制备工艺对Al-5Ti-0.25C-2RE组织及细化效果的影响

采用两种不同的RE添加工艺制备了Al-5Ti-0.25C-2RE细化剂,并利用光学显微镜(OM)和X射线衍射仪(XRD)等研究了Al-5Ti-0.25C-2RE显微组织及其对纯铝的细化效果.结果表明,两种制备工艺所得Al-5Ti-0.25C-2RE细化剂的组织均由α-Al基体、长条状TiAl3相、TiC颗粒、包裹状和不规则块状Ti2Al20Ce相组成.采用先加稀土工艺制备的Al-5Ti-0.25C-2RE细化剂由于稀土元素促进了TiC粒子形成并充分改善了TiAl3相的尺寸,在0.5%的添加量时比后加RE制备的细化剂获得了更加优异的细化效果.     

RE对Al-5Ti-0.25C细化性能的影响

采用光学显微镜(OM)和X射线衍射仪(XRD)等分析手段,研究了RE对Al-5Ti-0.25C细化性能的影响,并对其细化机制进行了分析探讨。结果表明,加入质量分数为0.5%的Al-5Ti-0.25C中间合金能将3003铝合金晶粒尺寸细化至403μm,而Al-5Ti-0.25C-2RE中间合金中由于RE元素的加入,w(Al-5Ti-0.25C-2RE)=0.5%的中间合金可将3003铝合金晶粒尺寸细化至172μm。RE元素能够促进TiC粒子和TiAl3相生成,并促进TiC粒子在基体中均匀弥散分布,改变TiAl3形貌,还能与熔体发生反应生成Ti2Al20Ce相。     

新型Al-Ti-B-RE中间合金的合成及其细化性能的研究（英文）

为优化铝中间合金细化剂的组织,提升细化性能,采用熔配法工艺合成新型Al-Ti-B-RE中间合金晶粒细化剂,合成反应基于热力学和动力学分析是可能的、存在的、自发向右进行,在适当的工艺条件下,在基体中可生成均匀弥散分布的第二相Al_3Ti、TiB_2、Ti_2Al_(20)RE等粒子。采用X射线衍射(XRD)、扫描电镜(SEM)、光学显微镜(OM)和力学拉伸试验等分析方法对所合成材料的微观组织、细化效果及力学性能进行了表征。细化试验表明:自制的Al-5Ti-1B-1RE中间合金细化工业纯铝时,其平均晶粒尺寸小于150μm到达细晶粒度级别。拉伸试验表明:工业纯铝中加入0.2%自制的Al-5Ti-1B-1RE中间合金晶粒细化剂后有更优的机械性能,与未细化工业纯铝相比,抗拉强度提高了28.39 MPa,延伸率增加了29.97%,其性能明显优于某国产的Al-5Ti-1B丝中间合金细化剂。     

采用Ce2O3制备的Al-Ti-C-Ce合金的组织及细化性能

采用氟盐法按w(Ti)∶w(C)=15∶1比例,加入1%的Ce制备了Al-4.5Ti-0.3C-1Ce中间合金,应用OM、SEM、EDAX及EPMA等手段分析了中间合金的成分、组织及细化特性。结果表明,由于Ce的加入,改善了TiAl3、TiC的形态和分布,细化了TiC粒子,使生成的TiC与TiAl3相分布均匀,稀土Ce和TiAl3反应生成Ti2Al20Ce相,主要富集在白色块状的TiAl3相上;Al-4.5Ti-0.3C-1Ce合金细化剂对纯铝的细化效果显著,当Ti添加量为0.015%时,纯铝的晶粒尺寸达70μm,细化效果最优。     

高品质Al-5Ti-1B合金线的组织与晶粒细化性能

采用等离子体发射光谱仪、光学显微镜、X射线衍射仪和扫描电镜,研究了高品质Al-5Ti-1B合金线的化学成分、显微组织和晶粒细化性能。结果表明,高品质Al-5Ti-1B合金线的Ti、B合金元素含量稳定,Fe、Si、V、K杂质元素含量低。合金线的组织均匀细小,无氧化夹杂物,TiAl3相平均尺寸为16.7μm,TiB2粒子平均尺寸为0.73μm。添加质量分数为0.2%的高品质Al-5Ti-1B合金线可使纯铝铸态晶粒细化到75.7μm,晶粒细化响应时间块,抗衰退能力强,适应铝熔体温度范围宽。研究结果可为细化剂生产企业和铝加工企业在生产、选用高品质Al-5Ti-1B合金线时提供参考。     

