At different annealing temperatures, the saturation magnetostrictions and the correlation between the permeability μi and the temperature T (μi-T curves) of the Co66Fe4Mo2Si16B12 alloy were investigated using a sm...At different annealing temperatures, the saturation magnetostrictions and the correlation between the permeability μi and the temperature T (μi-T curves) of the Co66Fe4Mo2Si16B12 alloy were investigated using a small-angle magnetization tester and core tester. The experimental results showed that the μi-T curves had different shapes at different ranges of annealing temperature; the permeability μi of the alloy improved with the increase of the annealing temperatures below 460℃; when the alloy was annealed above 480℃, the poor magnetic properties were considered to be caused by larger saturation magnetostriction.展开更多
Amorphous ribbons of (Ni0.75Fe0.25)78-xNbxSi10B12(x=0,5) were prepared by a single roller melt-spinning technique in air atmosphere. The crystallization kinetics of the alloys were investigated by means of continuou...Amorphous ribbons of (Ni0.75Fe0.25)78-xNbxSi10B12(x=0,5) were prepared by a single roller melt-spinning technique in air atmosphere. The crystallization kinetics of the alloys were investigated by means of continuous heating,and the activation energies of the alloys were calculated using Kissinger plot method and Ozawa plot method on the basis of differential thermal analysis data. The crystallization products were analyzed by X-ray diffraction. After the (Ni0.75Fe0.25)78-xNbxSi10B12 amorphous alloy was annealed at the temperatures 715 and 745?K,a single phase of γ-(Fe,Ni) solid solution with grain sizes of about 10.3 and 18.5?nm,respectively,precipitates in the amorphous matrix. The crystallized phases are γ-(Fe,Ni) solid solution,Fe2Si,Ni2Si,and Fe3B after annealing at 765?K. The (Ni0.75Fe0.25)78-xNbxSi10B12 amorphous alloy was annealed at 720,750,and 800?K; and the crystallization phases,γ-(Fe,Ni) solid solution,(Fe,Ni) 23 B6,Ni 31 Si 12 and Nb2NiB 0.16 form simultaneously.展开更多
为提高Al-12Si合金的热变形抗力,并探索非晶Fe粉掺杂对Al-12Si合金热压缩行为的影响和掺杂非晶Fe粉热压缩中的晶化温度等,采用连续挤压技术制备了掺杂10wt%非晶Fe粉与不掺杂非晶Fe粉的Al-12Si合金试样,对试样进行了不同温度和应变速率...为提高Al-12Si合金的热变形抗力,并探索非晶Fe粉掺杂对Al-12Si合金热压缩行为的影响和掺杂非晶Fe粉热压缩中的晶化温度等,采用连续挤压技术制备了掺杂10wt%非晶Fe粉与不掺杂非晶Fe粉的Al-12Si合金试样,对试样进行了不同温度和应变速率下的热压缩试验,分析了试样在热压缩中的组织转变,以及采用双曲正弦关系构建了试样的热流变应力方程。结果表明:非晶Fe掺杂试样在450℃及以下的热压缩时,Fe维持非晶态,500℃时,则已发生晶化;掺杂10wt%非晶Fe粉使Al-12Si合金的热抗变形能力显著提高,其热压缩激活能Q=211. 29 k J/mol,比未掺杂非晶Fe粉的Al-12Si合金试样高40. 78 k J/mol,且热压缩过程中存在动态回复和动态再结晶;利用双曲正弦关系构建试样的热流变应力方程为■,线性回归系数高达0. 99,即可为非晶Fe粉掺杂试样的热加工提供一定的理论指导。展开更多
The Fe48Cr15Mo14Er2C15B6amorphous steel can hardly be used as an engineering material because of its ex- treme brittleness and very low iron content. By changing the composition of the nonmagnetic amorphous steel, and...The Fe48Cr15Mo14Er2C15B6amorphous steel can hardly be used as an engineering material because of its ex- treme brittleness and very low iron content. By changing the composition of the nonmagnetic amorphous steel, and using the relation between the reduced glass transition tempera- ture Trg and the glass forming ability, a new amorphous Fe56Mn5Cr7Mo12Er2C12B6 alloy with good glass forming abil- ity and high iron content was obtained. The diameter of the as-cast sample rod reached 8 mm. This new amorphous steel has lower manufacturing cost due to its high iron content, and thus it can have wider applications.展开更多
文摘At different annealing temperatures, the saturation magnetostrictions and the correlation between the permeability μi and the temperature T (μi-T curves) of the Co66Fe4Mo2Si16B12 alloy were investigated using a small-angle magnetization tester and core tester. The experimental results showed that the μi-T curves had different shapes at different ranges of annealing temperature; the permeability μi of the alloy improved with the increase of the annealing temperatures below 460℃; when the alloy was annealed above 480℃, the poor magnetic properties were considered to be caused by larger saturation magnetostriction.
