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Microstructure and high temperature tribological behavior of laser cladding Ni60A alloys coatings on 45 steel substrate 被引量:21
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作者 张健 胡玉 +2 位作者 谭小军 郭亮 张庆茂 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1525-1532,共8页
The crack-free Ni60 A coating was fabricated on 45 steel substrate by laser cladding and the microstructure including solidification characteristics, phases constitution and phase distribution was systematically inves... The crack-free Ni60 A coating was fabricated on 45 steel substrate by laser cladding and the microstructure including solidification characteristics, phases constitution and phase distribution was systematically investigated. The high temperature friction and wear behavior of the cladding coating and substrate sliding against GCr15 ball under different loads was systematically evaluated. It was found that the coating has homogenous and fine microstructure consisting of γ(Ni) solid solution, a considerable amount of network Ni-Ni3 B eutectics, m^23C6 with the floret-shape structure and Cr B with the dark spot-shape structure uniformly distributing in interdendritic eutectics. The microhardness of the coating is about 2.6 times as much as that of the substrate. The coating produces higher friction values than the substrate under the same load condition, but the friction process on the coating keeps relatively stable. Wear rates of the coating are about 1/6.2 of that of the substrate under the higher load(300 g). Wear mechanism of the substrate includes adhesion wear, abrasive wear, severe plastic deformation and oxidation wear, while that of the coating is merely a combination of mild abrasive wear and moderate oxidation wear. 展开更多
关键词 laser cladding ni60A alloy 45 steel MICROSTRuCTuRE tribological behavior
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Electrochemical hydrogen storage characteristics of nanocrystalline and amorphous Mg_2Ni-type alloys prepared by melt-spinning 被引量:4
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作者 张羊换 吕科 +3 位作者 赵栋梁 郭世海 祁焱 王新林 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期502-511,共10页
The nanocrystalline and amorphous Mg2Ni-type alloys with nominal compositions of Mg2Ni1-xMnx (x=0, 0.1, 0.2, 0.3, 0.4) were synthesized by melt-spinning technique. The spun alloy ribbons with a continuous length, a ... The nanocrystalline and amorphous Mg2Ni-type alloys with nominal compositions of Mg2Ni1-xMnx (x=0, 0.1, 0.2, 0.3, 0.4) were synthesized by melt-spinning technique. The spun alloy ribbons with a continuous length, a thickness of about 30 μm and a width of about 25 mm are obtained. The structures of the as-spun alloy ribbons were characterized by XRD and HRTEM. The electrochemical hydrogen storage characteristics of the as-spun alloy ribbons were measured by an