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三维板料成形过程的显式有限元分析 被引量:2
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作者 李光耀 《计算结构力学及其应用》 CSCD 1996年第3期253-268,共16页
本文采用基于随动坐标系的假定应变域壳单元及显式有限元格式求解三维板料成形问题。板材料服从Hil各向异性弹塑性准则,板料与模具之间的接触界面由主仆面接触搜寻法处理,接触力由罚参数法计算。文中给出了几个三维成形过程的计算... 本文采用基于随动坐标系的假定应变域壳单元及显式有限元格式求解三维板料成形问题。板材料服从Hil各向异性弹塑性准则,板料与模具之间的接触界面由主仆面接触搜寻法处理,接触力由罚参数法计算。文中给出了几个三维成形过程的计算实例。数值算例表明,本文方法具有较高的计算精度和计算效率。 展开更多
关键词 冲压成形 壳体 接触 有限元
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板料成形有限元分析的显式算法 被引量:19
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作者 吴勇国 李沿健 +1 位作者 李志刚 肖景容 《塑性工程学报》 CAS CSCD 1995年第3期31-36,共6页
本文基于连续介质力学及有限变形理论,建立了退化四节点壳单元的动力有限元模型,用于三维板料成形过程分析。数学模型采用物质坐标系中的UpdateLagrange描述,用动力显式积分的方法,使位移计算显式化,避免了由材料几... 本文基于连续介质力学及有限变形理论,建立了退化四节点壳单元的动力有限元模型,用于三维板料成形过程分析。数学模型采用物质坐标系中的UpdateLagrange描述,用动力显式积分的方法,使位移计算显式化,避免了由材料几何等高度非线性引起的计算收敛问题。根据此模型编制的程序模拟了一盒形零件的成形过程。 展开更多
关键词 板料 有限元 冲压成形 显式算法
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包套轧制制备TiAl基合金板材 被引量:26
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作者 张俊红 黄伯云 +4 位作者 周科朝 李志友 何双珍 刘咏 贺跃辉 《中国有色金属学报》 EI CAS CSCD 北大核心 2001年第6期1055-1058,共4页
采用包套轧制技术 ,在 10 5 0℃制备了 2 .7mm厚的TiAl基合金薄板。金相观察表明 ,薄板具有均匀、细小的组织 ,平均晶粒尺寸约为 3μm。利用模拟平面应变实验研究了外加包套对TiAl基合金轧制时流变行为的影响 ,揭示了包套轧制提高TiAl... 采用包套轧制技术 ,在 10 5 0℃制备了 2 .7mm厚的TiAl基合金薄板。金相观察表明 ,薄板具有均匀、细小的组织 ,平均晶粒尺寸约为 3μm。利用模拟平面应变实验研究了外加包套对TiAl基合金轧制时流变行为的影响 ,揭示了包套轧制提高TiAl基合金热加工性能的机理。结果表明 ,包套轧制可以降低TiAl基合金变形时的流变应力 ,延缓流变软化趋势 ,降低局部流变系数 ,从而提高TiAl基合金的塑性变形能力。 展开更多
关键词 TIAL基合金 板材 包套轧制 塑性变形
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Theoretical analysis of the velocity field, stress field and vortex sheet of generalized second order fluid with fractional anomalous diffusion 被引量:27
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作者 徐明瑜 谭文长 《Science China Mathematics》 SCIE 2001年第11期1387-1399,共13页
The velocity field of generalized second order fluid with fractional anomalous diiusion caused by a plate moving impulsively in its own plane is investigated and the anomalous diffusion problems of the stress field an... The velocity field of generalized second order fluid with fractional anomalous diiusion caused by a plate moving impulsively in its own plane is investigated and the anomalous diffusion problems of the stress field and vortex sheet caused by this process are studied. Many previous and classical results can be considered as particular cases of this paper, such as the solutions of the fractional diffusion equations obtained by Wyss; the classical Rayleigh’s time-space similarity solution; the relationship between stress field and velocity field obtained by Bagley and co-worker and Podlubny’s results on the fractional motion equation of a plate. In addition, a lot of significant results also are obtained. For example, the necessary condition for causing the vortex sheet is that the time fractional diffusion index β must be greater than that of generalized second order fluid α; the establiihment of the vorticity distribution function depends on the time history of the velocity profile at a given point, and the time history can be described by the fractional calculus. 展开更多
关键词 generalized second order fluid fractional calculus anomalous diffusion stress field vortex sheet generalized Mittag-Leffler function
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高铌钛铝基合金板材的高温包套轧制 被引量:19
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作者 缪家士 林均品 +2 位作者 王艳丽 林志 陈国良 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2004年第4期436-438,共3页
