曹利
,
蒋持平
,
姚忠凯
,
雷廷权
金属学报
在备有拉伸台的扫描电子显微镜上原位观察了V_f为22%的碳化硅晶须增强铝(SiC_W/Al)复合材料压铸态试样和T_6态试样的动态拉伸过程。结果发现外加应力达到180-190MPa时复合材料内部就已形成许多微裂纹,裂纹一般在晶须端部形成,其扩展亦有一定的规律。经过对复合材料简化模型的复变函数分析和计算,求出了晶须周围应力场,进一步通过塑性力学的分析,从理论上解释了本文所观察到的实验现象。
关键词:
复合材料
,
fracture
,
stress distribution
,
SiC whiskers
,
aluminum
邢琳琳
,
郑雁军
,
杨雯雯
,
邵明增
,
崔立山
,
卢贵武
腐蚀学报(英文)
研究了含Al量不同的HK40合金在工业纯Ar气氛中的高温抗氧化性能, 用SEM、XRD等方法检查了氧化膜的形貌、结构与成分. 结果表明, 加入铝后合金表面在高温下形成均匀的Al2O3膜, 从而提高了合金的高温抗氧化性能; Al加入量为6 mass%时, 合金的高温抗氧化性能最好. 在1100℃时加Al的合金氧化增重遵从抛物线规律, 且随Al含量的增加, 抗氧化性能显著增强. 随着合金中Al添加量的增加, 高温氧化膜组成相(Cr2O3、CrMn1.5O4、MnCr2O4、Al2O3) 中的Al2O3逐渐增加. 同时Al的存在提高了表面氧化膜的均匀性, 且氧化膜中的Fe、Ni含量远低于基体.
关键词:
HK40 合金
,
aluminum
,
oxide scale
,
high temperature oxidation resistance
梅天庆
,
鱼光楠
,
贺利敏
,
裴玉汝
中国腐蚀与防护学报
在摩尔比为2:1的AlCl3-[bmim]Cl离子液体中,加入一定量的甲苯,控制阴极电流密度,在基体铁片上获得银白色和平整致密的铝镀层。循环伏安实验表明离子液体中沉积铝源于Al2Cl7- 的还原,还原峰电位为-0.34 V;当电流密度为20 mA/cm2时,最大电流效率达97%;所得铝镀层的厚度与电镀时间呈抛物线关系;在电流密度小于 35 mA/cm2时,镀层厚度随电流密度增大呈逐渐递增趋势;扫描电镜、X射线能谱对铝镀层分析结果表明(45±2)℃ 温度得到平整致密纯度高的铝镀层;当电流密度为 20 mA/cm2时,铝镀层呈薄片状生长,随电流密度的增大,镀铝层形貌由片状向粒状过渡,并伴随着晶粒的细化。
关键词:
电沉积
,
ionic liquid
,
aluminum
,
thickness
,
current density
陈伟
,
李龙飞
,
杨王玥
,
孙祖庆
金属学报
利用Gleeble 1500热模拟试验机进行单轴热压缩实验, 研究了合金元素Al对过共析钢缓冷相变和
过冷奥氏体动态相变组织的影响.
结果表明: 在缓冷相变时, Al的加入抑制网状渗碳体形成, 细化珠光体
片层间距; 在过冷奥氏体形变过程中, 动态转变经历动态相变和相变所得珠光体中渗碳体球化及铁素体动
态再结晶等过程. 在动态相变过程中, 没有形成晶界网状渗碳体, 而直接产生珠光体.
Al的加入使动态相变过程中奥氏体的稳定性提高、珠光体转变推迟, 进一步细化了珠光体片层间距.
在相变所得珠光体中渗碳体球化及铁素体动态再结晶的过程中, Al阻碍渗碳体粗化, 使渗碳体颗粒和铁素体晶粒尺寸细化.