Al-Ti-C-RE中间合金的制备及细化性能研究

以工业纯铝、Ti粉、石墨粉、富铈稀土为主要原料,制备了Al-5Ti-0.25C-2RE中间合金,并对纯铝进行了细化试验.通过光学显微镜、X射线衍射、扫描电镜以及能谱分析等方法,研究了该中间合金的微观组织和细化性能.结果表明:Al-5Ti-0.25C-2RE细化剂主要由α-Al基体、TiAl3、TiC、Al20Ti2Ce等相组成;稀土元素的加入促进了TiC的形成;细化剂最佳添加量为0.5wt％,保温120 min,此时细化剂都具有良好的细化效果.     

动态合成对制备新型Al-Ti-B-RE细化剂第二相粒子的影响北大核心CSCD

为进一步优化铝中间合金细化剂的组织,提升细化性能,采用动态合成工艺制备新型Al-5Ti-1B-1RE中间合金晶粒细化剂,并与常规制备工艺进行对比,对所合成的中间合金的微观组织、细化工业纯铝的效果及力学性能进行了分析。试验结果表明:动态合成工艺制备的新型Al-5Ti-1B-1RE中间合金细化剂中的第二相粒子在Al基体中分布更具有细小均匀性;细化工业纯铝时,细化效果更好,细化后工业纯铝的极限拉伸强度和伸长率得以提高。     

电磁搅拌对Al-3Ti-0.2C-5Sr显微组织及细化性能的影响

研究了电磁搅拌对Al-3Ti-0.2C-5Sr细化剂显微组织的影响,并将电磁搅拌后的Al-3Ti-0.2C-5Sr添加到Al-7Si合金中进行细化试验。结果表明:随着搅拌时间的延长,Ti Al3相逐渐消失,大块状或板条状Al-Ti-Sr相转化为小块状,块状Al4Sr相转化为细针状,Ti C颗粒分布更加均匀;随着搅拌频率的提高,块状Al-Ti-Sr相尺寸减小;电磁搅拌后的Al-3Ti-0.2C-5Sr可将Al-7Si合金晶粒尺寸由1 195μm细化至210μm,保温60 min后未出现细化衰退现象。     

Synthesis and Refinement Performance of the Novel Al-Ti-B-RE Master Alloy Grain Refiner

为优化铝中间合金细化剂的组织,提升细化性能,采用熔配法工艺合成新型Al-Ti-B-RE中间合金晶粒细化剂,合成反应基于热力学和动力学分析是可能的、存在的、自发向右进行,在适当的工艺条件下,在基体中可生成均匀弥散分布的第二相A13Ti、TiB2、Ti2A120RE等粒子。采用X射线衍射（XRD）、扫描电镜（SEM）、光学显微镜（OM）和力学拉伸试验等分析方法对所合成材料的微观组织、细化效果及力学性能进行了表征。细化试验表明：自制的Al-5Ti-1B-1RE中间合金细化工业纯铝时,其平均晶粒尺寸小于150 μm到达细晶粒度级别。拉伸试验表明:工业纯铝中加入0.2%自制的Al-5Ti-1B-1RE中间合金晶粒细化剂后有更优的机械性能,与未细化工业纯铝相比,抗拉强度提高了28.39 MPa,延伸率增加了29.97%,其性能明显优于某国产的Al-5Ti-1B丝中间合金细化剂     

电磁搅拌连续铸挤Al-5Ti-1B合金的组织与晶粒细化效果

采用电磁搅拌连续铸挤工艺成形Al-5Ti-1B合金线,利用等离子体发射光谱仪、光学显微镜、X射线衍射仪和扫描电镜研究了Al-5Ti-1B合金线的组织与晶粒细化效果,并与Al-5Ti-1B合金锭进行了比较。结果表明,通过中间包电磁搅拌和连续铸挤成形过程中半固态剪切搅拌和剧塑性变形作用,可细化TiAl3相尺寸,改善TiB2粒子的分布状态,TiAl3相为细小块状,TiB2粒子弥散分布于α-Al基体中。Al-5Ti-1B合金线的晶粒细化能力增强,纯铝中添加0.2%的Al-5Ti-1B合金线静止5min,晶粒平均尺寸可细化至223μm,静止180min,晶粒平均尺寸为316μm。     

