异步轧制速比对高纯铝箔织构转变的影响

采用不同速比对高纯铝板进行异步冷轧,并将冷轧样品进行不同温度和时间的再结晶退火,研究异步轧制速比对高纯铝箔织构转变的影响。结果表明:高速比的异步轧制在样品中产生较强的旋转立方织构和{102}〈uvw〉织构,异步轧制退火后的高纯铝箔样品具有很强的立方织构{001}〈100〉。立方织构的体积分数与速比和温度有关:当速比为1.06时,温度升至300℃开始出现立方织构;当速比为1.17时,温度升到200℃就出现立方织构。立方织构组分的形成存在一个阈值温度,此温度与异步轧制的速比成反比,随着速比的增加,阈值温度逐渐降低,这与异步轧制提高高纯铝箔的形变储能有关。异步轧制有利于在低温时形成较强的立方{001}〈100〉织构。     

高纯铝箔在异步轧制和再结晶过程中取向的演变

采用不同速比的异步轧制技术对99.99%的高纯铝板进行不同形变量的冷轧,并对冷轧样品进行不同温度和时间的再结晶退火.利用X射线衍射技术和TEM观测探讨了异步轧制条件下高纯铝箔中变形织构和再结晶织构的演变.结果表明:高速比的异步轧制(i=1.28)在样品中产生相对较强的旋转立方织构{001}(110).异步轧制后退火的高纯铝箔样品中,立方{001}(100)织构组分的再结晶晶核的形成和长大存在一个临界转变温度,此温度与异步轧制的速比成反比.异步轧制有利于降低高纯铝箔的再结晶温度,这与异步轧制提高高纯铝箔的形变储能有关.异步轧制有利于在低温时形成强的立方{001}(100)织构组分,但此时漫散较大;随着退火温度的升高,漫散范围明显缩至8°-10°.     

Ce对铝箔再结晶织构演变规律的影响

以高纯铝箔和不同Ce含量的稀土铝箔为研究对象,运用EBSD技术对高纯铝箔与稀土铝箔冷轧后及不同温度再结晶退火后的织构进行分析,研究再结晶退火过程中织构的演变规律和稀土Ce对铝箔织构的影响。结果表明:轧制总变形率为96%的铝箔,织构以铜型织构、R型织构和一些S织构为主。随最终退火温度的升高,立方织构占有率快速增长。少量稀土元素的加入有利于再结晶退火后立方织构的形成。     

稀土铝箔再结晶退火组织、织构研究

将含w(Ce)=11.45%的Al-Ce中间合金按照一定的比例加入到高纯铝液中,制备成不同稀土含量的稀土铝锭,经过均匀化退火、热轧、冷轧,获得0.11mm厚铝箔。研究稀土含量、再结晶退火工艺对铝箔组织、织构的影响。结果表明,添加适量稀土元素Ce可以细化铝箔的再结晶晶粒,提高再结晶退火后铝箔的立方织构占有率;含w(Ce)=0.0048%的稀土铝箔530℃10 min再结晶退火时立方织构含量最高。     

中间退火对Ni-7at%W合金基带再结晶织构的影响

采用真空电磁搅拌电弧熔炼制备的Ni-7at%W合金初始锭,经热锻、热轧、大形变量冷轧和最终再结晶退火制备出100 μm厚合金基带。采用X光衍射技术（XRD）和电子背散射衍射技术（EBSD）研究轧制过程中的中间退火处理对再结晶织构的影响。结果表明,提高中间退火次数可以削弱轧制织构α取向线上的取向强度,提高β取向线上的取向强度,促进轧制组织中立方取向晶核的形成,消除再结晶过程中晶粒异常长大现象,最终提高再结晶立方织构的份额。     

中间退火对高纯铝箔立方织构的影响

:采用晶体取向分布函数 (ODF)研究和分析了中间退火对高纯铝箔立方织构的影响。研究结果表明 ,中间退火对高纯铝箔冷轧形变织构影响不大 ,但对成品退火箔材中立方织构和R织构含量产生重要影响 ,在 30 0℃× 2h中间退火条件下 ,成品箔材中再结晶立方织构取向密度最大 ,R织构比例较小。其作用机理是中间退火影响铁的存在状态 ,导致成品退火时影响原位再结晶和不连续再结晶过程     