采用高温包套轧制方法在普通轧钢轧机上首次成功的轧制出厚度为2.6 mm的高铌钛铝基合金板材。合金在轧制中的总变形量达到70%。板材表面质量良好,显微组织观察表明合金在轧制中发生了再结晶,但是变形后的组织并没有由于再结晶而明显细... 采用高温包套轧制方法在普通轧钢轧机上首次成功的轧制出厚度为2.6 mm的高铌钛铝基合金板材。合金在轧制中的总变形量达到70%。板材表面质量良好,显微组织观察表明合金在轧制中发生了再结晶,但是变形后的组织并没有由于再结晶而明显细化。这主要是由于合金在轧制回炉保温和轧后随炉冷却过程中,长时间停留在高温区间,导致了合金晶粒的长大。 展开更多
关键词 高铌钛铝合金 高温包套轧制 板材
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复合地基工后沉降的薄板变形模拟 被引量:10
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作者 饶为国 赵成刚 《应用力学学报》 CAS CSCD 北大核心 2002年第2期133-136,共4页
在桩 网复合地基中 ,如何考虑“网 桩 土”体系的共同作用而计算其沉降量 ,是一个值得研究的新问题 ,目前国内外均没有合适的计算方法。本文的新思路是 :以平板模拟网单元 ,基于薄板大挠度变形理论 ,结合桩 网复合地基的具体情况 ,... 在桩 网复合地基中 ,如何考虑“网 桩 土”体系的共同作用而计算其沉降量 ,是一个值得研究的新问题 ,目前国内外均没有合适的计算方法。本文的新思路是 :以平板模拟网单元 ,基于薄板大挠度变形理论 ,结合桩 网复合地基的具体情况 ,提出路基工后沉降量的直线计算方法 ,并给出工程算例。分析表明 。 展开更多
关键词 桩-网复合地基 路堤荷载 网单元 薄板 大挠度 工后沉降
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新型液压成形技术的研究进展 被引量:26
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作者 徐勇 张士宏 +1 位作者 马彦 陈大勇 《精密成形工程》 2016年第5期7-14,共8页
针对我国航空航天、汽车及核电等关键领域对精密零部件的迫切需求,以及目前液压成形技术应用中遇到的常见问题和缺陷,提出研发针对异形空心零件的脉动液压成形技术,和适用于复杂曲面薄壁板类零件的高能率冲击液压成形技术。分别从技术... 针对我国航空航天、汽车及核电等关键领域对精密零部件的迫切需求,以及目前液压成形技术应用中遇到的常见问题和缺陷,提出研发针对异形空心零件的脉动液压成形技术,和适用于复杂曲面薄壁板类零件的高能率冲击液压成形技术。分别从技术原理、成形机制、工艺设备和应用领域等方面进行了阐述和介绍。研究结果表明,两种新型液压成形技术能够充分发挥控形与控性一体化的优势,避免成形过程中的材料失稳和产品缺陷,显著提高管材和板材的成形能力和成形质量,未来有望在汽车和航空领域得到更为广泛的应用。 展开更多
关键词 管材 板材 脉动液压成形 高能率冲击液压成形 成形能力
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动物胶原纤维与植物纤维复合抄片结构的研究 被引量:22
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作者 付丽红 齐永钦 《皮革科学与工程》 CAS 1999年第4期13-17, ,共5页
将皮革固体废弃物制成的动物胶原纤维浆与植物纤维浆抄片,利用扫描电镜(SEM) 对抄片结构进行了观察、拍照与分析。
关键词 植物纤维 动物胶原纤维 复合抄片 结构 皮革废弃物
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EFFECTS OF SPECIFIED BLANK SIZE ON BODY WRINKLING DURING HYDRODYNAMIC DEEP DRAWING OF TAPERED RECTANGULAR BOX 被引量:21
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作者 L. H. Lang, D. C. Kang, S. H. Zhang, Z. R. Wang, S. J. Yuan, K. B. Nielsen and J. Dancket 1) Department of Materials Engineering, Harbin Institute of Technology, Harbin 150001, China 2) Aalberg University, Denmark 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第2期476-480,共5页
In this paper, the forming features of tapered rectangular box during hydrodynamic deep drawing are studied by means of FEM.The effect rules of square blank corner corner amount on body wrinkling are recognized and co... In this paper, the forming features of tapered rectangular box during hydrodynamic deep drawing are studied by means of FEM.The effect rules of square blank corner corner amount on body wrinkling are recognized and corresponding methods are discussed. At last, the results of FEM are verified by experi- ment. 展开更多
关键词 sheet metal forming hydrodynamic deep drawing FEM
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The Instability of the Vortex Sheet along the Shear Line 被引量:21
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作者 高守亭 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第4期525-537,共13页