关键词:
过共析钢
,
undercooled austenite
,
aluminum
汪日志
,
夏立芳
材料研究学报
选取能量为80keV、剂量范围为1×10~(16)-8.3×10~(17)N~+·cm~(-2)的氮离子对L2,LD2,LF12,LY12,Al-4%Cu 等Al 合金进行氮离子注入,并用X 射线光电子能谱及透射电子显微镜分析了氮离子注入层的价态特征及组织结构特点。在此基础上进行了硬度及耐磨性试验。氮离子注入到Al 及Al 合金中在室温下能形成细小弥散的AlN 析出相;氮离子注入加速了Al-4%Cu 合金的时效析出过程。Al 及Al 合金表层硬度及耐磨性随着氮离子注入剂量的增加而提高。
关键词:
离子注入
,
aluminum
,
wear
Journal of Materials Science
In situ particle reinforced Al-4.5Cu/TiB2 composite was fabricated with TiO2, H3BO3, Na3AlF6 powders and Al-4.5Cu alloy by reaction in melt. The composite can be directly casted into moulds to make composite parts. TiB2 particles distribute uniformly in the matrix. The average size of TiB2 particles is 0.93 mum. At the atomic scale, TiB2 is hexagonal, and exhibits hexagon or quadrilateral shape. The orientation relationships exist in the interfaces between TiB2 particle and alpha -Al, and between the reinforced small Al2Cu phase and alpha -Al in the composite. They are [0-332](T)iB // [110](<)alpha>-Al, (01-11)(T)iB // (002)(<)alpha>-Al and [-1-32](<)alpha>-Al // [123](A)lCu, (211)(<)alpha>-Al // (111)(A)lCu. TiB2 particle is nucleation site for alpha -Al matrix growth in the composite. The interface between TiB2 particles and the matrix is clean and well bonded. No reaction product has been found through HREM observation. This is beneficial to the strength of the composite. The as-cast Al-4.5Cu/TiB2 composite exhibits mechanical excellent properties: the tensile strength is 416.7 MPa, the yield strength is 316.9 MPa, and the elongation is 3.3 pct.
关键词:
aluminum
G.Y. Lin
,
Z.F. Zhang
,
H. Zhang
,
null
,
null
金属学报(英文版)
The hot deformation behaviors and microstructures of Al-Zn-Mg-Cu-Cr aluminum alloy during hot deformation have been studied using thermal stimulation test, optical microscopy and transmission electron microscopy. As a result, the true stress vs. true strain cures and the microstructures of various deformation conditions are obtained; the microstructures gradually incline to dynamic-recrystallization with the deformation temperature rising and the recrystallization grains refine with the decrease of deformation temperature or with raising the strain rates; the quantitative relationship between the Zener-Hollomon parameter (Z) and average recrystallization grain size in the subsequent heat treatment is set up.
关键词:
Al-Zn-Mg-Cu-Cr aluminum alloy
,
aluminum
,
alloy
,
Hot
,
deform
Z. Zhou
,
Q.S. Gan and P.D. Ding College of Materials Science and Engineering
,
Chongqing University
,
Chongqing 400044
,
China
金属学报(英文版)
The reduction of the volumes of the silica glass during aluminum reactive penetration was observed experimentally. The liquid aluminum infiltrates easily into the cavities while the released silicon solves in the liquid aluminum, and Al/A1_2 O_3 composites could be obtained finally. The experimental result has shown that Al/A1_2 O_3 composites could transform into A1_2O_3 grains by oxygen in the cavities of Al/A1_2O_3 composites during longer penetration treatment. The formation of alumina is a sintering process, in which liquid aluminum, particulate alumina and oxygen play an important role. Tin nsformed process has shown that there is a relationship of σAl_2O_3
关键词:
aluminum
,
null
,
null
,
null
,
null
F.H. Froes(IMAP
,
University of Idaho
,
Moscow
,
ID 838443026
,
USA Manuscript received 26 August 1996)
金属学报(英文版)
The synthesis, processing and mechanical properties of the light metals, aluminum,magnesium and titanium Produced by advanced techniques are reviewed. Synthesis techniques to be addressed will include rapid solidification, spray deposition, mechanical alloying, plasma Processing and vapor deposition.
关键词:
:synthesis/processing
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null