异步轧制高纯铝箔在退火过程中织构的演变

采用异步轧制技术对高纯铝箔进行冷轧,利用加热和在冷水中淬火,把样品的高温态保存下来。通过ODF分析和反极图定量计算,对高纯铝箔微取向流变行为进行了研究。结果表明:立方织构{001}<100>是在再结晶退火过程中形成和发展的;适宜的速比,相应的形变量和与之相匹配的退火工艺,是获得强立方织构{001}<100>的前提。根据形变与再结晶理论,探讨了异步轧制高纯铝箔中立方织构{001}<100>的形成和发展。     

初始晶粒尺寸和预先回复对激光加热下Cu再结晶织构的影响

分别对不同初始晶粒尺寸的冷轧及冷轧后经回复的纯Ｃｕ进行了激光超快速加热再结晶处理。发现细晶冷轧样品完全再结晶时其织构由立方与冷轧织构组分构成,而粗晶样品为单一的立方织构;经低温回复的样品再结晶后的立方织构强度明显高于未经回复的样品。冷轧样品经短时（≤１１．２５ｍｓ）激光加热。金相组织仍呈冷轧状态,而冷轧织构强度显著降低,未发现立方强构增强。分析认为,在激光加热条件下,再结晶初期各取向晶粒形核机会都     

退火温度对无取向硅钢再结晶行为的影响

使用EBSD和XRD技术研究了1.3%Si无取向硅钢在不同退火温度条件下的微观组织、宏观织构和微观取向。分析了退火温度对此成分体系无取向硅钢再结晶组织和织构的影响;讨论了退火温度与无取向硅钢成品板磁性能的关系。实验结果表明:无取向硅钢的退火温度对其再结晶组织和成品板铁损值有影响,随着退火温度的上升,再结晶晶粒平均尺寸增大且铁损值下降。γ纤维织构是再结晶织构中的优势组分,高斯{110}100织构强度也较高。退火温度对再结晶织构也有影响,随着退火温度上升,γ织构的含量不断上升,其中{111}121织构强度高于{111}110织构强度;退火温度的上升降低了立方{100}100织构和旋转立方{100}110织构但增加了高斯{110}100织构的强度,高斯织构的强度在870℃时达8.8。高斯取向晶粒主要在{111}121取向晶粒附近出现,旋转立方取向晶粒主要出现{111}110取向晶粒附近。由于{111}面织构强度增加和立方织构、旋转立方织构强度的降低,随着退火温度的上升,无取向硅钢的磁感应强度下降。     

柱状晶对Fe-3%Si电工钢再结晶织构演变规律的影响

在对长轴分别平行于板法向(ND)、轧向(RD)、横向(TD)的柱状晶样品冷轧组织及织构演变规律分析的基础上,利用XRD与EBSD技术,对不同退火温度下各样品再结晶织构的形成规律进行分析.结果表明,柱状晶样品再结晶织构的演变,一方面体现了初始取向晶粒的"遗传性",即立方织构与Goss织构的形成;另一方面又展示了柱状晶样品不同于单晶及多晶的"特殊性",即{113}织构的形成、Goss晶粒大大超过立方晶粒的生长能力及TD样品中{110}〈110〉取向晶粒的消失.退火温度的变化在不同样品中可造成立方织构的增强或减弱,这取决于再结晶时的形核及长大环境,分析认为TD样品低温时形成最强的立方织构与其在冷轧过程中最强的晶界阻力有关.综合考虑各再结晶织构的转变规律,其形成与定向形核及定向长大均相关.研究还证实,3种柱状晶样品中等压下量冷轧并退火后都可抑制γ线织构的形成.     

Effect of trace yttrium on cube texture of high-purity aluminum foils

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Texture transformations upon annealing of aluminum foils: I. Strong texture components

Pole figures have been constructed and textures have been compared for aluminum foils from various manufacturers in the as-delivered state and after additional annealings. Difference in the orientations of the basic texture components have been revealed in annealed foils. The main type of the transformation of a texture upon annealing is the development of a texture component {001}〈100〉 whose orientation differs fundamentally from the basic texture components observed in the foil prior to annealing. In another type of texture transformations, new texture components close to the basic orientations of the deformation texture are developed along with the {001}〈100〉 orientation. In the case of a third type of texture transformations, along with the orientation {001}〈100〉 which is formed upon recrystallization, the major part of the basic deformation-texture components are retained. The orientations of the basic texture components that are formed upon annealing belong to fields of allowed orientations of the basic texture components that were present in the foil before annealing. Apart from regions with a high pole density, regions with a moderate pole density have been found in the pole figures of annealed foils.     

