共查询到20条相似文献,搜索用时 62 毫秒
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采用光学显微镜(OM)、维氏硬度计、涡流电导仪、万能试验机等研究了3A21合金经不同温度(520~640℃)均匀化处理后的组织与性能。结果表明,最佳均匀化制度为620℃×8 h,经该工艺处理后合金未发现过烧组织,晶界细小,呈断续分布,晶内偏析情况得到缓解,有利于后续挤压加工。该工艺下合金均匀化态的硬度为40 HV5,电导率35.8%IACS。经最佳均匀化工艺(620℃×8 h)处理后挤压3A21合金型材的抗拉强度124 MPa,屈服强度77 MPa,伸长率48%,硬度37 HV5,电导率48.7%IACS。 相似文献
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本文研究了3A21铝合金管材生产工艺,通过对3A21铝合金的原料成分、挤压工艺和热处理条件的分析,开发了优质高塑耐蚀3A13铝合金挤压管材生产工艺。最终确定了3A21铝合金成分,铸棒的均匀化处理制度,管材的挤压工艺参数,管材的退火处理制度。经特定成分挤压后得到的3A21铝合金管材,通过430℃×1. 5 h退火处理后,伸长率可达到46%,同时抗腐蚀性在PH值4. 0的酸性条件下可保持46 h,没有肉眼可见的腐蚀点,满足客户需求。 相似文献
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对3A21铝合金铸轧坯料生产散热片用带材的工艺进行了研究,制定了带材的成品退火制度.找出了散热片在钎焊过程中发生变形不均及焊合不良的原因.通过跟踪试验,在真空钎焊炉内加入镁屑,解决了质量问题,提高了散热片的钎焊成品率. 相似文献
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中间合金中第二相粒子TiC和TiAl3对纯铝的细化作用 总被引:2,自引:1,他引:1
研究Al-TiC和Al-TiAl3中间合金中第二相粒子TiC和TiAl3 对纯铝晶粒的细化作用.结果表明:当TiC和TiAl3单独作为α(Al)的形核相时,两者的形核能力均较差,但TiC粒子的形核和抗细化衰退能力优于TiAl3粒子的;当第二相粒子TiC和TiAl3共同作为α(Al)的形核相,且加入量适当时,表现出较强的形核能力和抗晶粒细化的衰退能力,细化效果较显著;配成的7组晶粒细化剂中,当细化剂中Ti和C摩尔比为1.8-1时,晶粒细化效果最好;这是由于TiAl3在铝熔体中分解释放出Ti原子并向TiC粒子周围偏聚,形成的TiC/铝熔体界面富Ti过渡区促进了TiC粒子在铝熔体中的均匀分布,提高了其形核能力. 相似文献
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锻造高铌双态TiAl合金的冷轧工艺及组织力学性能研究 总被引:1,自引:0,他引:1
采用道次小压下量的工艺对高铌双态TiAl 锻造合金进行精确控制的冷轧实验.结果表明:冷轧后整个试样变形均匀,总变形量在没有中间退火的情况下最大可超过20%.合金变形后的组织仍然为双态组织,γ组织沿轧制方向拉伸变长,片层组织也由原来的无序分布变为与轧向呈一定角度分布.退火实验表明,不同的变形量、退火温度和退火时间对冷轧高铌钛铝合金的力学性能和显微组织均有明显的影响,因而不同的压下量,其中间退火工艺是不同的. 相似文献
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用铝合金管材制作散热器须进行扩口加工,其间往往会因为管材端部出现裂口而报废。研究了扩口加工时管材的变形特点,分析了产生裂口的主要原因,提出了消除它的主要措施。 相似文献
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研究了铁模铸造的3A21合金带材生产工艺,讨论了消除冷轧带材因成品退火产生粗大晶粒措施的效果,确定再结晶温度。按所研究的工艺,生产出力学性能良好,深冲性良好无制耳的产品。 相似文献
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3A21铝合金板带材再结晶退火组织性能的研究 总被引:3,自引:0,他引:3
试验和讨论了3A21铝合金连续铸轧卷的成分,冷轧变形程度、退火温度与保温时间对该合金板带材再结晶退火后组织与性能的影响规律,提出了一些可获得良好晶粒度和机械性能的控制方法。 相似文献
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An investigation on the hot extrusion process of magnesium alloy sheet 总被引:11,自引:0,他引:11
This study investigates the hot extrusion of magnesium alloy sheets at various temperatures, material, speed and lubricant. A multi-speed method is applied to extrude a magnesium alloy sheet at a high extrusion ratio. The experimental results are analyzed to optimize the processing conditions, increase the tensile strength and reduce the extrusion load on the magnesium alloy thin sheet. Nowadays, most magnesium alloy products are manufactured by industrial die casting. Hot extrusion is seldom used to finish magnesium products because the extrusion speed, temperature and extrusion load significantly effect the properties of the product. In this study, the Taguchi experimental method with the orthogonal array is applied. ANOVA is used to investigate how parameters affect the extrusion process. All possible mechanical properties of the product are analyzed to obtain the optimal process parameters. In addition, magnesium alloys with different compositions are experimentally tested to determine the mechanical properties of the extruded product and obtain the relationship between the process parameters and the properties of the material. 相似文献