automatic galvanostatic system. The electrochemical impedance spectrums (EIS) were plotted by an electrochemical workstation. The hydrogen diffusion coefficients (D) in the alloys were calculated by virtue of potential-step measurement. The results show that all the as-spun (x=0) alloys hold a typical nanocrystalline structure, whereas the as-spun (x=0.4) alloy displays a nanocrystalline and amorphous structure, confirming that the substitution of Mn for Ni facilitates the glass formation in the Mg2Ni-type alloy. The substitution of Mn for Ni significantly improves the electrochemical hydrogen storage performances of the alloys, involving the discharge capacity and the electrochemical cycle stability. With an increase in the amount of Mn substitution from 0 to 0.4, the discharge capacity of the as-spun (20 m/s) alloy increases from 96.5 to 265.3 mA·h/g, and its capacity retaining rate (S20) at the 20th cycle increases from 31.3% to 70.2%. Furthermore, the high rate dischargeability (HRD), electrochemical impedance spectrum and potential-step measurements all indicate that the electrochemical kinetics of the alloy electrodes first increases then decreases with raising the amount of Mn substitution. 展开更多
关键词 Mg2ni-type alloy electrochemical hydrogen storage MELT-SPINniNG substituting ni with Mn
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First-principles study of stacking fault energies in Ni_3Al intermetallic alloys 被引量:5
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作者 温玉锋 孙坚 黄健 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期661-664,共4页
The first-principles method based on the projector augmented wave method within the generalized gradient approximation was employed to calculate the superlattice intrinsic stacking fault(SISF) and complex stacking f... The first-principles method based on the projector augmented wave method within the generalized gradient approximation was employed to calculate the superlattice intrinsic stacking fault(SISF) and complex stacking fault(CSF) energies of the binary Ni3Al alloys with different Al contents and the ternary Ni3Al intermetallic alloys with addition of alloying elements,such as Pd,Pt,Ti,Mo,Ta,W and Re.The results show that the energies of SISF and CSF increase significantly with increase of Al contents in Ni3Al.Addition of Pd and Pt occupying the Ni sublattices does not change the SISF and CSF energies of Ni3Al markedly in comparison with the Ni-23.75Al alloy.While addition of alloying elements,such as Ti,Mo,Ta,W and Re,occupying the Al sublattices dramatically increases the SISF and CSF energies of Ni3Al.The results suggest that the energies of SISF and CSF are dependent both on the Al contents and on the site occupancy of the ternary alloying element in Ni3Al intermetallic alloys. 展开更多
关键词 ni3AL superlattice intrinsic stacking fault complex stacking fault alloying element FIRST-PRINCIPLES
