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Geochemical Characteristics,Genesis of Concealed Cu-rich Ore Body in the Jinchuan Deposit,Northwestern China,and Its Prospecting 被引量:9
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作者 GAO Yalin TANG Zhongli +2 位作者 ZHANG Mingjie TIAN Yulong XIAO Lizhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第6期1085-1100,共16页
The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the thirdlargest magmatic sulfide Ni-Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and ... The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the thirdlargest magmatic sulfide Ni-Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and the border of the deposit becomes more and more important. The ore body, ore and geochemistry characteristics of the concealed Cu-rich ore body are researched. Through spatial analysis and comparison with the neighboring II1 main ore body, the mineralization rule of the concealed Cu-rich ore body is summed up. It is also implied that Cu-rich magma may exist between Nirich magma and ore pulp during liquation differentiation in deep-stage chambers, which derives from deep-mantle Hi-MgO basalt magma. It is concluded that the type of ore body has features of both magmatic liquation and late reconstruction action. It has experienced three stages: deep liquation and pulsatory injection of the Cu- and PPGE-rich magma, concentration of tectonic activation, and the later magma hydrothermal superimposition. In addition, the Pb and S isotopes indicate the magma of I6 concealed Cu-rich ore body originates predominantly from mantle; however, it is interfused by minute crust material. Finally, it is inferred that the genesis of the Cu-Ni sulfide deposit is complex and diverse, and the prospect of seeking new deep ore bodies within similar deposits is promising, especially Cu-rich ore bodies. 展开更多
关键词 Cu-Ni sulfide deposit cu-rich magma cu-rich ore body PROSPECTING Jinchuan
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Study of Cu-rich phase precipitation in austenitic antibacterial stainless steel 被引量:1
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作者 REN Ling and YANG Ke Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,Liaoning,China 《Baosteel Technical Research》 CAS 2010年第S1期76-,共1页
Cu precipitation behaviors in two Cu-bearing austenitic antibacterial stainless steels,type 304 and type 317L,were systematically studied by using relatively simple methods for materials analysis,including micro-hardn... Cu precipitation behaviors in two Cu-bearing austenitic antibacterial stainless steels,type 304 and type 317L,were systematically studied by using relatively simple methods for materials analysis,including micro-hardness,electrical resistivity,electrochemical impedance spectroscopy,X-ray diffraction and differential scanning calorimetry.The results indicated that after aging at elevated temperature,the micro-hardness, electrical resistivity,electrochemical impedance and lattice constant of the steel were all varied at different degrees due to the precipitation and growth of Cu-rich phases.The results also showed that the heat evolution during the process of Cu precipitation could be sensitively detected by means of differential scanning calorimetry,obtainning the starting temperature,peak temperature,peak area of the Cu-rich precipitation,and even the activation energy by calculation.The results confirmed that the Cu-rich phased precipitation in the Cu-bearing austenitic antibacterial stainless steel should be a thermal activation process controlled by Cu diffusion.All the materials analysis methods used in this study can be more simple and effective for application in R & D of the Cu-bearing antibacterial stainless steels. 展开更多
