Cu—Zn—Al合金逆形状记忆组织的电镜观察

用透射电镜观察了Cu-Zn-Al合金中逆形状记忆的贝氏体组织。在外加约束应力作用下,逆记忆量可以提高一个数量级,贝氏体片侧相界面的抛物线轮廓和贝氏体片交叉曲折的现象说明了贝氏体展宽是扩散控制的切变过程。     

淬火在Cu—Zn—Al合金马氏体中引入的一种新缺陷

本文报道了Cu-Zn-Al合金中18R马氏体里存在的一类新的面缺陷。实验结果的统计表明,在由高温直接淬入冰水中的样品里,马氏体中常出现非基面上的层错。衍衬分析证明,这种层错常位于(125)_M面上。通过对晶体结构和处理条件分析,提出了这种层错出现的机制,并给出了层错的结构模型。     

仪表用Al—Cu—Zn—Mg合金的双级时效

本文研究了Al-5.5Cu-4.5Zn-0.8Mg合金挤压棒经过465℃淬火后再以不同的时效制度处理,合金组织和性能变化的规律.固溶处理后合金组织中存在着较多的未溶相质点;时效时在α相基底上形成脱溶物晶核的同时,未溶相质点作为脱溶过程中化合物析出依附物而长大,在采用120℃/6小时 150℃/14小时双级时效制度的情况下,脱溶物质点的总数要比采用130℃/20小时时效的多一些.130℃时效时,合金强度(σ_b)最多能够达到382兆帕,而双级时效后σ_b最大值为404兆帕,平均值约为398兆帕,高于技术条件的要求值.     

Cu—Zn—Al合金中温相变产物的组织和结构

测定了Cu-27.27 Zn-3.73 Al Wt-%合金直接从高温母相淬火至中温的等温转变曲线.用金相、X-射线和电镜对直接淬火和从DO_3有序母相上淬至中温的转变产物做了形貌与结构的观察和分析.实验表明,依照转变产物,可将两个分离相接的c曲线分为三个区间:棒状α相,α相与片状贝氏体的混合组织,片状贝氏体.上淬所形成的贝氏体与直接淬火的贝氏体形貌相同.随时效时间的延长,贝氏体逐渐变成α相,它与从母相平衡析出的α相的点阵常数没有差别,由B2和DO_3母相所形成的贝氏体为接近正交的长周期结构,而且DO_3母相所形成的马氏体为单斜结构,它们分别对应(1210)与(2010)衍射峰的重叠和分离,表示前者的有序度较低.     

Al—Pb—Cu减摩合金的热处理

本文采用正交多项式回归分析等方法,考察了Al-Pb-Cu合金在T_4、T_6和自淬火等热处理工艺中性能的变化,获得了最佳热处理工艺参数以及抗拉强度、延伸率与时效温度和时间的关系式。     

合金元素对Al—Cu合金热裂倾向的影响

为寻求一种低热裂倾向的高强韧造铝合金材料,研究了Cu,Zr和V3种元素对Al-Cu合金热裂倾向的影响,结果表明,V明显降低材料的热裂倾向;Zr含量低时轻微增大合金的热裂倾向,含量高时强烈增大热裂倾向,在4．5％－5．5％范围内Cu增大热裂倾向,Zr和V对合金热裂倾向的不同影响在于V主要存在于晶内,而Zr则部分存在于晶界。     

熔融NaF—AlF3体系活度的测定

用Ｎａ（Ａｌ）｜Ｎａ＾＋β－Ａｌ２Ｏ３｜（α＋β）－Ａｌ２Ｏ３电池测量了与ＮａＦ－ＡｌＦ３体系平衡的Ａｌ中Ｎａ活度，椐此计算了该二元系中ＮａＦ和ＡｌＦ３的活度。随熔体中分子比增加或温度升高，ＮａＦ的活度增大，ＡｌＦ３的活度减小。     

机械合金化法制备Al—Cu—Fe纳米非晶合金

采用行星式高能球磨机制备了Al80-xCuxFe20(x=20-40）三元非晶纳米合金粉末,分析了不同球磨时间及热处理工艺对粉末结构、颗粒大小等的影响。结果表明：成分为Al40Cu40Fe20的粉末球磨时逐步非晶化,球磨33h后,非晶化程度最大,最小颗粒尺寸达到5．6nm;进一步球磨,非晶晶化,颗粒尺寸增大;成分为Al80-xCuxFe20(x=20,25,30)的粉末球磨90h后,得到非晶,最小颗粒尺寸为3．4nm。球磨制备的Al-Cu-Fe非晶粉末具有铁磁性。用DSC测量了其晶化温度（Tc),Tc≈873℃。     

DETERMINATION OF ACTIVITY OF AI IN SOLID Cu-Al ALLOYS

Activities and activity coefficients of Al in solid Cu-AI alloys have been determined by meansof solid electorlyte galvanic cells Al(a_1 , in alloy), Al_2O_3 | ZrO_2· Y_2O_3 | Ni, NiOand Al(a_1 , in alloy), Al_2O_3 | Na, βAl_2O_3 | Al(a_2 , in alloy), Al_2O_3     

ACTIVITY OF In IN LIQUID In-Bi-Tl ALLOYS

The activities of In in two pseudo-binary systems of fixed molar fraction ratio N_(Bi)/N_(Ti) have been measured by means of EMF method using zirconia solid electrolyte gal- vanic cells over the temperature range of 973—1223 K.The excess free energies were deter- mined based on the experimental data.The experimentally determined thermodynamic prop- erties of the ternary alloys agree well with the values caleulated from the author's equations using related binary data.The excess free energies are negative in almost all compositions ex- cept those near the In-Tl side and become negatively larger as the compositions approach the Bi-Tl side.     