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Thermodynamic analysis on synthesis of fibrous Ni-Co alloys precursor and Ni/Co ratio control 被引量:3
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作者 湛菁 贺跃辉 +1 位作者 周涤非 张传福 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1141-1148,共8页
According to the principles of simultaneous equilibrium and mass equilibrium, a series of thermodynamic equilibrium equations in Ni(II)-Co(II)-C2O4^2--NH3-NH4^+-H2O system at ambient temperature were deduced. The... According to the principles of simultaneous equilibrium and mass equilibrium, a series of thermodynamic equilibrium equations in Ni(II)-Co(II)-C2O4^2--NH3-NH4^+-H2O system at ambient temperature were deduced. The diagrams of logarithm ion concentrations versus pH values at different solution compositions were drawn. The results show that Ni^2+ and Co^2+ can completely precipitate at pH less than 5.0 and the predefined Ni/Co ratios can be well kept in the precursor. The precursor morphology is granular aggregation. However, rod aggregation precursor is obtained in the pH range of 5.0-8.0, and fibre-shape precursor is got at pH value higher than 8.0. The Ni/Co ratios in the above two precursors are not reproduced as that in the feed due to the formhtion of multi-coordinated Ni(NH3)n^2+ and Co(NH3)n^2+ (n=1-6). Modification of precipitation medium is favorable for the precursors to keep the predefined Ni/Co ratios of the feed in the pH range of 2.0-8.6. Meanwhile, the precursors with fibrous morphology can be obtained. 展开更多
关键词 thermodynamic analysis nickel-cobalt alloy nickel-cobalt oxalate precursor predefined ni/Co ratio fibre-shape
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Hot corrosion behavior of Ni–16Cr–xAl based alloys in mixture of Na_2SO_4-NaCl at 600 ℃ 被引量:4
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作者 李维杰 刘咏 +2 位作者 王岩 韩朝 汤慧萍 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2617-2625,共9页
The hot corrosion behaviors of Ni–16Cr–xAl(x=4.5%, 6.8%, 9.0%, mass fraction) based alloys in Na2SO4–25% NaCl molten salts at 600 °C were investigated. The effects of pre-oxidation and Al content on the resi... The hot corrosion behaviors of Ni–16Cr–xAl(x=4.5%, 6.8%, 9.0%, mass fraction) based alloys in Na2SO4–25% NaCl molten salts at 600 °C were investigated. The effects of pre-oxidation and Al content on the resistance to hot corrosion were examined. The hot corrosion resistance of Ni–16Cr–xAl based alloy with Al addition from 4.5% to 9.0% increases with increasing Al content. The alloy with Al content of 9.0% shows the highest hot corrosion resistance among the examined alloys because more β–NiAl phases are obtained to sustain the Al2O3 scale repaired during hot corrosion. Pre-oxidized specimens have a superior hot corrosion resistance compared with the as-cast specimens, due to a protective oxide scale formed after pre-treatment. 展开更多