关键词 antibacterial stainless steel cu-rich phases AGING Cu precipitation.
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BEHAVIOUR OF Co_5Cr_3Si_2 PHASE IN Cu-RICH ALLOYS CONTAINING Co,Cr AND Si
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《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第9期213-215,共3页
The major phases in the Cu-rich alloys containing Co,Cr and Si are α-Cu(a solid solution of Co,Cr and Si in Cu),χ-phase(Co_5Cr_3Si_2)and Co_2Si.In comparison with reference sample,it has been detected that the cryst... The major phases in the Cu-rich alloys containing Co,Cr and Si are α-Cu(a solid solution of Co,Cr and Si in Cu),χ-phase(Co_5Cr_3Si_2)and Co_2Si.In comparison with reference sample,it has been detected that the crystal structure of Co_5Cr_3Si_2 is cubic,α-Mn type with a=0.8694 nm.The melting temperature of χ-phase and the alloy are higher than that of the pure Cu,namely,1535 and 1389 K respectively.During ageing treatment,the Co_2Si phase precipitates out from α-Cu and χ-phase simultaneously,but the hardening effect is mainly contributed by the precipitation from α-Cu. 展开更多
关键词 cu-rich alloy X-phase
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新疆东天山黄滩金铜锌矿成矿时代——来自白云母^(40)Ar-^(39)Ar年龄和黄铁矿Re-Os年龄约束
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作者 耿新霞 张志欣 +4 位作者 张振龙 李宁 杨富全 杨成栋 成曦晖 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第2期368-379,共12页
卡拉塔格是东天山十分重要的铜矿集区,发育5个不同时代和成矿类型的成矿系统。近年来新发现了黄滩(包括金岭)金铜锌矿床,赋存于火山岩系中,发育层状矿化、脉状矿化和黄铁绢英岩化,但层状矿化和黄铁绢英岩化形成时代不清楚,制约了进一步... 卡拉塔格是东天山十分重要的铜矿集区,发育5个不同时代和成矿类型的成矿系统。近年来新发现了黄滩(包括金岭)金铜锌矿床,赋存于火山岩系中,发育层状矿化、脉状矿化和黄铁绢英岩化,但层状矿化和黄铁绢英岩化形成时代不清楚,制约了进一步找矿勘查工作。本文基于野外调查和室内研究,开展白云母^(40)Ar-^(39)Ar年龄和黄铁矿Re-Os年代学研究,获得黄铁绢英岩中白云母^(40)Ar-^(39)Ar坪年龄为429.46±3.91 Ma,7件层状矿化中黄铁矿Re-Os等时线年龄为436.5±4.2 Ma。层状矿化年龄与前人获得含矿岩系英安岩和英安质凝灰岩年龄(434~438 Ma)、脉状矿化年龄(432~438 Ma)一致,表明层状矿化、脉状矿化和黄铁绢英岩化是同一成矿事件的产物,黄滩为富金火山成因块状硫化物(VMS)型矿床。因此,尽管黄滩和红海‒黄土坡为VMS型矿床,红石为火山热液脉状矿床,但它们均为同一VMS成矿系统,形成于430~439 Ma,受控矿因素的差异,造成了成因类型、矿化类型和成矿元素组合的多样性。 展开更多
关键词 白云母^(40)Ar-^(39)Ar年龄 黄铁矿Re-Os年龄 VMS矿床 金铜锌 黄滩 东天山
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贝氏体钢时效处理富Cu团簇析出特点及其第一性原理计算
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作者 杨劼 任慧平 +2 位作者 王海燕 高雪云 刘宗昌 《材料导报》 EI CAS CSCD 北大核心 2024年第14期232-238,共7页
研究低碳贝氏体钢(15Cr12CuSiMoMn)时效处理过程中富Cu团簇的析出演变特点,并基于第一性原理计算,采用特殊准随机结构(Special quasirandom structures,SQS)、Solid-State Nudged Elastic Band(SSNEB)方法构建Fe-Cu二元体系的无序固溶... 研究低碳贝氏体钢(15Cr12CuSiMoMn)时效处理过程中富Cu团簇的析出演变特点,并基于第一性原理计算,采用特殊准随机结构(Special quasirandom structures,SQS)、Solid-State Nudged Elastic Band(SSNEB)方法构建Fe-Cu二元体系的无序固溶体结构模型,模拟计算相变能量路径,分析并表征析出相析出演变规律与模拟计算之间的相互联系。结果表明,实验钢在指定温度(500℃)进行时效热处理,时效处理各阶段实验钢中弥散析出约2.6~53 nm的富Cu团簇,以共格、非共格状态存在于基体中,经模拟计算,BCC-Cu向9R-Cu转变过程中需在开始阶段克服8.9 meV的能垒,之后从9R-Cu向孪晶FCC-Cu+9R-Cu结构转变过程中需要克服4.9 meV的能垒,非稳态BCC富Cu团簇与稳定态的FCC Cu之间具有0.14 eV/atom的形成能差,当Cu含量超过21.6%(原子分数)后,富Cu团簇从BCC结构不断向稳定的纯FCC-Cu结构演变。从能量角度分析了富Cu团簇析出倾向,解释了富Cu团簇的析出惯序,有利于优化贝氏体组织,为含Cu贝氏体沉淀钢的深入研究及相关领域的开发拓展提供理论参考依据。 展开更多
关键词 15Cr12CuSiMoMn钢 富Cu团簇 时效处理 结构转变
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Effect of Cu Content on Aging Precipitation Behaviors of Cu-Rich Phase in Fe-Cr-Ni Alloy 被引量:10