文摘Amorphous ribbons of (Ni0.75Fe0.25)78-xNbxSi10B12(x=0,5) were prepared by a single roller melt-spinning technique in air atmosphere. The crystallization kinetics of the alloys were investigated by means of continuous heating,and the activation energies of the alloys were calculated using Kissinger plot method and Ozawa plot method on the basis of differential thermal analysis data. The crystallization products were analyzed by X-ray diffraction. After the (Ni0.75Fe0.25)78-xNbxSi10B12 amorphous alloy was annealed at the temperatures 715 and 745?K,a single phase of γ-(Fe,Ni) solid solution with grain sizes of about 10.3 and 18.5?nm,respectively,precipitates in the amorphous matrix. The crystallized phases are γ-(Fe,Ni) solid solution,Fe2Si,Ni2Si,and Fe3B after annealing at 765?K. The (Ni0.75Fe0.25)78-xNbxSi10B12 amorphous alloy was annealed at 720,750,and 800?K; and the crystallization phases,γ-(Fe,Ni) solid solution,(Fe,Ni) 23 B6,Ni 31 Si 12 and Nb2NiB 0.16 form simultaneously.
文摘为提高Al-12Si合金的热变形抗力,并探索非晶Fe粉掺杂对Al-12Si合金热压缩行为的影响和掺杂非晶Fe粉热压缩中的晶化温度等,采用连续挤压技术制备了掺杂10wt%非晶Fe粉与不掺杂非晶Fe粉的Al-12Si合金试样,对试样进行了不同温度和应变速率下的热压缩试验,分析了试样在热压缩中的组织转变,以及采用双曲正弦关系构建了试样的热流变应力方程。结果表明:非晶Fe掺杂试样在450℃及以下的热压缩时,Fe维持非晶态,500℃时,则已发生晶化;掺杂10wt%非晶Fe粉使Al-12Si合金的热抗变形能力显著提高,其热压缩激活能Q=211. 29 k J/mol,比未掺杂非晶Fe粉的Al-12Si合金试样高40. 78 k J/mol,且热压缩过程中存在动态回复和动态再结晶;利用双曲正弦关系构建试样的热流变应力方程为■,线性回归系数高达0. 99,即可为非晶Fe粉掺杂试样的热加工提供一定的理论指导。
基金This work was supported by the National Natural Science Foundation of China(Grans No.50371098 and 50321101)the Key Project of the Beiing Science and Technology Program(Contract No.H02040030320).
文摘The Fe48Cr15Mo14Er2C15B6amorphous steel can hardly be used as an engineering material because of its ex- treme brittleness and very low iron content. By changing the composition of the nonmagnetic amorphous steel, and using the relation between the reduced glass transition tempera- ture Trg and the glass forming ability, a new amorphous Fe56Mn5Cr7Mo12Er2C12B6 alloy with good glass forming abil- ity and high iron content was obtained. The diameter of the as-cast sample rod reached 8 mm. This new amorphous steel has lower manufacturing cost due to its high iron content, and thus it can have wider applications.