The traditional Kelvin-Helmholtz notion of studying the shear instability is not suitable for the case associated with shear line with the strong wind shear in the vortex sheet. Since then, the shear instability becom... The traditional Kelvin-Helmholtz notion of studying the shear instability is not suitable for the case associated with shear line with the strong wind shear in the vortex sheet. Since then, the shear instability becomes theinstability of the vortex sheet. If the velocity is induced by the vortex sheet, the inequalities (1? R r + Ri d)> 0 and U(v,t)> U(A(t)) become the criterion of the vortex sheet instability. This criterion indicates that 1) the disposition of environment field restrains the disturbance developing along the shear line. 2) There exist multi—scale interactions in the unstable process of the shear line. The calculation of the necessary condition for the instability is also presented in this paper. Key words Shear line - Induced velocity - Instability of the vortex sheet This work was supported by the project on the study of the formative mechanism and predictive theory of the significant climate and weather disaster in China under Grant G 1998040907 and by the key project on the Dynamic Study of Severe Mesoscale Covective Systems sponsored by the National Natural Science Foundation of China under Grant No.49735180. 展开更多
关键词 Shear line Induced velocity Instability of the vortex sheet
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Trend of mass change in the Antarctic ice sheet recovered from the GRACE temporal gravity field 被引量:22
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作者 LUO ZhiCai LI Qiong +1 位作者 ZHANG Kun WANG HaiHong 《Science China Earth Sciences》 SCIE EI CAS 2012年第1期76-82,共7页
It is important to quantify mass variations in the Antarctic ice sheet hybrid filtering scheme employing a combination of the decorrelated to study the global sea-level rise and climate change. A filter P3M6 and 300 k... It is important to quantify mass variations in the Antarctic ice sheet hybrid filtering scheme employing a combination of the decorrelated to study the global sea-level rise and climate change. A filter P3M6 and 300 km Fan filter was used, and the sur- face mass variations over the Antarctic are recovered from GRACE CSR RL04 monthly gravity field models from August 2002 to June 2010. After deduction of leakage errors using the GLDAS hydrological model and postglacial rebound effects using the glacial isostatic adjustment model IJ05, the variations in the ice sheet mass are obtained. The results reveal that the rate of melting of the Antarctic ice sheet is 80.0 Gt/a and increasing and contributes 0.22 mm/a to the global sea-level rise; the mass loss rate is 78.3 Gt/a in the West Antarctic and 1.6 Gt/a in the East Antarctic. The average mass loss rate increases from 39.3 Gt/a for the period 2002-2005 to 104.2 Gt/a for the period 2006-2010, and its corresponding contribution to the global sea-level rise increases from 0.11 to 0.29 mm/a, which indicates accelerated ice mass loss over the Antarctic since 2006. Moreover, the mass accumulation rates for Enderby Land and Wilkes Land along the coast of East Antarctica decrease for the period 2006-2008 but increase evidently after 2009. 展开更多
关键词 GRACE temporal gravity field Antarctic ice sheet mass variation
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Forming Limit Stress Diagram Prediction of Aluminum Alloy 5052 Based on GTN Model Parameters Determined by In Situ Tensile Test 被引量:20
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作者 HE Min LI Fuguo WANG Zhigang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2011年第3期378-386,共9页