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作者 TAN Shu-ping WANG Zhen-hua +3 位作者 CHENG Shi-chang LIU Zheng-dong HAN Jie-cai FU Wan-tang 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2010年第5期63-68,共6页
The precipitation characteristics and effect on strengthening mechanism of Cu-rich phases during short-time and long-time aging for Super 304H steels with different Cu content were investigated using X-ray diffraction... The precipitation characteristics and effect on strengthening mechanism of Cu-rich phases during short-time and long-time aging for Super 304H steels with different Cu content were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show that the size of Cu-rich phase particles increases, the interspace of Cu-rich phase particles decreases and the density of Curich phases increases with the increase of Cu content during short-time aging (approximately 800 h) at 650℃ for Super 304H steels. During long-time aging (more than 2 000 h) at 650 ℃, Cu-rich phase precipitates sufficiently and the strengthening effect of Cu-rich phase is preferable in Super 304H steel containing Cu of 4%. The strengthening effect of Cu-rich phase in Super 304H steels containing Cu of 2.2% or 5% is weaker than that with Cu of 4% during long-time aging (more than 2 000 h). 展开更多
关键词 heat resistant alloy Cu content cu-rich phase AGING precipitation strengthening
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Crystal Structure Evolution of the Cu-rich Nano Precipitates from bcc to 9R in Reactor Pressure Vessel Model Steel 被引量:7
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作者 Liu FENG Bangxin ZHOU +1 位作者 Jianchao PENG Junan WANG 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2013年第6期707-712,共6页
The crystal structure evolution of the Cu-rich nano precipitates from bcc to 9R during thermal aging was studied in nuclear reactor pressure vessel (RPV) model steels. The specimens, contained higher copper and nick... The crystal structure evolution of the Cu-rich nano precipitates from bcc to 9R during thermal aging was studied in nuclear reactor pressure vessel (RPV) model steels. The specimens, contained higher copper and nickel contents than commercially available one, were heated at 890 ~C for 0.5 h and then water quenched followed by tempering at 0(50 ~C for I0 h and aging at 400 ~C for 1000 h. It was observed that bcc and 9R orthogonal structure, as well as 9R orthogonal and 9R monoclinic structure, coexist in a single Cu-rich nano precipitate. Further analyses pointed out that Cu-rich nano precipitates of bcc structure were not stable, it may preferentially transform to 9R orthogonal structure and then to 9R monoclinic structure. This results showed that the crystal structure evolution of the Cu-rich nano precipitates was complex. 展开更多
关键词 Reactor pressure vessel model steel Thermal aging cu-rich nano precip-itates Structure evolution HRTEM
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Strengthening effect of Cu-rich phase precipitation in 18Cr9Ni3CuNbN austenitic heat-resisting steel 被引量:6
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作者 Chengyu CHI Hongyao YU +4 位作者 Jianxin DONG Xishan XIE Zhengqiang CUI Xiaofang CHEN Fusheng LIN 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2011年第2期141-147,共7页