Al-Ti-B-RE细化剂对Al-7．0Si-0．55Mg合金显微组织和力学性能的影响

研究添加Al-5Ti-lB-RE细化剂对Al-7．0Si-0．55Mg（A357）合金的显微组织和力学性能的影响。先利用真空熔炼技术制各Al-7．0Si-0．55Mg合金,然后在Al-7．0Si-0．55Mg合金中加入不同成分的Al-5Ti-1B-RE中间合金。通过X射线衍射仪（XRD）、金相显微镜（OM）和扫描电子显微镜（SEM）对显微组织和拉伸试样的断口形貌进行观察。在室温下对合金的力学性能进行测试。观察Al-5Ti-1B-RE细化剂的形态以及内部结构,可以发现以TiB,为异质形核核心的TiAl3／Ti2Al20RE的壳层结构相。在Al-7．0Si-0．55Mg合金中加入Al-5Ti-1B-3．0RE细化剂后,抗拉强度会有明显提升,直到0．2％添加量时,抗拉强度会达到峰值。     

Effect of a grain refiner cum modifier on mechanical properties of Al-7Si and Al-11Si alloys

This study evaluates the influence of grain refiners/modifiers on the mechanical properties of the Al-7Si and Al-11Si alloys with an experiment of quantitative and qualitative correlations with the microstructure. Modification of Al-Si alloys with strontium additions and grain refinement with Al-Ti, Al-B and Al-T-B master alloy additions are demonstrated to be efficient on Al-Si alloys. A single master alloy with combined additions of Sr and Ti and/or B was prepared and the microstructure and mechanical properties were studied. The results show that boron rich (Al-3B-Sr and Al-1Ti-3B-Sr) master alloys are more efficient than Ti rich (Al-3Ti-Sr and Al-5Ti-1B-Sr) master alloys considering their combined grain refinement and modification effect on Al-7Si and Al-11Si alloys. However, the presence of Sr does not influence the grain refinement. Similarly, presence of grain refiner does not influence the modification of eutectic Si.     

Grain Refining Efficiency of SHS Al-Ti-B-C Master Alloy for Pure Aluminum and Its Effect on Mechanical Properties

A new Al-5Ti-0.75B-0.2C master alloy was successfully prepared by self-propagating high-temperature(SHS)reaction from an Al-Ti-B_4C system with molten Al.Microstructure and phase characterization of the prepared Al-5Ti-0.75B-0.2C master alloy show that the nearly spherical TiC particles,hexagonal or rectangular TiB_2 particles,and blocklike TiAl_3 particles distribute uniformly in the aluminum matrix.Grain refining test on commercial pure aluminum indicates that Al-5Ti-0.75B-0.2C master alloy exhibits a better grain refining performance than Al-5Ti-lB master alloy.By addition of 0.2 wt%Al-5Ti-0.75B-0.2C master alloy,the average grain size of a-Al can be effectively refined to160 ± 5 μm from about 3000 μm,and the tensile strength and elongation are increased by about 20%and 14.1%due to the grain refinement.     

比压和双细化剂对挤压铸造Al-Zn-Mg-Cu合金组织的影响

采用挤压铸造工艺制备了高速机车用Al-Zn-Mg-Cu合金传动空心轴,研究了比压和Al-5Ti-1B+Al-10RE双细化剂对挤压铸造Al-Zn-Mg-Cu合金传动空心轴微观组织的影响。结果表明,随着比压的不断增大,挤压铸造Al-Zn-Mg-Cu合金空心轴试样中初生α-Al晶粒的形状不断变得圆整,晶粒尺寸不断变小;当比压达到160MPa时,初生α-Al晶粒中粗大的树枝晶基本消失,试样组织为非枝晶组织,试样的平均晶粒直径为25μm,平均等效圆度为0.73;随着双细化剂中Al-5Ti-1B加入量的减少、Al-10RE加入量的增加,试样的平均晶粒直径显著减小,而试样的平均等效圆度变化不大,基本上在0.65～0.75之间;当添加1%的Al-5Ti-1B+3%的Al-10RE时,试样的平均晶粒直径为21μm,平均等效圆度为0.70。     

The grain refinement of 6063 aluminum using Al-5Ti-1B and Al-3Ti-0.15C grain refiners

The Al-Ti-B grain refiners containing boride nucleant particles are used to promote a uniform microstructure throughout aluminum ingots and to suppress the growth of columnar grains. In addition, for the last eight years a new generation of Al-Ti-C grain refiners has been used commercially in a wide range of alloy systems. This paper will compare the potency of the commercially available Al-5Ti-1B grain refiner with that of the Al-3Ti-0.15C grain refiner for the 6063 cast alloy. For more information, contact Gabriela Popescu, University Politehnica of Bucharest, Material Science and Engineering Faculty, Splaiuil Independentei 313, Bucharest, 77206 Romania. gabriella81us@yahoo.com.     