关键词 ni–16Cr–xAl based alloys PRE-OXIDATION Na2SO4–25% NaCl mixed salt hot-corrosion mechanism
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固溶处理及工艺路径对Cu-Ni-Si-Co合金板材性能的影响
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作者 梁海成 惠文芃 +3 位作者 陈帅峰 李应焕 宋鸿武 张士宏 《精密成形工程》 北大核心 2024年第7期144-152,共9页
目的系统探究了不同固溶温度及不同冷轧时效工艺对C7035合金力学性能与导电性能的影响规律。方法针对C7035合金进行了不同温度的固溶处理,并进行了冷轧以及不同温度的时效处理。对比一次时效的力学性能与电学性能差异性,并优化工艺路径... 目的系统探究了不同固溶温度及不同冷轧时效工艺对C7035合金力学性能与导电性能的影响规律。方法针对C7035合金进行了不同温度的固溶处理,并进行了冷轧以及不同温度的时效处理。对比一次时效的力学性能与电学性能差异性,并优化工艺路径。选择性能较为优异的样品观察其微观组织以及析出相。结果提高固溶温度可显著提升一次冷轧-时效合金的硬度、强度以及导电性,其中性能较为优异的工艺参数为960℃固溶1 h、冷轧90%、450℃时效3 h,对应板材的维氏硬度、抗拉强度及导电率分别为241.2HV0.1、777 MPa、48.6%IACS。工艺优化后,较优异的工艺参数为960℃固溶1 h、冷轧90%、450℃预时效0.5 h、冷轧50%、450℃时效2 h,对应板材的维氏硬度、抗拉强度及导电率分别为252.8HV0.1、787 MPa、41.2%IACS。结论固溶温度越高,溶质原子溶入基体的数量越多,固溶后能观察到的第二相越少。960℃固溶后一次冷轧-时效的强度较高,与880℃固溶后一次冷轧-时效后相比,强度提高了约100 MPa,二次冷轧时效后,强度有进一步的提升。 展开更多
关键词 Cu-ni-Si-Co合金 固溶处理 工艺路径 抗拉强度 导电率
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Modeling of Ni_4Ti_3 precipitation during stress-free and stress-assisted aging of bi-crystalline NiTi shape memory alloys
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作者 柯常波 曹姗姗 +1 位作者 马骁 张新平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2578-2585,共8页
The phase field method was applied to study the microstructure evolution of Ni4Ti3 precipitates during stress-free and stress-assisted aging of bi-crystalline NiTi shape memory alloys (SAMs) with two different initi... The phase field method was applied to study the microstructure evolution of Ni4Ti3 precipitates during stress-free and stress-assisted aging of bi-crystalline NiTi shape memory alloys (SAMs) with two different initial Ni-contents of 51.5% and 52.5% (mole fraction), respectively. The simulation results show that, during stress-free aging of the NiTi alloy with a low supersaturation of Ni (i.e., Ti-51.5%Ni), the Ni4Ti3 precipitates exhibit a heterogeneous distribution with a high number density of particles at the grain boundary, leaving most of the grain interiors free of precipitates; while for the NiTi alloy with a high supersaturation of Ni (i.e., Ti-52.5%Ni), the Ni4Ti3 precipitates show a homogeneous distribution across the entire simulation system. The stress-assisted aging can give rise to homogeneous distribution of the precipitates, regardless of the initial Ni-content; however, the distribution of variant type within the two grains is heterogeneous. 展开更多
关键词 niTi shape memory alloy ni4Ti3 precipitate low-angle grain boundary martensitic transformation phase field simulation
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Application and Present Research Status of Electrodeposited Ni-W Alloys 被引量:5
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作者 李晓闲 张雪辉 刘坚锋 《上海有色金属》 CAS 2010年第2期88-93,共6页
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高性能Cu-Ni-Si系合金研究现状及发展趋势 被引量:2