The Cu-containing austenitic heat-resistant steel 18Cr9Ni3CuNbN, which is being used as superheater and reheater tube material for modern ultra-super-critical (USC) power plants all over the world, has been investig... The Cu-containing austenitic heat-resistant steel 18Cr9Ni3CuNbN, which is being used as superheater and reheater tube material for modern ultra-super-critical (USC) power plants all over the world, has been investigated at 650 ℃ long time aging till 10 000 h. SEM, TEM and 3DAP (three dimensional atom probe) have been used to follow microstructural changes with mechanical property variations. Experimental results show that Cu-rich phase and MX precipitate in the grains as well as M 23 C 6 precipitates at grain boundaries are the main precipitation strengthening phases in this steel. Among them Cu-rich phase is the most important strengthening phase. Homogeneous distribution of very fine nano-size Cu-rich phase has been formed at very early stage of 650 ℃ aging (less than 1 h). Cu atoms gradually concentrate to Cu-rich particles and the other elements (such as Fe, Cr, Ni etc) diffuse away from Curich particles to γ-matrix with the increasing of aging time at 650 ? C. The growth rate of Cu-rich phase at 650 ℃ long time aging is very slow and the average diameters of Cu-rich phase have been determined by TEM method. Cu-rich phase keeps in about 30 nm till 650 ℃ aging for 10 000 h. It shows that nano-size Cu-rich phase precipitation strengthening can be kept for long time aging at 650 ℃ because of its excellent stability at high temperatures. According to structure stability study and mechanical properties determination results the Cu-rich phase precipitation sequence and its strengthening mechanism model have been suggested and discussed. 展开更多
关键词 Austenitic heat-resistant steel Precipitation strengthening cu-rich phase MX M 23 C 6
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Compositional Variants of Cu-rich Precipitate in Thermally Aged Ferritic Steel 被引量:3
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作者 Qingdong Liu Yihua Chen +1 位作者 Chuanwei Li Jianfeng Gu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2018年第5期465-470,共6页
Atom probe tomography was utilized to investigate Cu precipitation in a high-strength low-alloy steel isothermally aged at 500℃ for 1, 4, 16, and 64 h after water-quenching from 900℃. With prolonged aging time, the ... Atom probe tomography was utilized to investigate Cu precipitation in a high-strength low-alloy steel isothermally aged at 500℃ for 1, 4, 16, and 64 h after water-quenching from 900℃. With prolonged aging time, the Curich precipitates(CRPs) increased in size and decreased in number density, and gradually evolved from spheroidal to elliptical in morphology. The small CRPs were rich in a high amount of Fe and a certain amount of Ni and Mn at their early nucleation stage. The large CRPs with increased size due to extensive aging contained less Fe and more Cu at their later growth stage. Additionally, Ni and Mn were both readily to segregate at the CRP/matrix heterophase interfaces, and Mn was higher in content than Ni in the precipitate interior especially when the CRPs were large in size. 展开更多
关键词 High-strength low-alloy steel Thermal aging cu-rich precipitate Atom probe tomography
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Ni-Based Metallic Glass Composites Containing Cu-Rich Crystalline Nanospheres 被引量:1
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作者 Yao-Yao Xi Jie He +4 位作者 Xiao-Jun Sun Wang Li Jiu-Zhou Zhao Hong-Ri Hao Ting Xiong 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2018年第11期1130-1136,共7页
