的抗砂粒冲蚀性能变化与力学性能变化一致,在L_(Cr/CrN)∶L_(Cr/CrAlN)为1∶2时达到最佳,其抗冲蚀能力是TC4基材的3倍以上,多层膜呈典型的脆性断裂失效形式。结论在调制比L_(Cr/CrN)∶L_(Cr/CrAlN)=1∶2时,膜层获得最佳的抗冲蚀性能。
文摘采用1.0、1.2、1.4和1.6的轧制异速比对高温退火Cr Co Ni中熵合金进行室温和深冷异步轧制,并对轧后的材料在873、973和1073 K退火处理0.5 h。采用透射电子显微镜对轧制态样品进行微观表征,发现轧制态合金晶粒尺寸随着异速比增加而减小,且存在明显的孪晶。室温异步轧制实验显示,轧制后轧制态和退火态合金的抗拉强度均随着轧制异速比的增加而增加。深冷轧制制备的材料具有比室温轧制更高的强度,但深冷轧制过程异速比对材料强度影响不明显。在深冷异步轧制过程中,由于内应力和轧制缺陷的累积使得异速比强化有一定的饱和度。采用场发射扫描电子显微镜对拉伸试样的断口形貌进行表征,发现室温异步轧制后合金具有明显的韧窝,而深冷异步轧制韧窝相对较浅,为剪切断裂。
