采用液态单辊急冷法,在大气下制备了几种非晶态新型代银钎料箔带,其材料的最佳成分数w(Cu)为68%～79%,w(Ni)为5%～14%,w(Sn)为4%～10%,w(P)为7%.在反复实验的基础上,确定了合理的钎料母合金熔炼工艺和单辊急冷法制备工艺,冷辊转速、喷...采用液态单辊急冷法,在大气下制备了几种非晶态新型代银钎料箔带,其材料的最佳成分数w(Cu)为68%～79%,w(Ni)为5%～14%,w(Sn)为4%～10%,w(P)为7%.在反复实验的基础上,确定了合理的钎料母合金熔炼工艺和单辊急冷法制备工艺,冷辊转速、喷嘴口尺寸、喷带的间隙和喷射压力是制备非晶态箔带的关键工艺参数.制得的几种非晶态新型代银钎料箔带成型性良好,对折180°不折断.并利用DTA,SEM及XRD等方法对Cu P非晶态钎料箔带的非晶形成能力及熔化特性进行了研究.结果表明,制备的Cu Ni Sn P非晶合金箔带熔点和润湿性与Ag基钎料接近.展开更多
采用粉末冶金温压成形技术研制了非晶Fe78Si9B13软磁粉芯,分别研究了粘结剂233耐高温有机硅树脂和JH1123两种粘结剂对该种软磁粉芯的微观形貌、密度、磁导率、损耗、品质因数的作用,结果表明：粘结剂对提高粉末的压坯密度有重要作用,粘...采用粉末冶金温压成形技术研制了非晶Fe78Si9B13软磁粉芯,分别研究了粘结剂233耐高温有机硅树脂和JH1123两种粘结剂对该种软磁粉芯的微观形貌、密度、磁导率、损耗、品质因数的作用,结果表明：粘结剂对提高粉末的压坯密度有重要作用,粘结剂的含量过高或过低都会降低磁粉芯的压坯密度。添加3.0%JH1123（质量分数,下同）粘结剂时获得的最高压坯密度是4.93 g/cm3。相比于硅树脂233粘结剂,同样含量下JH1123粘结剂对应的有效磁导率明显较高,添加3.0%JH1123粘结剂50 k Hz时的有效磁导率可达到最高值50.2（50 k Hz时）。50--200 k Hz下磁损耗均较小,品质因数在高频下可以保持在一个较高水平。展开更多
A novel process of electroplating amorphous Fe Cr Ni alloy in chloride aqueous solution with Fe(Ⅱ), Ni(Ⅱ) and Cr(Ⅲ) was reported. Couple plasma atomic emission spectrometry (ICP AES), X ray diffractometry(XRD), sca...A novel process of electroplating amorphous Fe Cr Ni alloy in chloride aqueous solution with Fe(Ⅱ), Ni(Ⅱ) and Cr(Ⅲ) was reported. Couple plasma atomic emission spectrometry (ICP AES), X ray diffractometry(XRD), scanning electronic microscopy(SEM), microhardness test and rapid heating cooling method were adopted to detect the properties of the amorphous Fe Ni Cr deposit, such as composition, crystalline structure, micrograph, hardness, and adherence between deposit and substrate. The effects of the operating parameters on the electrodeposit of the amorphous Fe Ni Cr alloy were discussed in detail. The results show that a 8.7?μm thick mirror like amorphous Fe Ni Cr alloy deposit, with Vicker’s hardness of 530 and composition of 45%～55% Fe, 33%～37% Ni, 9%～23% Cr was obtained by electroplating for 20?min at room temperature(10～30?℃), cathode current 10～16?A/dm 2, pH=1.0～3.0. The XRD patterns show that there only appears a broad hump around 2 θ of 41?°～47?°for the amorphous Fe Ni Cr alloy deposit, while the SEM micrographs show that the deposit contains only a few fine cracks but no pinholes.展开更多
1.IntroductionMechanical alloying is one of the effec-tive methods to prepare amorphous alloys[1].This method was first used by Koch etal.to prepare the Ni;Nb;amorphous alloy[2].Since then many other amorphousbinary ... 1.IntroductionMechanical alloying is one of the effec-tive methods to prepare amorphous alloys[1].This method was first used by Koch etal.to prepare the Ni;Nb;amorphous alloy[2].Since then many other amorphousbinary alloys have been prepared by the展开更多
The development of cost-effective and highperformance electrocatalysts has been increasingly studied to mitigate upcoming energy and environmental challenges.Amorphization and heterointerface engineering have played s...The development of cost-effective and highperformance electrocatalysts has been increasingly studied to mitigate upcoming energy and environmental challenges.Amorphization and heterointerface engineering have played significant roles in the rational design of electrocatalysts and modulation of their electrocatalytic activities.However,the synergistic effect between amorphization and heterointerfaces has been scarcely reported.As a proof-of-concept attempt,we develop amorphous FeMo(a-FeMo)electrocatalysts with an abundance of heterointerfaces that are composed of amorphous components and evaluate their electrocatalytic performances toward the nitrogen reduction reaction and oxygen evolution reaction(OER).Benefitting from the synergistic effect between the amorphous nature of the a-FeMo electrocatalysts,which offer a high density of active sites,and significant electron redistribution at the heterointerfaces,the electrocatalysts exhibit a high Faradaic efficiency of 29.15%,an elevated yield rate of 71.78μg_(NH_(3)) mg_(cat.)^(-1) h^(-1) with long-term stability at a potential of-0.1V vs.reversible hydrogen electrode and excellent electrocatalytic activity toward the OER.This study provides a promising and effective method for the rational design of low-cost heterogeneous catalysts with desirable efficiency,selectivity,and stability.展开更多
文摘采用液态单辊急冷法,在大气下制备了几种非晶态新型代银钎料箔带,其材料的最佳成分数w(Cu)为68%～79%,w(Ni)为5%～14%,w(Sn)为4%～10%,w(P)为7%.在反复实验的基础上,确定了合理的钎料母合金熔炼工艺和单辊急冷法制备工艺,冷辊转速、喷嘴口尺寸、喷带的间隙和喷射压力是制备非晶态箔带的关键工艺参数.制得的几种非晶态新型代银钎料箔带成型性良好,对折180°不折断.并利用DTA,SEM及XRD等方法对Cu P非晶态钎料箔带的非晶形成能力及熔化特性进行了研究.结果表明,制备的Cu Ni Sn P非晶合金箔带熔点和润湿性与Ag基钎料接近.