In this work, a quaternary Ni-Cu-Nb-Ta system has been designed to obtain composite microstructure with sphericalcrystalline Cu-rich particles embedded in amorphous Ni-rich matrix. The alloy samples were prepared by u... In this work, a quaternary Ni-Cu-Nb-Ta system has been designed to obtain composite microstructure with sphericalcrystalline Cu-rich particles embedded in amorphous Ni-rich matrix. The alloy samples were prepared by using single-roller melting-spinning method. The microstructure and thermal properties of the as-quenched alloy samples were char-acterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, anddifferential scanning calorimetry. It shows that the spherical crystalline Cu-rich particles are embedded in the amorphousNi-rich matrix. The average size of the Cu-rich particles is strongly dependent upon the Cu content. The effect of the alloycomposition on the behavior of liquid-liquid phase separation and microstructure evolution was discussed. The phaseformation in the Ni-based metallic glass matrix composite was analyzed. 展开更多
关键词 Phase separation Immiscible alloys Metallic glass matrix composites Ni-based metallic glasses cu-rich nanoparticles
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中非赞比亚成矿带卢安夏盆地富钴矿物特征及其指示意义
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作者 卢宜冠 涂家润 +5 位作者 孙凯 任军平 方科 覃鹏 郭虎 和文言 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第6期1853-1869,共17页
中非铜钴成矿带是全球规模最大、平均品位最高的沉积型铜钴成矿带,在全球钴矿产供应中占有极其重要的地位。卢安夏矿床是中非赞比亚成矿带一超大型铜(钴)矿床,但目前对于其钴的富集机制及成因模式尚不清楚。本研究聚焦于卢安夏铜钴矿床... 中非铜钴成矿带是全球规模最大、平均品位最高的沉积型铜钴成矿带,在全球钴矿产供应中占有极其重要的地位。卢安夏矿床是中非赞比亚成矿带一超大型铜(钴)矿床,但目前对于其钴的富集机制及成因模式尚不清楚。本研究聚焦于卢安夏铜钴矿床中硫铜钴矿、黄铁矿等富钴矿物,对其开展电子探针、微区X射线荧光光谱分析和S同位素分析。电子探针与微区X射线荧光光谱分析显示,卢安夏矿床中存在沉积期(Py1)、成岩期(Py2)、热液期(Py3)、表生期(Py4)四期黄铁矿。其中,钴主要富集在硫铜钴矿-黄铁矿-黄铜矿-石英脉的Py3中,其钴含量最高可达10.5%;其次为表生期黄铁矿(Py4),但其钴富集程度有限。黄铁矿Co、As含量显示富钴Py3的形成与含As流体不断与围岩发生作用有关。尽管卢安夏硫化物S同位素组成变化范围较大,但富钴的黄铁矿δ^(34)S为负值(-9.6‰~-2.8‰),且全岩钴含量与单矿物δ^(34)S值呈负相关关系。这一结果指示富钴硫化物的形成源于在热液提供热量的条件下,有机质热分解产生大量强还原性物质与硫酸盐发生反应,由此促进了硫酸盐的还原过程和硫化物的沉淀。结合近年来中非铜钴成矿带的地质演化史和钴富集机制方面的研究成果,卢安夏矿床钴的主要成矿期应为卢菲利安造山期(540~490Ma),在此造山阶段释放的氧化性高温高盐热液是钴的主要载体,而卢安夏矿床钴的富集可能源于赋矿地层中丰富的有机质成分为钴的富集成矿提供了有利条件,热液注入后由于氧逸度的降低,钴在相对低温的条件下发生沉淀而形成矿床。 展开更多
关键词 铜钴矿床 富钴矿物 成因机制 中非铜钴带
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Effect of Nanoscale Cu-Riched Clusters on Strength and Impact Toughness in a Tempered Cu-Bearing HSLA Steel 被引量:1
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作者 Yubin Du Xiaofeng Hu +2 位作者 Yuanyuan Song Yangpeng Zhang Lijian Rong 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2022年第4期537-550,共14页
The effect of Cu-riched clusters on strength and impact toughness in a tempered Cu-bearing high-strength low-alloy(HSLA)steel is investigated. With increasing the tempering temperature, it is found that the yield stre... The effect of Cu-riched clusters on strength and impact toughness in a tempered Cu-bearing high-strength low-alloy(HSLA)steel is investigated. With increasing the tempering temperature, it is found that the yield strength increases firstly, achieving the maximum value(~ 1053 MPa) at the tempering temperature of 450 ℃, and then decreases significantly with the rise of tempering temperature. The tempering temperature-dependent yield strength is closely related to the precipitation of Cu-riched clusters. When tempering at 450 ℃, the peak strength will be reached as the nanoscale Cu-riched clusters with small size and high number density will cause a strong precipitation strengthening(~ 492 MPa) due to the dislocation shearing mechanism. However, the Cu-riched clusters