Recrystallization behavior of high purity aluminum at 300 °C

The recrystaliization behavior of 98.5% cold rolled high purity aluminum foils annealed at 300 °C was investigated, and the evolution of the microstructures was followed by electron back scattered diffraction(EBSD). The results show that the recrystaliization process of the high purity aluminum foils at 300 °C is a mixture of discontinuous- and continuous-recrystallization. The orientations of the recrystaliization nuclei include not only the cube orientation, but also other orientations such as some near deformation texture components which are the results of strong recovery process. However, such continuously recrystallized grains are usually associated with relatively high free energy, so they would be consumed by the discontinuously-recrystallized grains (cube-oriented grains) in subsequent annealing. On the other hand, the pattern quality index of recrystallized grains shows dependence on the crystal orientation which might introduce some errors into evaluating volume fraction of recrystaliization by integrating pattern quality index of EBSD.     

LF6铝合金搅拌摩擦点焊

搅拌摩擦点焊(FSSJ)是近年来发明的新的点焊方法,具有接头强度高、能耗低和设备简单等优点,在汽车行业焊接轻质合金如铝合金、镁合金等具有很好的应用前景.采用自行设计的搅拌头对1 mm 1 mm的LF6铝合金进行了搅拌摩擦焊试验研究.试验结果表明,接头剪切强度约是电阻点焊的1.56倍.接头可以分为搅拌区和热影响区,搅拌区的材料受到搅拌头的作用发生圆周运动和轴向运动,形成细小的再结晶晶粒,强度高、塑性好.     

Formation of recrystallization cube texture in high purity face-centered cubic metal sheets

An investigation on recrystallization textures in high purity face-centered cubic (fcc) aluminum, copper, and nickel indicated that the cube texture is a unique dominant final texture. In a macroview of rolling deformation, a balanced activation of four slip systems can result in certain stability of some substructure with cube orientation in the deformed matrix. In the stable substructure the dislocation density is very low, and the dislocation configuration is rather simple in comparison to other orientations so that the cube substructure can easily be transformed into cube recrystallization nuclei by a recovery process. A high orientation gradient and correspondingly high angle boundaries to the deformed matrix are usually expected around the cube nuclei, which, therefore, grow rapidly. After the primary recrystallization, the size of cube grains is much larger than the grains with other orientations, which will be expensed as the cube grains grow further, so that the cube texture can finally become a dominant texture component.     

超快速加热退火下保温时间对5083铝合金组织及力学性能的影响

利用Gleeble-3500热模拟系统和电子背散射衍射(EBSD)技术对5083铝合金超快速退火组织的演变规律进行了研究,探讨了5083铝合金经过80％冷轧变形后以500℃/s加热至450℃时,不同保温时间(1～60 s,冷却速度40℃/s)对退火组织及力学性能的影响.结果表明,随退火保温时间从1 s延长到60 s,5...     

Strengthening and stress drop of ultrafine grain aluminum after annealing

Ultrafine grain pure aluminum was produced by equal channel angular pressing and cold rolling,the deformed aluminum was annealed at 200 °C for 1 h.The tensile curves of deformed and annealed aluminum show that yield strength of deformed aluminum increases by 100%-300% and its elongation decreases by about 20%.After low temperature annealing,strength of annealed aluminum increases by 20% and elongation decreases by over 50%,the recovery of dislocations may be the main cause of annealing strengthening.In addition,there is an abrupt stress drop in the tensile curves of annealed aluminum and the formation of shear band is responsible for it.     

电解电容器高压阳极用铝箔研究

研究了电解电容器高压阳极用高纯铝的纯度及各种工艺因素对箔材退火后组织的影响，重点研究了铝的纯度，均匀化制度，热轧温度，冷轧及中间退火对最终退火后箔材形成立织构的影响，选择的较佳工艺条件，在工艺技术和产品质量上取得了较大进展，满足了用户的使用要求，替代了进口箔。