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镁合金板材挤压工艺参数较难控制,挤压温度与挤压速度的合理匹配是挤压成功与否的关键.以宽度700 mm、厚度4 mm的AZ31B镁合金薄板为研究对象,基于Forge软件和Normalized Crockroft&Latham断裂准则对其挤压过程进行了模拟.结果表明,挤压初期,铸锭上、下部金属逐渐向心部流动,左、右两侧金属流动与挤压速度保持同向;中、后期,±45.方向金属发生分离,一部分与上、下部金属合流后继续向心部流动,另一部分与左、右侧金属合流后向薄板宽度方向扩展.随挤压行程增加,成形薄板加长,局部高温区域由薄板两侧向中间部分转移;初始挤压温度400℃时,若挤压速度超过1 mm·s-1,薄板局部高温区域温度较高,成形质量和使用性能不易保证.采用380 ~ 400℃的初始挤压温度,大约0.2 mm·s-1的挤压速度,既可以显著降低设备成本,又利于保证薄板使用性能. 相似文献
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Effect of blank holder force control in deep-drawing process of magnesium alloy sheet 总被引:12,自引:0,他引:12
Shoichiro Yoshihara Ken-ichi Manabe Hisashi Nishimura 《Journal of Materials Processing Technology》2005,170(3):579-585
A circular cup deep-drawing process was investigated using a magnesium alloy material, which is the lightest practical material for use in manufacturing structural components. An improvement in the limiting drawing ratio (LDR) at 300 °C was observed, by controlling a variable blank holder force (BHF) during the process, in comparison with the constant BHF conditions. The reason for the improvement of the LDR is that the magnesium alloy material has a low F-value, which was obtained from tensile tests when it was warmed to the elevated temperature. When the experimental conditions are not appropriate, such as when BHF is high, the experimentally drawn cup fractured at the wall part (β-rupture). The LDR of the magnesium alloy sheet was improved using the BHF control technique and verified using a finite element method (FEM) simulation. It is confirmed that the FEM simulations behaved in a similar manner to the experiments, with β-rupture being observed during the fracture at the wall part. 相似文献
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从铝钎焊机及具体工艺操作方面进行阐述,解决了LF21防锈铝用氧-乙烯火焰作为热源进行钎焊的工艺问题。 相似文献
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A ductile fracture criterion is introduced into numerical simulation to predict viscous pressure forming limit of the automotive body aluminum alloy 6k2 l-T4. The material constant in the ductile fracture criterion is determined by the combination of the viscous pressure bulging (VPB) test with numerical simulation. VPB tests of the aluminum alloy sheet are carried out by using various elliptical dies with different ratios of major axis to minor axis(β), and the bugling processes are simulated by the aid of the finite element method software LS-DYNA3D. On the basis of the stress and strain calculated from numerical simulations, the forming limits of bulging specimens obtained are predicted by the ductile fracture criterion, and compared with experimental results. The fracture initiation site and the minimal thickness predicted by the ductile fracture criterion are in good agreement with the experimental results. 相似文献