添加Cr元素对快速凝固Al-Ti-Fe基合金显微组织和显微硬度的影响

采用单辊旋铸技术制备Al-2．5Ti-2．5Fe和A1-2．5Ti-2．5Fe-2．5Cr合金薄带，利用X射线衍射、EDS、透射电镜和高分辨电镜来分析该两种合金的急冷态和退火态显微组织，研究了Cr对快速凝固Al-2．5Ti-2．5Fe合金显微组织和显微硬度的影响。     

Microstructure and thermal stability behavior of a rapidly solidified Al—Ti—Fe—Cr alloy

A rapidly solidified Al-2.5Ti-2.5Fe-2.5Cr(mass fraction in%) alloy was prepared by melt spinning.Asquenched and as-annealed microstructures were studied by X-ray diffractometry(XRD),transmission electron microseopy(TEM),high-resolution transmission electron microscopy(HREM) and energy dispersive spersive spectrum(EDS) analysis,The microhardness of the alloy at different annealing temperatures was measured.The results obtained indicate that the microhardness of the rapidly solidified Al-2.5Ti-2.5Fe-2.5Cr alloy does not vary with differnet annealing temperatures.The as-quenched microstructure of the alloy includes two kinds of dispersed primary phases:Al3Ti and Al13(Cr,Fe)2,After annealing at 400℃ for 10h,the stable phase Al13Fe4 appears in the microstructure.     

A novel fading-resistant Al-3Ti-3B grain refiner for Al-Si alloys

Al-Ti-B refiners with excess-Ti perform adequately for wrought aluminum alloys but inefficiently in the case of foundry alloys. The high content of silicon in the latter, which forms silicides with Ti and severely impairs the refining potency of the nuclei, is known to be responsible for the poor performance. Hence, new grain refiners, such as Al-3B and Al-3Ti-3B master alloys with excess-B have been developed with well documented advantages for Al-Si alloys. It is very desirable to involve TiAl₃ particles in the Al-3Ti-3B master alloy to maximize its grain refining efficiency. However, fading phenomenon is a key drawback for application of the TiAl₃-containing refiners in aluminum foundry. In the present work, new Al-3Ti-3B grain refiners, containing TiB₂, AlB₁₂ and TiAl₃ particles were developed with an aim to prolong the acting time after inoculation. The results showed that inoculation of Al-7Si alloy with thus meliorated Al-3Ti-3B grain refiner has produced a fine grain structure which was approximately maintained up to 30 min.     

MICROSTRUCTURE AND DUCTILITY OF RE DOPED RAPIDLY SOLIDIFIED NiAl

ＭＩＣＲＯＳＴＲＵＣＴＵＲＥＡＮＤＤＵＣＴＩＬＩＴＹＯＦＲＥＤＯＰＥＤＲＡＰＩＤＬＹＳＯＬＩＤＩＦＩＥＤＮｉＡｌ￥ＳＵＮＢａｏｄｅ;ＬＩＮＤｏｎｇｌｉａｎｇ;ＹＡＮＧＧｅｎｃａｎｇ;ＺＨＯＵＹａｏｈｅ１）ＳｈａｎｇｈａｉＪｉａｏＴｏｎｇＵｎｉｖｅｒｓ...     

中间合金对A356.2合金细化的效果

采用铝业协会制订的TP-1型标准测试法,对Al-10RE、Al-5Ti-1B、Al-5Ti-1B-10RE等中间合金对A356.2合金的细化效果进行评价,以优化铝合金轮毂制造过程中合金熔体细化处理工艺。结果表明, Al-5Ti-1B-10RE中间合金中的RE不仅可以有效抑制晶粒尺寸的衰退,而且在一定程度上改善Ti、B、Sr对A356.2合金显微组织的细化和变质效果;TP-1型晶粒度检测法是一种简单、直观、准确的中间合金细化效果在线评价方法。