will coarsen with further increasing tempering temperature, resulting in obvious decrement of yield strength owing to the dislocation bypassing mechanism. Compared with the yield strength,the variation in impact energy displays an inverse tendency and the impact energy is only 7 J for the sample tempered at 450 ℃. The fracture mode can be well explained by the competition between the cleavage fracture strength( σ F) and “yield strength”( σ Y). Although transgranular cleavage fracture can be found in samples tempered at 450 and 550 °C, the crack propagation along the lath boundaries is prevented in the sample tempered at 550 ℃. The reason is that the number density of Cu-riched clusters at lath boundaries decreases and the segregation of Mo element at the lath boundaries is induced,which will increase the bonding energy. 展开更多
关键词 High-strength low-alloy(HSLA)steel cu-riched cluster Strengthening mechanism Lath boundary Impact energy
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新疆西天山喇嘛苏铜锌矿床矽卡岩矿物学与还原性流体演化
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作者 李文广 申萍 潘鸿迪 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第3期927-949,共23页
喇嘛苏铜锌矿位于中亚成矿域西段,为新疆西天山地区相对较早发现的斑岩-矽卡岩铜锌矿床。本文对喇嘛苏铜锌矿矽卡岩和矽卡岩化大理岩中的矽卡岩矿物进行了岩相学及主微量成分分析,首次发现了喇嘛苏铜锌矿床发育的黑榴石和富钛钙铝榴石... 喇嘛苏铜锌矿位于中亚成矿域西段,为新疆西天山地区相对较早发现的斑岩-矽卡岩铜锌矿床。本文对喇嘛苏铜锌矿矽卡岩和矽卡岩化大理岩中的矽卡岩矿物进行了岩相学及主微量成分分析,首次发现了喇嘛苏铜锌矿床发育的黑榴石和富钛钙铝榴石。对矽卡岩中发育震荡环带的钙铁榴石进行主量元素和电子探针mapping分析,发现钙铁榴石发育不均一的核部,环带部分表现为Al-Fe元素此消彼长的耦合震荡关系;对钙铁榴石从核部中央向边缘环带进行定向原位微量元素LA-ICPMS分析,发现∑REE表现为连续略有降低的趋势、δEu表现出震荡变化。黑榴石和富钛钙铝榴石表现为核幔结构,显示流体氧逸度的降低,流体从超常富集Ti转变为富集Ti。对富钛钙铝榴石进行原位微量元素LA-ICPMS测试,发现富钛钙铝榴石∑REE高于钙铁榴石(钙铝榴石:58.4×10^(-6)~408.4×10^(-6);钙铁榴石28.2×10^(-6)~108.7×10^(-6)),富钛钙铝榴石具有强烈正Eu异常(δEu=11.3~15.0),钙铁榴石和富钛钙铝榴石均表现为富集轻稀土而亏损重稀土。喇嘛苏铜锌矿中的原生辉石为透辉石,后经退蚀变流体交代发生Mg元素丢失和Fe元素富集,转变为次透辉石-铁次透辉石,随交代程度加深,进一步转变为铁角闪石,最后在退蚀变流体中直接沉淀出铁镁钙闪石。在背散射下,原生透辉石、次透辉石-铁次透辉石、铁角闪石、铁镁钙闪石表现为亮度不同的明暗结构。矽卡岩矿物的显微结构和主微量成分表明,蚀变流体为酸性和富Cl、REE、Ti的流体,蚀变阶段早期为氧化性流体,晚期为还原性流体。喇嘛苏铜锌矿流体中CH_(4)、C_(2)H_(6)等还原性物质、共生的磁黄铁矿-磁铁矿低氧逸度组合及还原状态矽卡岩矿物组合表明喇嘛苏铜锌矿可能为一还原性斑岩-矽卡岩铜锌矿。 展开更多
关键词 还原性黑榴石 富钛钙铝榴石 核幔结构 喇嘛苏铜锌矿
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Effect of Cu-Rich Phase Precipitation on the Microstructure and Mechanical Properties of CoCrNiCux Medium-Entropy Alloys Prepared via Laser Directed Energy Deposition
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作者 Yong Xie Zhixin Xia +3 位作者 Jixin Hou Jiachao Xu Peng Chen Le Wan 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2021年第11期1591-1600,共10页
CoCrNiCux(x=0.16,0.33,0.75,and 1)without macro-segregation medium-entropy alloys(MEAs)was prepared using laser directed energy deposition(LDED).The microstructure and mechanical properties of CoCrNiCux alloys with inc... CoCrNiCux(x=0.16,0.33,0.75,and 1)without macro-segregation medium-entropy alloys(MEAs)was prepared using laser directed energy deposition(LDED).The microstructure and mechanical properties of CoCrNiCux alloys with increasing Cu content were investigated.The results indicate that a single matrix phase changes into a dual-phase structure and the tensile fracture behaviors convert from brittle to plastic pattern with increasing Cu content in CoCrNiCux alloys.In addition,the tensile strength of CoCrNiCux alloys increased from 148 to 820 MPa,and the ductility increased from 1 to 11%with increasing Cu content.The nano-precipitated particles had a mean size of approximately 20 nm in the Cu-rich phase area,and a large number of neatly arranged misfit dislocations were observed