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作者 刘军 曹祎程 +3 位作者 米绪军 解浩峰 米振莉 彭丽军 《铜业工程》 CAS 2024年第3期152-162,共11页
先进铜基材料具有广阔的市场及良好的发展前景。相比于Cu-Be, Cu-Fe-P, Cu-Cr等合金而言,Cu-Ni-Si系合金具有高强度、较高的导电率、良好的抗高温软化、抗应力松弛性能及低廉的价格等优点,广泛应用于机械制造、航空航天、交通运输、电... 先进铜基材料具有广阔的市场及良好的发展前景。相比于Cu-Be, Cu-Fe-P, Cu-Cr等合金而言,Cu-Ni-Si系合金具有高强度、较高的导电率、良好的抗高温软化、抗应力松弛性能及低廉的价格等优点,广泛应用于机械制造、航空航天、交通运输、电子和电气工程等工业领域。本文首先介绍了Cu-Ni-Si系合金的发展现状,并从产品性能及产业化方面论述了国内外存在的差异。该合金发展趋势主要是朝着先进高强高导弹性铜合金方向发展,核心挑战是在提升强度的同时保持甚至提高导电性能,并且由于服役环境的复杂化及服役时间的延长,对于材料服役性能的可靠稳定性也提出了更为严苛的要求。最后从成分设计、加工及形变热处理工艺、时效析出行为、服役性能等方面综述了CuNi-Si系合金的研究现状,并针对目前该材料存在的不足,展望了高强度高导电铜合金的未来发展趋势。 展开更多
关键词 Cu-ni-Si系合金 铜合金 高强高导 引线框架 发展趋势
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溶胶-凝胶法制备高分散Ni-Cu/SiO_(2)促进间甲酚直接脱氧制甲苯 被引量:1
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作者 王颖杰 祝新利 《化工进展》 EI CAS CSCD 北大核心 2024年第7期3824-3833,共10页
在木质素生物质衍生的酚类化合物加氢脱氧生产芳烃中,Ni基催化剂兼具经济性与活性,然而,在温和条件下会受到C—C氢解的影响。在此,采用溶胶-凝胶法制备了高分散的Ni/SiO_(2)、Cu/SiO_(2)和不同Cu含量的双金属Ni-Cu催化剂,并在350℃和常... 在木质素生物质衍生的酚类化合物加氢脱氧生产芳烃中,Ni基催化剂兼具经济性与活性,然而,在温和条件下会受到C—C氢解的影响。在此,采用溶胶-凝胶法制备了高分散的Ni/SiO_(2)、Cu/SiO_(2)和不同Cu含量的双金属Ni-Cu催化剂,并在350℃和常压条件下对其进行间甲酚加氢脱氧性能测试。尽管Ni粒径约为2nm的单金属Ni/SiO_(2)表现出高的活性和甲苯选择性,但C—C氢解生成甲烷和苯的反应仍然显著。对于双金属Ni-Cu催化剂,Ni和Cu相互作用并在还原后形成Ni-Cu合金。在最佳的双金属催化剂(Cu/Ni摩尔比约为3)上,甲苯在所有转化水平上都是主要产物。当间甲酚转化率为97.2%时,甲苯和芳烃的收率分别达到85.0%和91.6%。本征反应速率和活化能分析表明,Cu的引入通过抑制竞争性的C—C氢解反应,促进了直接脱氧生成甲苯。 展开更多
关键词 催化 生物质 再生能源 间甲酚 加氢脱氧 ni-Cu合金
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形变热处理对Cu-Ni-Si合金组织性能的影响
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作者 单运启 张彦敏 +6 位作者 张朝民 刘爱奎 冯江 赵世恒 皇保欢 宋克兴 周延军 《材料热处理学报》 CAS CSCD 北大核心 2024年第1期95-102,共8页
借助扫描电镜、电子万能试验机、维氏硬度计和数字涡流金属电导仪等研究了冷轧变形量和时效对Cu-Ni-Si合金组织与性能的影响。结果表明:冷轧态合金变形量越大,显微组织中晶粒沿着轧制的方向被拉得越长和越扁。当时效温度或时效时间增加... 借助扫描电镜、电子万能试验机、维氏硬度计和数字涡流金属电导仪等研究了冷轧变形量和时效对Cu-Ni-Si合金组织与性能的影响。结果表明:冷轧态合金变形量越大,显微组织中晶粒沿着轧制的方向被拉得越长和越扁。当时效温度或时效时间增加到一定程度时,冷变形晶粒发生了回复再结晶,时效时间继续延长再结晶晶粒逐渐长大。冷轧态合金主要以脆性断裂为主,时效态合金以韧性断裂为主。当冷轧变形量为80.0%及经500℃×1 h时效后合金的综合性能最佳,电导率为46.37%IACS,显微硬度为236.14 HV0.1,抗拉强度为638.24 MPa,屈服强度为581.55 MPa,伸长率为5.77%。 展开更多
关键词 Cu-ni-SI合金 形变热处理 显微组织 力学性能
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Mn含量对铸态Cu-Ni-Cr合金组织和性能的影响
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作者 朱莹莹 国秀花 +3 位作者 李韶林 宋克兴 王强松 孙文明 《材料热处理学报》 CAS CSCD 北大核心 2024年第1期103-112,共10页
采用大气熔炼制备了Cu-Ni-Cr-xMn(x=0、1、3、5、7和9 mass%)合金,采用光学显微镜、扫描电镜、X射线衍射仪和电子万能试验机等研究了Mn含量对铸态Cu-Ni-Cr-xMn合金显微组织和性能的影响。结果表明:铸态Cu-Ni-Cr-xMn合金的组织由富Cu相(... 采用大气熔炼制备了Cu-Ni-Cr-xMn(x=0、1、3、5、7和9 mass%)合金,采用光学显微镜、扫描电镜、X射线衍射仪和电子万能试验机等研究了Mn含量对铸态Cu-Ni-Cr-xMn合金显微组织和性能的影响。结果表明:铸态Cu-Ni-Cr-xMn合金的组织由富Cu相(γ1)、富Ni相(γ2)和富Cr相组成,Mn的添加显著改变了Cu-Ni-Cr-xMn合金组织中第二相的偏聚形式。Mn的加入使Cu-Ni-Cr-xMn合金组织中的Cr元素在富Ni区显著聚集,富Ni区的Cr含量显著增高。随着Mn含量的增加,基体上结节状富Ni相(γ2)和富Cr相尺寸减小,分布更加均匀,大量细小富Cr第二相的存在显著提升了合金的力学性能。当Mn含量为3%时,小尺寸富Cr第二相开始在晶界处偏聚形成链状结构,对合金的力学性能产生了不利影响。当Mn含量为7%时,Mn原子固溶强化及第二相细化效果显著,合金的力学性能最佳,其硬度和抗拉强度分别为195.06 HB和401 MPa。 展开更多