The conventional forming limit diagram (FLD) is described as a plot of major strain versus minor strain. However, FLD is dependent on forming history and strain path. In the present study, a forming limit stress-bas... The conventional forming limit diagram (FLD) is described as a plot of major strain versus minor strain. However, FLD is dependent on forming history and strain path. In the present study, a forming limit stress-based diagram (FLSD) has been adopted to predict the fracture limit of aluminum alloy (AA) 5052-O1 sheet. Nakazima test is simulated by plastic constitutive formula derived from the modified Gurson-Tvergaard-Needleman (GTN) model. An in situ tensile test with scanning electron microscope (SEM) is proposed to determine the parameters in GTN model. The damage evolution is observed and recorded, and the parameters of GTN model are identified through counting void fraction at three damage stages of AA5052-O 1. According to the experimental results, the original void volume fraction, the volume fraction of potential nucleated voids, the critical void volume fraction, the void volume fraction at the final failure of material are assigned as 0.002 918, 0.024 9, 0.030 103, 0.048 54, respectively. The stress and strain are obtained at the last loading step before crack. FLSD and FLD of AA5052-O 1 are plotted. Compared with the experimental Nakazima test and uniaxial tensile test, the predicted results show a good agreement. The parameters determined by in situ tensile test can be applied to the research of the forming limit for ductile metals. 展开更多
关键词 forming limit stress diagram GTN model in situ tensile test void damage aluminum alloy 5052-O1 sheet metal forming
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铝合金中厚板的生产、市场与应用 被引量:20
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作者 王祝堂 《轻合金加工技术》 CAS 北大核心 2005年第1期1-20,共20页
对中国铝合金中厚板的生产、市场与应用作了全面系统的介绍,还简介了美国铝厚板的产量与厚薄板比例,以及世界主要国家厚板的价格,厚板的主要应用领域,厚板铝合金的成分、热处理规范与轧制率系统。对中国中厚板2005年至2016年的需求作了... 对中国铝合金中厚板的生产、市场与应用作了全面系统的介绍,还简介了美国铝厚板的产量与厚薄板比例,以及世界主要国家厚板的价格,厚板的主要应用领域,厚板铝合金的成分、热处理规范与轧制率系统。对中国中厚板2005年至2016年的需求作了预测,2005年的需求量为106kt,2010年的需求量为210kt,2015年的为380kt。中国目前是一个中厚铝合金板净进口国。中国需要建设铝合金中厚板生产线,热粗轧最好是4000mm级的,其他装备与精整设备应配套齐全,这种生产线的建设宜早不宜晚。美国厚板(大于6.25mm)产量占板带材(不含铝箔毛料)总产量的4%,中国中厚板(大于4.5mm)产量约占板带材总产量的5%。 展开更多
关键词 铝合金 厚板 薄板 市场
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汽车用低合金钢的现状与发展 被引量:14
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作者 张凤泉 陈贵江 +4 位作者 康永林 杨雄飞 刘本仁 刘文仲 欧阳金明 《特殊钢》 北大核心 2003年第4期1-4,共4页
分析了我国汽车用低合金钢材 ,包括汽车用低合金、微合金热轧钢板、冷轧钢板、弹簧钢、渗碳钢、易切削钢等的成分与性能及应用状况 ,探讨了今后汽车用低合金。
关键词 汽车 低合金钢 微合金化 钢板 弹簧钢 渗碳钢 易切削钢
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板料激光成形及其研究进展 被引量:13
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作者 刘韧 季忠 +1 位作者 张鹏 贾玉玺 《锻压装备与制造技术》 北大核心 2004年第3期17-21,共5页
从理论研究、数值模拟、实验研究等方面,介绍了板料激光成形技术的发展历史、研究现状及发展方向。指出激光成形技术的研究方法主要有实验方法和数值方法,但目前仍在成形多种材料、变革成形工艺等较低层次上进行徘徊,但其最终目的应体... 从理论研究、数值模拟、实验研究等方面,介绍了板料激光成形技术的发展历史、研究现状及发展方向。指出激光成形技术的研究方法主要有实验方法和数值方法,但目前仍在成形多种材料、变革成形工艺等较低层次上进行徘徊,但其最终目的应体现在研究激光照射时材料在热应力作用下产生塑性变形的可控性上。激光成形技术的最大难点在于要制作出满足预定形状及尺寸要求的工件;同时,激光成形是一种累积成形,一次激光扫描所产生的变形量很小,往往经过数次激光扫描的累积才能达到所需的变形量,因而,研究出一套效率高、耗能少、工艺稳定的最佳工艺参数组合很有意义,这也就是本领域的难点之二。 展开更多
关键词 机械制造 板材加工 激光成形 数值模拟 激光扫描 工艺参数
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用物理发泡剂制备韧性泡沫硅橡胶 被引量:16
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作者 胡义 姚国萍 《有机硅材料》 CAS 2000年第1期11-14,共4页
用物理发泡剂制备了具有特殊性能要求的韧性泡沫硅橡胶, 重点介绍了原材料预处理、成型技术及加工工艺参数等。应用本工艺可对复杂曲面、平面薄片( 厚度≤0-3 m m) 、不同密度、不同厚度、不同孔隙率及不同力学性能要求的泡沫... 用物理发泡剂制备了具有特殊性能要求的韧性泡沫硅橡胶, 重点介绍了原材料预处理、成型技术及加工工艺参数等。应用本工艺可对复杂曲面、平面薄片( 厚度≤0-3 m m) 、不同密度、不同厚度、不同孔隙率及不同力学性能要求的泡沫硅橡胶实现一次性成型, 材料综合物性指标优于化学发泡, 具有一定的实用价值。 展开更多