at the interface between the two phases due to Cu-rich phase precipitation in the CoCrNiCu alloy.These misfit dislocations hinder the movement of dislocations during tensile deformation,as observed through transmission electron microscopy.This allows the CoCrNiCu alloy to reach the largest tensile strength and plasticity,and a new strengthening mechanism was achieved for the CoCrNiCu alloy.Moreover,twins were observed in the matrix phase after tensile fracture.Simultaneously,the dual-phase structure with different elastic moduli coordinated with each other during the deformation process,significantly improving the plasticity and strength of the CoCrNiCu alloy. 展开更多
关键词 Medium-entropy alloys Mechanical properties Laser directed energy deposition Misfit dislocations cu-rich phase
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微量Te对Cu-Cr-Zr合金组织及性能的影响
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作者 邓立勋 龚留奎 +5 位作者 尹飞 黄滢秋 张延松 陈子明 黄伟 张保元 《热加工工艺》 北大核心 2024年第8期128-134,共7页
采用SEM、EDS等微观表征以及显微硬度和导电性能检测手段,研究了Te含量对Cu-Cr-Zr-Te合金铸态组织及性能的影响。结果表明:随着Te含量的增加,铸态Cu-Cr-Zr-Te合金的硬度呈逐渐升高的的趋势,但导电性能基本趋于稳定状态,热锻处理后合金... 采用SEM、EDS等微观表征以及显微硬度和导电性能检测手段,研究了Te含量对Cu-Cr-Zr-Te合金铸态组织及性能的影响。结果表明:随着Te含量的增加,铸态Cu-Cr-Zr-Te合金的硬度呈逐渐升高的的趋势,但导电性能基本趋于稳定状态,热锻处理后合金的硬度和导电率都有所上升。铸态Cu-Cr-Zr-Te合金中低含量Te与Zr结合力较强易形成CuZrTe化合物,提升Te含量倾向于形成CuCrTe化合物;合金经900℃/4h的保温、热锻处理后,CuCrTe化合物分解为富Te相和富Cr相造成基体中Te元素的贫化,导致元素Te与元素Cr的相对比例减小而形成CuZrTe化合物。 展开更多
关键词 Cu-Cr-Zr-Te 硬度 CuZrTe化合物 CuCrTe化合物 富Cr相
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挤压铸造铝铜合金的组织与力学性能研究
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作者 邱小云 王冀恒 《铸造》 CAS 2024年第3期364-370,共7页
采用金相显微镜、扫描电镜和拉伸试验机等手段,研究了Mn/Fe比例和挤压压力对Al-Cu合金显微组织与力学性能的影响,揭示了Al-Cu合金中富铁相的存在形式和作用机理。结果表明,T6热处理态Al-Cu合金中存在针状β-Fe(Al_(7)Cu_(2)Fe)相和块状A... 采用金相显微镜、扫描电镜和拉伸试验机等手段,研究了Mn/Fe比例和挤压压力对Al-Cu合金显微组织与力学性能的影响,揭示了Al-Cu合金中富铁相的存在形式和作用机理。结果表明,T6热处理态Al-Cu合金中存在针状β-Fe(Al_(7)Cu_(2)Fe)相和块状Al_(7)Cu_(2)(FeMn)相;随着Mn/Fe比例的增加,Al-Cu合金中块状Al_(7)Cu_(2)(FeMn)相的体积分数逐渐增加,而针状β-Fe相的体积分数逐渐降低,在Mn/Fe比例为为1.2和1.5时合金中都为块状富铁相;相较于挤压压力为0的Al-Cu合金,在施加75 MPa挤压压力后,相同Mn/Fe比例的Al-Cu合金中的富铁相都更为细小和分散;当挤压压力为0时,Al-Cu合金在Mn/Fe比例为1.2时达到抗拉强度、屈服强度和断后伸长率的最大值;当挤压压力为25 MPa和75 MPa时,Al-Cu合金在Mn/Fe比例为0.9时取得抗拉强度和屈服强度最大值,而断后伸长率随着Mn/Fe比例增加而略有降低。 展开更多
关键词 AL-CU合金 挤压压力 T6热处理 富铁相 力学性能
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中非铜钴矿带钴矿成矿特征和富集机理
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作者 莫江平 胡乔帆 +3 位作者 方科 刘伟 周守余 李明君 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2024年第1期127-139,共13页
中非铜钴矿带是世界上规模大、铜钴品位高的层控型铜钴矿带,以拥有大型超大型铜钴矿床和众多的世界级铜钴矿山而闻名于世。本文综述了该成矿带的基本地质特征和矿化类型,分析了Co的超常富集机理,指出了存在的问题。中非铜钴矿带位于非... 中非铜钴矿带是世界上规模大、铜钴品位高的层控型铜钴矿带,以拥有大型超大型铜钴矿床和众多的世界级铜钴矿山而闻名于世。本文综述了该成矿带的基本地质特征和矿化类型,分析了Co的超常富集机理,指出了存在的问题。中非铜钴矿带位于非洲中南部的赞比亚和刚果(金)境内,全长700 km、宽150 km,包括赞比亚铜带省矿带、赞比亚西北省矿带和刚果(金)加丹加矿带。钴矿的形成经历了裂谷期成岩成矿作用(880~735 Ma)和造山期成矿作用(530~490 Ma),分别与新元古代加丹加沉积盆地的形成发展演化和卢富里安造山作用相对应。其成因类型包括同生沉积型钴矿床和热液改造型富钴矿床。沉积型钴矿在赞比亚境内发育,钴含量相对较低;热液改造型富钴矿床在刚果(金)境内更为发育,钴含量相对较高。钴与铜共生或伴生,主要含钴矿物为硫铜钴矿、方钴矿、硫钴矿、钴黄铁矿、水钴矿、钴华、菱钴矿等。Co的超常富集与由卤水在深部交代基底岩石(矿石)形成的富金属成矿流体通过迁移-富集-沉淀作用的多期次循环有关。矿床的氧化带、原生带分带明显,局部氧化深度达到300 m,表生氧化作用往往造成钴矿化富集。该区富钴矿床整体地质研究程度较低,原生铜钴矿的成矿物质来源、成矿环境特别是铜钴超常富集机理等方面的研究需要加强。 展开更多
关键词 富钴矿床 成矿特征 富集机理 中非铜钴矿带
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Genome-wide characterization of graft-transmissible mRNA-coding P450 genes of cucumber(Cucumis sativus L.) 被引量:1
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作者 Tao Wang Xiaohong Lu +6 位作者 Chenggang Xiang Xiaojun Li Wenqian Liu QingWang Zixi Liu Lihong Gao Wenna Zhang 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第2期250-260,共11页