关键词 Cu-ni-Cr-xMn合金 显微组织 性能
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基于机器学习的Cu-Ni-Co-Si合金固溶处理晶粒尺寸预测 被引量:1
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作者 闫碧霄 朱雪彤 +1 位作者 吴钢 陈慧琴 《铜业工程》 CAS 2024年第2期18-22,共5页
Cu-Ni-Co-Si合金在固溶处理后的晶粒尺寸会影响其服役性能。采用3种不同的机器学习方法——BP神经网络、随机森林、长短期记忆网络,分别建立了Cu-Ni-Co-Si合金固溶温度和固溶时间对固溶后晶粒尺寸影响的机器学习预测模型。对比分析3种... Cu-Ni-Co-Si合金在固溶处理后的晶粒尺寸会影响其服役性能。采用3种不同的机器学习方法——BP神经网络、随机森林、长短期记忆网络,分别建立了Cu-Ni-Co-Si合金固溶温度和固溶时间对固溶后晶粒尺寸影响的机器学习预测模型。对比分析3种不同机器学习模型的预测精度,发现BP神经网络模型预测精度最高,其平均相对误差为8.55%。随后采用遗传算法优化BP神经网络。结果表明,所建立的BPGA模型平均相对误差比BP神经网络模型降低了6.47个百分点,其平均相对误差为2.08%,能够有效地为Cu-Ni-Co-Si合金固溶处理工艺参数的选择提供指导。 展开更多
关键词 Cu-ni-Co-Si合金 固溶处理 工艺参数 晶粒尺寸 机器学习
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Al-Si-Cu-Ni钎料成分和钎焊温度对高硅铝合金/可伐合金钎焊接头性能的影响
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作者 邱玉洁 牛济泰 +1 位作者 杨环宇 木二珍 《机械工程材料》 CAS CSCD 北大核心 2024年第11期103-110,共8页
采用甩带工艺制备Al-7.5Si-23Cu-xNi(x取0,0.5,1.0,1.5,2.0,2.5,质量分数/%)箔状钎料,研究了镍含量对钎料组织和性能的影响;利用性能最好的钎料对CE11高硅铝合金和4J29可伐合金进行真空钎焊,分析了钎焊温度(560~600℃)对接头组织、抗剪... 采用甩带工艺制备Al-7.5Si-23Cu-xNi(x取0,0.5,1.0,1.5,2.0,2.5,质量分数/%)箔状钎料,研究了镍含量对钎料组织和性能的影响;利用性能最好的钎料对CE11高硅铝合金和4J29可伐合金进行真空钎焊,分析了钎焊温度(560~600℃)对接头组织、抗剪强度及气密性的影响。结果表明:随着镍含量的增加,钎料的液/固相线变化较小,熔化温度区间较稳定,铸态钎料局部共晶组织增多,柱状晶变粗大,断裂应变和接头的抗剪强度均先升高后降低;当镍质量分数为2.0%时,钎料的熔化温度区间最小,熔点最低,组织均匀,共晶相较多且弥散分布,钎料的韧性和焊接性能最好。当钎焊温度低于570℃时,Al-7.5Si-23Cu-2.0Ni钎料熔化不完全,与母材结合较差;当钎焊温度高于570℃时,钎料与母材间的元素互扩散剧烈,造成硅相聚集,焊缝中出现裂纹。随着钎焊温度的升高,接头的抗剪强度先升后降,焊后泄漏率先降后升。最佳钎焊温度为570℃,此时焊缝与两侧母材结合紧密,元素扩散均匀,接头的抗剪强度最大,气密性最好。 展开更多
关键词 高硅铝合金 可伐合金 Al-Si-Cu-ni钎料 钎焊温度 抗剪强度
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轧制形变热处理对Cu-Ni-Si系合金性能和微结构的影响
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作者 郑鑫祥 张学宾 +5 位作者 周延军 柳亚辉 杜宜博 岳鹏飞 鲁长建 刘爱奎 《铜业工程》 CAS 2024年第5期11-20,共10页
对比了Cu-Ni-Si合金二次固溶态(790℃×120 min)和大变形冷轧(98.42%累积变形量)+二次时效态(420℃×480 min)的强度、硬度、导电率等性能的变化规律,分析了两种不同形变热处理工艺状态下合金的显微组织和断口形貌。结果表明:... 对比了Cu-Ni-Si合金二次固溶态(790℃×120 min)和大变形冷轧(98.42%累积变形量)+二次时效态(420℃×480 min)的强度、硬度、导电率等性能的变化规律,分析了两种不同形变热处理工艺状态下合金的显微组织和断口形貌。结果表明:大变形冷轧+二次时效工艺条件下制备的合金平均晶粒尺寸为4.28μm;析出相主要由Cr3Si与Ni2Si构成,平均尺寸分别为65 nm和11 nm,呈弥散分布,且合金内出现大量纳米孪晶。累积大变形产生的形变强化和弥散分布的纳米级析出相形成的析出强化,以及大量纳米孪晶的形成,是Cu-Ni-Si合金力学性能显著提升的主要因素。大变形冷轧+二次时效处理后的合金导电率、硬度、抗拉强度、屈服强度分别为27.2%IACS,HV 231.98,707 MPa,703MPa,较二次固溶态合金分别提升了32.60%,94.67%,204.74%,575.96%。二次固溶态合金断口形貌主要由大而深的韧窝组成,大变形冷轧+二次时效态合金断口形貌主要由小而浅的韧窝组成,数量较多,分布致密。 展开更多
关键词 Cu-ni-SI合金 形变热处理 析出相 纳米孪晶 力学性能
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铸态Cu-1.16Ni-0.36Cr合金热变形行为及热加工图
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作者 孙文明 李韶林 +3 位作者 宋克兴 王强松 丁宗业 朱莹莹 《材料导报》 EI CSCD 北大核心 2024年第2期220-227,共8页
利用Gleeble-1500型热模拟试验机,研究了Cu-1.16Ni-0.36Cr合金在变形量为50%、变形温度为750~950℃、变形速率为0.01~10 s^(-1)下的热压缩变形行为,建立该合金热变形的本构方程和热加工图。结果表明:Cu-1.16Ni-0.36Cr合金在700~900℃的... 利用Gleeble-1500型热模拟试验机,研究了Cu-1.16Ni-0.36Cr合金在变形量为50%、变形温度为750~950℃、变形速率为0.01~10 s^(-1)下的热压缩变形行为,建立该合金热变形的本构方程和热加工图。结果表明:Cu-1.16Ni-0.36Cr合金在700~900℃的变形温度下以动态回复为主,在950℃下发生完全的动态再结晶。通过真应力应变曲线得到了该合金热变形的本构方程和热加工图。根据应变对流变应力的影响对本构方程进行修正,通过修正后的回归方程对流变应力进行模拟,模拟结果与实验结果吻合。热加工图表明,该合金适宜的热变形工艺参数为900~950℃和0.1~1 s^(-1),其中950℃和1 s^(-1)变形条件下组织状态最佳,为晶粒细小均匀的等轴晶。 展开更多