关键词 物理发泡 硅橡胶 泡沫橡胶 发泡剂 韧性
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Hot Granules Medium Pressure Forming Process of AA7075 Conical Parts 被引量:16
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作者 DONG Guojiang ZHAO Changcai +1 位作者 PENG Yaxin LI Ying 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期580-591,共12页
High strength aluminum alloy plate has a low elongation at room temperature, which leads to the forming of its components need a high temperature. Liquid or gas is used as the pressure-transfer medium in the existing ... High strength aluminum alloy plate has a low elongation at room temperature, which leads to the forming of its components need a high temperature. Liquid or gas is used as the pressure-transfer medium in the existing flexible mould forming process, the heat resistance of the medium and pressurizing device makes the application of aluminum alloy plate thermoforming restricted. To solve this problem, the existing medium is replaced by the heat-resisting solid granules and the general pressure equipments are applied. Based on the pressure-transfer performance test of the solid granules medium, the feasibility that the assumption of the extended Drucker-Prager linear model can be used in the finite element analysis is proved. The constitutive equation, the yield function and the theoretical forming limit diagram(FLD) of AA7075 sheet are established. Through the finite element numerical simulation of hot granules medium pressure forming(HGMF) process, not only the influence laws of the process parameters, such as forming temperature, the blank-holder gap and the diameter of the slab, on sheet metal forming performance are discussed, but also the broken area of the forming process is analyzed and predicted, which are coincided with the technological test. The conical part whose half cone angle is 15° and relative height H/d0 is 0.57, is formed in one process at 250℃. The HGMF process solves the problems of loading and seal in the existing flexible mould forming process and provides a novel technology for thermoforming of light alloy plate, such as magnesium alloy, aluminium alloy and titanium alloy. 展开更多
关键词 granules medium aluminum alloy sheet DRAWING hot forming forming limit diagram
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FAST ACCURATE PREDICTION OF BLANK SHAPE IN SHEET METAL FORMING 被引量:14
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作者 LiuYuqi LiZhigang YahYakun 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第1期58-64,共7页
By using the Finite Element Inverse Approach based on the Hill quadratic anisotrop-ically yield criterion and the quadrilateral element, a fast analyzing software-FASTAMP for the sheet metal forming is developed. The ... By using the Finite Element Inverse Approach based on the Hill quadratic anisotrop-ically yield criterion and the quadrilateral element, a fast analyzing software-FASTAMP for the sheet metal forming is developed. The blank shapes of three typical stampings are simulated and compared with numerical results given by the AUTOFORM software and experimental results, respectively. The comparison shows that the FASTAMP can predict blank shape and strain distribution of the stamping more precisely and quickly than those given by the traditional methods and the AUTOFORM. 展开更多
关键词 sheet metal forming Finite Element Inverse Approach blank shape FASTAMP software