P450(cytochrome P450)is a supergene family,which is involved in various metabolic pathways in plants.Based on previous study,we found some of cucumber P450 mRNAs were systemic mobile in cucumber/pumpkin grafts.However... P450(cytochrome P450)is a supergene family,which is involved in various metabolic pathways in plants.Based on previous study,we found some of cucumber P450 mRNAs were systemic mobile in cucumber/pumpkin grafts.However,the reason that why P450 mRNAs were endorsed as signaling,and what specific motif(s)did they harbored is not clear yet.Here,we first identified 221 CsaP450 genes in cucumber genomewide level.Combining with graft-transmissiblemRNAs datasets in cucumber,we elucidated 15mobile-CsaP450-coding genes,of which 5 and 10 belonged to A-type and non-A type respectively.Compared with Arabidopsis and pumpkin(Cucubit moschata)graft-induced-transmissible P450 mRNAs,a phylogenetic treewas constructed and divided into eight clans by usingmultiple-sequence alignment.Gene ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)annotations indicated that the expression patterns of the mobile-mRNA-coding CsaP450 genes in different tissues of cucumber was specifically enriched in oxidoreductase activity and secondary metabolic pathways.The structures and motifs of these 15 mobile-mRNA-coding CsaP450 genes and their types of regulatory elements told that the proportion of CU-rich motifs was higher than nonmobile-mRNA-coding CsaP450 genes.The integrated analysis of mobility direction and mRNA abundance of 15 mobilemRNA-coding CsaP450 genes allowed to conclude that there was rarely relationship between them.The study provided a new insight into the relationship between the motifs and functional characterization of mobile-mRNA-coding P450 genes of cucumber in genome-wide levels. 展开更多
关键词 Cucumis sativus GENOME-WIDE Cytochrome P450 mRNA mobility Phylogeny cu-rich motif
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Cu添加量对铸态CrFeCoNiCu_(x)高熵合金显微组织和力学性能的影响
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作者 胡强 王海玲 +3 位作者 钱立华 曾良才 王强 刘鑫旺 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第6期1803-1813,共11页
详细研究Cu添加量对铸态CrFeCoNi高熵合金显微组织演变和室温拉伸性能的影响。研究结果表明,添加Cu元素使高熵合金相结构由FCC单相转变为FCC1+FCC2双相。FCC2相是存在于枝晶间的富Cu相,且其体积分数随Cu含量的增加而提高。富Cu相的形成... 详细研究Cu添加量对铸态CrFeCoNi高熵合金显微组织演变和室温拉伸性能的影响。研究结果表明,添加Cu元素使高熵合金相结构由FCC单相转变为FCC1+FCC2双相。FCC2相是存在于枝晶间的富Cu相,且其体积分数随Cu含量的增加而提高。富Cu相的形成主要归因于Cu与其他金属元素的混合焓较大,从而导致凝固之前的液相分离。由于位错滑移的短程障碍增强,高熵合金的屈服强度和极限抗拉强度与Cu含量呈正相关关系。然而,由于位错在晶界堆积而产生的应力场叠加更为显著,因此,含Cu高熵合金的断裂应变较小。 展开更多
关键词 高熵合金 富Cu相 显微组织 抗拉强度 断裂应变
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相场法研究Al_(x)CuMnNiFe高熵合金富Cu相析出机理
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作者 王凯乐 杨文奎 +2 位作者 史新成 侯华 赵宇宏 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第7期313-327,共15页
BCC(体心立方)和FCC(面心立方)结构共存的高熵合金通常具有优异的综合力学性能,Al元素可以促进含Cu高熵合金由FCC向BCC结构转变.本文基于Chan-Hilliard方程和Allen-Cahn方程,建立Al_(x)CuMnNiFe高熵合金三维相场模型,模拟了Al_(x)CuMnN... BCC(体心立方)和FCC(面心立方)结构共存的高熵合金通常具有优异的综合力学性能,Al元素可以促进含Cu高熵合金由FCC向BCC结构转变.本文基于Chan-Hilliard方程和Allen-Cahn方程,建立Al_(x)CuMnNiFe高熵合金三维相场模型,模拟了Al_(x)CuMnNiFe高熵合金(x=0.4,0.5,0.6,0.7)在823 K等温时效时纳米富Cu相的微观演化过程.结果表明,Al_(x)CuMnNiFe高熵合金时效时会产生两种复杂核壳结构:富Cu核/B2_(s)壳以及B2_(c)核/FeMn壳,通过讨论分析发现形成的B2_(c)对纳米富Cu相的形成起到抑制作用,这种抑制作用随着Al元素的增加而变大;结合经验公式做出Al_(x)CuMnNiFe高熵合金富Cu相的屈服强度随时效时间的变化曲线,得到峰值屈服强度的时效时间和合金体系,可以为时效工艺提供参考. 展开更多
关键词 相场法 高熵合金 富Cu相 弹性能
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