关键词 Cu-ni-Cr合金 热压缩变形 本构方程 热加工图 动态再结晶
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Effects of Ni content on the cast and solid-solution microstructures of Cu-0.4wt% Be alloys 被引量:6
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作者 Shuang-jiang He Yan-bin Jiang +2 位作者 Jian-xin Xie Yong-hua Li Li-juan Yue 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第6期641-651,共11页
The effects of Ni content(0–2.1wt%)on the cast and solid-solution microstructures of Cu-0.4wt%Be alloys were investigated,and the corresponding mechanisms of influence were analyzed.The results show that the amount... The effects of Ni content(0–2.1wt%)on the cast and solid-solution microstructures of Cu-0.4wt%Be alloys were investigated,and the corresponding mechanisms of influence were analyzed.The results show that the amount of precipitated phase increases in the cast alloys with increasing Ni content.When the Ni content is 0.45wt%or 0.98wt%,needle-like Be_(21)Ni_5 phases form in the grains and are mainly distributed in the interdendritic regions.When the Ni content is 1.5wt%or greater,a large number of needle-like precipitates form in the grains and chain-like Be_(21)Ni_5 and Be Ni precipitates form along the grain boundaries.The addition of Ni can substantially refine the cast and solid-solution microstructures of Cu-0.4wt%Be alloys.The hindering effects of both the dissolution of Ni into the matrix and the formation of Be–Ni precipitates on grain-boundary migration are mainly responsible for refining the cast and solid-solution microstructures of Cu-0.4wt%Be alloys.Higher Ni contents result in finer microstructures;however,given the precipitation characteristics of Be–Ni phases and their dissolution into the matrix during the solid-solution treatment,the upper limit of the Ni content is 1.5wt%–2.1wt%. 展开更多
关键词 beryllium-copper alloys ALLOYING ni content microstJ-ucture solid-solution treatment
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Effect of praseodymium substitution for lanthanum on structure and properties of La_(0.65-x)Pr_xNd_(0.12)Mg_(0.23)Ni_(3.4)Al_(0.1)(x=0.00–0.20) hydrogen storage alloys 被引量:7
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作者 闫慧忠 孔繁清 +2 位作者 熊玮 李宝犬 李金 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第2期244-249,共6页