文摘采用粉末冶金温压成形技术研制了非晶Fe78Si9B13软磁粉芯,分别研究了粘结剂233耐高温有机硅树脂和JH1123两种粘结剂对该种软磁粉芯的微观形貌、密度、磁导率、损耗、品质因数的作用,结果表明：粘结剂对提高粉末的压坯密度有重要作用,粘结剂的含量过高或过低都会降低磁粉芯的压坯密度。添加3.0%JH1123（质量分数,下同）粘结剂时获得的最高压坯密度是4.93 g/cm3。相比于硅树脂233粘结剂,同样含量下JH1123粘结剂对应的有效磁导率明显较高,添加3.0%JH1123粘结剂50 k Hz时的有效磁导率可达到最高值50.2（50 k Hz时）。50--200 k Hz下磁损耗均较小,品质因数在高频下可以保持在一个较高水平。
文摘A novel process of electroplating amorphous Fe Cr Ni alloy in chloride aqueous solution with Fe(Ⅱ), Ni(Ⅱ) and Cr(Ⅲ) was reported. Couple plasma atomic emission spectrometry (ICP AES), X ray diffractometry(XRD), scanning electronic microscopy(SEM), microhardness test and rapid heating cooling method were adopted to detect the properties of the amorphous Fe Ni Cr deposit, such as composition, crystalline structure, micrograph, hardness, and adherence between deposit and substrate. The effects of the operating parameters on the electrodeposit of the amorphous Fe Ni Cr alloy were discussed in detail. The results show that a 8.7?μm thick mirror like amorphous Fe Ni Cr alloy deposit, with Vicker’s hardness of 530 and composition of 45%～55% Fe, 33%～37% Ni, 9%～23% Cr was obtained by electroplating for 20?min at room temperature(10～30?℃), cathode current 10～16?A/dm 2, pH=1.0～3.0. The XRD patterns show that there only appears a broad hump around 2 θ of 41?°～47?°for the amorphous Fe Ni Cr alloy deposit, while the SEM micrographs show that the deposit contains only a few fine cracks but no pinholes.
文摘 1.IntroductionMechanical alloying is one of the effec-tive methods to prepare amorphous alloys[1].This method was first used by Koch etal.to prepare the Ni;Nb;amorphous alloy[2].Since then many other amorphousbinary alloys have been prepared by the
基金supported by the National Natural Science Foundation of China(U2032149)Shenzhen Science and Technology Project(JCYJ20180507182246321)+3 种基金Hunan Provincial Natural Science Foundation of China(2020JJ2001)Hefei National Laboratory for Physical Sciences at the Microscale(KF2020108)the Fundamental Research Funds for the Central UniversitiesChina Postdoctoral Science Foundation(2019M663058 and 2019M652749).
文摘The development of cost-effective and highperformance electrocatalysts has been increasingly studied to mitigate upcoming energy and environmental challenges.Amorphization and heterointerface engineering have played significant roles in the rational design of electrocatalysts and modulation of their electrocatalytic activities.However,the synergistic effect between amorphization and heterointerfaces has been scarcely reported.As a proof-of-concept attempt,we develop amorphous FeMo(a-FeMo)electrocatalysts with an abundance of heterointerfaces that are composed of amorphous components and evaluate their electrocatalytic performances toward the nitrogen reduction reaction and oxygen evolution reaction(OER).Benefitting from the synergistic effect between the amorphous nature of the a-FeMo electrocatalysts,which offer a high density of active sites,and significant electron redistribution at the heterointerfaces,the electrocatalysts exhibit a high Faradaic efficiency of 29.15%,an elevated yield rate of 71.78μg_(NH_(3)) mg_(cat.)^(-1) h^(-1) with long-term stability at a potential of-0.1V vs.reversible hydrogen electrode and excellent electrocatalytic activity toward the OER.This study provides a promising and effective method for the rational design of low-cost heterogeneous catalysts with desirable efficiency,selectivity,and stability.