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Effect of Long-Term Fertilization on Soil Productivity and Nitrate Accumulation in Gansu Oasis 被引量:15
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作者 YANG Sheng-mao LI Feng-min +4 位作者 SUO Dong-rang GUO Tian-wen WANG Jian-guo SONG Bing-ling JIN Shao-ling 《Agricultural Sciences in China》 CAS CSCD 2006年第1期57-67,共11页
A long-term (1982-2001) field experiment was conducted in a calcareous soil under wheat (Triticum aestivum L.)-wheat (Triticum aestivum L.)-maize (Zea mays L.) rotation system at Zhangye, Gansu Province, China... A long-term (1982-2001) field experiment was conducted in a calcareous soil under wheat (Triticum aestivum L.)-wheat (Triticum aestivum L.)-maize (Zea mays L.) rotation system at Zhangye, Gansu Province, China to determine the effects of long-term fertilization on crop yield, nutrients interactions, content and accumulation of nitrate-N in soil profiles. Twenty- four plots in a split-plot factorial with a combination of eight treatments (from nitrogen (N), phosphorus (P), potassium (K) and farmyard manure (M) applications) and 3 replications were selected. Main treatments were M and without M, and the sub-treatments were no-fertilizer (CK), N, NP and NPK. When P and K fertilizers were part of treatments, their ratio to N was 1N:0.22P:0.42K. All M, P and K fertilizers were applied as the basal dressing. The grain yield was harvested each experimental period and straw yield for the period from 1988 to 1997. After crop harvest in 2000, the soil was sampled from the 0-20, 20-60, 60-100, 100-140 and 140-180 cm depths to determine NO3^--N content. Maize yield of CK in 2000 was only 28.2% of that in 1984, and wheat in 2001 was 25.7% of that observed in 1982. Average impact of fertilizers on grain yield decreased in the order of N 〉 M 〉 P 〉 K. Yield response to N and P fertilizers increased with progress of the experiment. The impact of K fertilizer showed no increase in grain yield during the initial 6 years (1982-1987), moderate increase in the next 5 years (1988-1992), and considerable increase in the last 9 years (1993-2001). The straw yield trend was similar to grain yield. Accumulation and distribution of NO3^--N in soil was significantly affected by annual fertilizations. Mineral fertilizers (NP and NPK) led to NO3^- -N accumulation in most subsoil layers, with major impact in the 20-140 cm depth. The combination of mineral fertilizers and farmyard manure (MNP and MNPK) reduced soil NO3^--N accumulation in comparison to mineral fertilizers, It c 展开更多
关键词 long-term fertilization accumulation of nitrate-N crop yields nutrients interactions farmyard manure Nbalance sheet Zhangye Oasis
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元素粉末冷轧成形及反应合成制备Ti-Al合金板材 被引量:11
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作者 江垚 贺跃辉 +2 位作者 汤义武 李智 黄伯云 《中国有色金属学报》 EI CAS CSCD 北大核心 2004年第9期1501-1507,共7页
以Ti、Al元素粉末为原料,在粉末轧机上无包套冷轧成尺寸为500mm×230mm×1.5mm的板坯,其相对密度达85.9%。研究了不同工艺参数对Ti、Al元素粉末轧制板材的影响。取小样在不同温度下进行真空无压烧结,研究了板坯的真空烧结行为... 以Ti、Al元素粉末为原料,在粉末轧机上无包套冷轧成尺寸为500mm×230mm×1.5mm的板坯,其相对密度达85.9%。研究了不同工艺参数对Ti、Al元素粉末轧制板材的影响。取小样在不同温度下进行真空无压烧结,研究了板坯的真空烧结行为。结果表明:Ti、Al元素粉末冷轧过程要求适中的粉末流动性、低的轧制速度以及一定大小且较稳定的轧制压力。真空烧结后,Ti Al合金由Ti Al和Ti3Al两相组成,Ti3Al相含量随烧结温度升高而增加。烧结坯孔隙度大幅度增加,增加量为21%32%。原板坯中的孔隙及偏扩散是造成烧结坯孔隙的主要原因。低压(<10kPa)真空烧结过程中,外压仅有效作用于短暂的液相阶段,粉末粒度越粗,烧结温度越高,烧结坯孔隙度受这种低压强的影响程度越大。 展开更多
关键词 Ti—Al合金 元素粉末 轧制 真空烧结 板材
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