In order to investigate the effect of substituting La with Pr on structural and hydrogen storage properties of La-Mg-Ni system (AB3.5-type) hydrogen storage alloys, a series of La0.65-xPrxNd0.12Mg0.23Ni3.4Al0.1(x=0... In order to investigate the effect of substituting La with Pr on structural and hydrogen storage properties of La-Mg-Ni system (AB3.5-type) hydrogen storage alloys, a series of La0.65-xPrxNd0.12Mg0.23Ni3.4Al0.1(x=0, 0.10, 0.15, 0.2) hydrogen storage alloys were prepared. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) analyses revealed that two alloys (x=0.0 and 0.10) were composed of (La,Mg)2(Ni,Al)7 phase, La(Ni,A1)5 phase and (La,Mg)Ni2 phase, while other alloys (x=0.15 and 0.20) consisted of (La,Mg)2(Ni,A1)7 phase, La(Ni,A1)5 phase, (La,Mg)Ni2 phase and (La,Mg)(Ni,A1)3 phase. All alloys showed, however, only one pressure plateau in P-C isotherms. The Pr/La ratio in alloy composition influenced hydrogen storage capacity and kinetics properties. Electrochemical studies showed that the discharge capacity decreased from 360 mAh/g (x=-0.00) to 335 mAh/g (x=-0.20) as x increased. But the high-rate dischargeability (HRD) of alloy electrodes increased from 26% (x=0.00) to 56% (x=-0.20) at a discharge current density of Id=1800 mA/g. Anode polarization measurements were done to further understand the electrochemical kinetics properties after Pr substitution. 展开更多
关键词 hydrogen storage alloy La-Mg-ni system metal hydrides MH/ni batteries electrochemical properties rare earths
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Sn和Ni对过冷Ag-28.1Cu共晶合金凝固组织的影响
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作者 李宏 金青林 林水根 《材料科学与工艺》 CAS CSCD 北大核心 2024年第5期50-57,共8页
为了揭示在共晶相中具有不同固溶度的Sn和Ni元素对过冷共晶凝固组织的影响和作用机理,使用熔融玻璃净化和循环过热相结合的方法制备了过冷Ag-28.1Cu-xM(x=0%0.5%、1%,质量分数;M=Sn,Ni)共晶合金试样,分析了第3组元Sn和Ni对过冷Ag-Cu共... 为了揭示在共晶相中具有不同固溶度的Sn和Ni元素对过冷共晶凝固组织的影响和作用机理,使用熔融玻璃净化和循环过热相结合的方法制备了过冷Ag-28.1Cu-xM(x=0%0.5%、1%,质量分数;M=Sn,Ni)共晶合金试样,分析了第3组元Sn和Ni对过冷Ag-Cu共晶合金凝固组织的影响。结果表明添加Sn元素不会改变宏观组织的分区特征,微观组织中出现反常共晶增多和粗化的现象,并具有随机的取向分布。凝固过程中Sn会形成垂直于固-液界面的浓度梯度,造成胞状界面失稳形成树枝状,但仍能够维持耦合共晶生长。而添加Ni元素会使宏观组织的分区特征消失,微观组织中则出现了单相枝晶,且表现出单一取向分布,原因是第3组元Ni平行于固-液界面扩散,使共晶合金生长方式从耦合生长转变为离异生长。 展开更多
关键词 Ag-28.1Cu共晶合金 深过冷 合金元素Sn和ni 凝固组织 EBSD
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Si的添加对Cu-Ni-Al合金显微组织和性能的影响
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作者 丁炜 程建奕 +1 位作者 刘领 余方新 《材料热处理学报》 CAS CSCD 北大核心 2024年第4期48-60,共13页
Cu-Ni-Al合金作为一种超高强、导电的弹性铜合金,在电子工业、航空航天、仪器仪表等方面应用广泛。利用光学显微镜(OM)、扫描电镜(SEM)、X射线衍射仪(XRD)和扫描透射电镜(STEM)对Cu-6Ni-2.76Al和Cu-6Ni-2.76Al-0.4Si合金时效后的显微组... Cu-Ni-Al合金作为一种超高强、导电的弹性铜合金,在电子工业、航空航天、仪器仪表等方面应用广泛。利用光学显微镜(OM)、扫描电镜(SEM)、X射线衍射仪(XRD)和扫描透射电镜(STEM)对Cu-6Ni-2.76Al和Cu-6Ni-2.76Al-0.4Si合金时效后的显微组织进行了研究。结果表明:Cu-6Ni-2.76Al合金在经过900℃×12 h均匀化退火+80%热轧变形+950℃×2 h固溶+50%冷轧变形+500℃×8 h时效处理后的综合性能较好,硬度为279.5 HV0.3,导电率为16.14%IACS,合金的强化相为纳米级球状颗粒γ′-Ni3Al相;Cu-6Ni-2.76Al-0.4Si合金在经过900℃×12 h均匀化退火+80%热轧变形+950℃×2 h固溶+50%冷轧变形+450℃×2 h时效处理后的综合性能优异,硬度为313.2 HV0.3,导电率为13.24%IACS,合金的强化相为纳米级颗粒γ′-Ni3Al相和δ-Ni2Si相。Si元素的添加对合金的导电率影响不大,但显著地提高了其峰值硬度,且缩短了达到硬度峰值所需要的时效时间,但也使得合金抗过时效能力下降。γ′-Ni3Al和δ-Ni2Si强化相与Cu基体的位向关系分别为:[001]_(Cu)∥[001]_(Ni_(3)Al)∥[001]_(δ);(110)_(Cu)∥(110)_(Ni_(3)Al)∥(100)_(δ);(110)_(Cu)∥(110)_(Ni_(3)Al)∥(010)_(δ)。沉淀强化作用对合金性能的提升最显著。 展开更多
关键词 Cu-ni-Al合金 时效处理 导电率 硬度 沉淀强化
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