RHEOLOGICAL PROPERTIES OF SEMI-SOLID Al-Si ALLOY IN SOLID-LIQUID ZONE

ＲＨＥＯＬＯＧＩＣＡＬＰＲＯＰＥＲＴＩＥＳＯＦＳＥＭＩＳＯＬＩＤＡｌＳｉＡＬＬＯＹＩＮＳＯＬＩＤＬＩＱＵＩＤＺＯＮＥ①ＣｈｅｎＸｉａｏｙａｎｇ，ＭａｏＷｅｉｍｉｎ，ＺｈｏｎｇＸｕｅｙｏｕＳｃｈｏｏｌｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎ...     

熔融NaF－AlF_3体系活度的测定

用Ｎａ（Ａｌ）｜Ｎａ~＋β－Ａｌ２Ｏ３｜（α＋β）－Ａｌ２Ｏ３电池测量了与ＮａＦ－ＡｌＦ３体系平衡的Ａｌ中Ｎａ活度，据此计算了核二元系中ＮａＦ和ＡｌＦ_３的活度，随熔体中分子比增加或温度升高，ＮａＦ的活度增大，ＡｌＦ_３的活度减小．     

MICROSTRUCTURE STUDY OF CONSTITUENT PHASES IN 2024 SERIES Al ALLOYS

X-ray microanalysis,convergent beam electron diffraction(CBD)and selected area electrondiffraction(SAD)studies on the structures and compositions of the constituent phases in2024 series Al alloys have been conducted.Partial substitution of alloying elements is found tooccur in all the constituent phases,which cause small deviations from the stoichiometric com-positions reported in these ternary compounds.The dominant phase is α-Al_(12)(FeMn)_3Si whichhas a body center cubic crystal structure with the Im■ space group and a=1.25 nm.The nextdominant phase is Cu_2FeAl_7 which has a primitive tetragonal crystal structure with theP4/mnc space group and a=0.6336 nm,c=1.487 nm.The minor phase is α'-Al_(12)Fe_3Si hav-ing α primitive cubic crystal structure with the Pm■ space group and α=1.27 nm.     

2024系列铝合金粗大夹杂相的微观结构研究

本文利用X射线能谱分析、会聚束电子衍射和常规电子衍射对2024系列铝合金粗大夹杂相的结构类型和成分进行了研究。所有夹杂相的合金元素均部分地被其它元素所取代,使粗大夹杂相的成分稍偏离于理想的三元化合物。粗大夹杂相中含量最多的是体心立方α-Al_(12)(FeMn)_3Si,空间群为Im 3,点阵常数α=1.25nm;其次是Cu_2FeAl_7,空间群为P4/mnc,点阵常数α=0.6336nm,c=1.487nm;还有少量的属简单立方的α-Al_(12)Fe_3Si,空间群为Pm 3,点阵常数α=1.27nm。     

Al液中溶解态La活度的研究

以多晶La_(0.95)Ca_(0.05)F_(2.95)作固体电解质,LaNi_5-Ni合金作参比电极,Mo丝作电极引线,组成稀土La传感器,直接测定了1023K时Al液中不同La浓度时溶解态La的活度其结果与用氧探头测定的氧浓差电动势的变化规律相符合,遵从La的脱氧平衡规律同时还获得了1023K时Al-La稀溶液体系中有关的热力学数据: △G_(La)=-175.2kJ/mol,γ_((La)(s))=5.85×10~(-7) ε_(La)~(La)=28.7,e_(La)~(La)=0.024     

INTERNAL OXIDATION KINETICS & DIFFUSION MECHANISM OF OXYGEN IN Cu-Al SINTERED ALLOY

In this paper, internal oxidation kinetics and the diffusion mechanism of oxygen in sintered Cu-Al alloy have been studied by means of scanning electron microscopy,transmission electron microscopy and heat-weighting scales. The results show that the kinetic curves obey the parabolic law in the initial stage and are linear in the late stage.The oxygen atoms are mainly transported in the from of grain boundary diffusion and volume diffusion in the process of internal oxidation. The plastic deformation of Cu matrix around oxide particles increases the probability of [O] atoms moving in accordance with dislocation diffusion mechanism. Meanwhile, the activation energy and diffusion coefficient in the process of internal oxidation are evaluated by means of kinetic method so as to obtain the velocity equations of reacting interface moving in different stage.     

SUPERPLASTICITY AND SOLID STATE BONDING OF TITANIUM ALLOYS

1.IntroductionItisknownthatsuperplasticity(SP)exertsafavourableeffectonthesolidstateweldabilityoftitaniumalloys[1--31.IthasbeenalsoestablishedthattheacceleratedsolidstatejointformationisdeterminedbytheinfluenceofthebasicmechanismofSPdeformationgrainboundarysliding(GBS).However,thecitedinvestigationswereconductedatrelativelyhightemperatures(~0.7Tin)whenthediffusivityoftitaniumalloysisconsiderable.Atthesametimeitisknown,thatthetemperaturerangeofsuperplasticitysubstantiallydependsonthemeangra…     

In-Bi-Tl三元系液体合金中成分的活度测定SCIEI

用ZrO_2固体电解质组成氧浓差电池:(-)Re,In,In_2O_3|ZrO_2(Y_2O_3)|In-Bi-Tl,In_2O_3,Re(+),在973—1223K的温变范围内测定了In-Bi-Tl三元系中含Tl量较少的两个mol比(N_(Bi)/N_(Tl))一定的拟二元系合金中In的活度,据实验结果求得合金的过剩自由能。使用作者曾提出的计算式及有关各二元系热力学数据计算了合金中In的活度及过剩自由能。计算值与实验值相当一致。此三元系合金的过剩自由能除在In-Tl二元系相近组成以外都呈负值,极小值在Bi-Tl二元系上。