含稀土Cu-Cr-Zr合金的微观组织和性能（英文）

先后热轧、固溶处理、冷轧和时效处理Cu-0.81Cr-0.12Zr-0.05La-0.05Y(质量分数)合金,并系统研究其不同阶段的微观结构、显微硬度和导电率的变化规律。合金铸态组织由Cu基体、Cr相和Cu5Zr三相组成。经固溶处理后,Zr相充分溶于Cu基体中,而部分Cr相仍残留于Cu基体中。样品冷轧后的时效处理使Cr与Cu5Zr纳米析出相从基体中析出,且基体显微硬度和导电率增加。在773 K时效60 min后,样品获得了高显微硬度(HV 186)和高导电率(81%IACS)。随着时效温度的提高,Cu晶体的取向度逐渐减小到零,而微应变因存在析出相和位错的相互作用未能得到完全的释放。当共格强化机制在合金中起主要增强作用时,Cr析出相与铜基体之间保持着N-W的位相关系。     

高压时效处理对Cu-51.15W-0.24Cr合金组织和性能的影响

针对Cu-W合金的强度和导热导电性偏低问题，对Cu48.61W51.15Cr0.24合金进行了高压时效处理，并对比了高压时效处理和常压时效处理后合金的微观组织，硬度，热导率以及导电率。结果表明：高压时效处理能增大Cu48.61W51.15Cr0.24合金的致密度，使组织中析出的Cr相更加弥散细小，改善合金的硬度及导热导电性能。该合金经960 ℃/1 h固溶后，再在3 GPa压力下500 ℃时效1 h处理可获得较高的硬度、热扩散系数及较低的电阻率，其值分别为1540 MPa、0.5236 cm²·s^-1和4.458×10^-8 Ω·m，较相同工艺常压时效处理后的硬度和热扩散系数分别增加了17.56%和10.74%，而电阻率却降低了4.85%。因此，高压时效处理是提高Cu-51.15W-0.24Cr合金力学性能、降低电阻率的有效途径。     

粉末冶金Cu-Zr合金的微结构及性能研究

采用高纯、高速N2(99.999%)流作为介质淬火处理在真空下固溶的粉末冶金Cu-Zr合金,然后时效处理.用HV、HB、XRD、TEM、SEM、EDS等来表征不同状态下的合金组织性能.结果表明:随着固溶时间的增加,合金的布氏硬度(HB)和导电率减小,而显微硬度(HV)增加:铜锆合金时效析出Cu2Zr,时效处理时间小于12 h时,合金的HB和导电率增加而HV减小,时效处理时间大于12 h时,合金的HB和HV减小而导电率增加,沉淀相长大.     

Cr含量对Cu-Cr-Zr-Y合金时效性能的影响

对两种不同Cr含量的合金Cu-0．43Cr-0．058Zr-0．031Y和Cu-0．20Cr-0．066Zr-0．060Y，在900—980℃进行了固溶处理，并对显微硬度和电导率进行了测试，对固溶态金相组织进行了观察。结果表明，Cr含量较高的Cu-0．43Cr-0．058Zr-0．031Y合金的固溶处理温度可采用960℃，而Cr含量较低的Cu-0．20Cr-0．066Zr-0．060Y合金为920℃。两种合金固溶后分别在400—520℃进行时效，其电导率和显微硬度的测试对比结果表明，Cr含量较高的合金在较低温度（400℃）时效后的电导率比Cr含量较低合金的低，而较高温度（480℃）时效后Cr含量对电导率的影响不明显；Cr含量对合金显微硬度的影响较大，不同时效温度处理后，Cr含量高的合金硬度均明显低于低Cr含量合金。     

Cu-Cr合金强化机制研究及其对导电性能的影响

采用真空铸造-固溶处理-冷轧-时效处理工艺制备了Cu-0．8％Cr合金。利用金相显微镜、透射电镜、选取电子衍射、硬度和电导率测试等手段考察了合金在不同处理状态下的组织和性能，定量分析了不同强化方式对合金硬度及导电性能的影响。结果表明：与固溶强化相比，析出强化方法更能有效强化合金，对导电性能影响也更小；形变强化能显著提高合金硬度，但对导电性能几乎无影响；大预变形、短时时效是合金获得较高综合性能的有效手段。     

固溶温度对Cu-Cr-Zr-RE合金性能和组织的影响

通过对Cu-0.43Cr-0.58Zr-0.031Y合金和Cu-0.20Cr-0.66Zr-0.060Y合金进行不同温度固溶处理后合金硬度和导电率的测定与分析,可以确定Cu-0.43Cr-0.67Zr-0.031Y合金的固溶温度为960℃,Cu-0.20Cr-0.63Zr-0.060Y合金为920℃.运用金相和扫描电镜对固溶后合金的显微组织进行观察和分析,发现Cr是影响固溶温度的主要因素,合金的固溶温度随Cr含量的增加而升高.     

Cu-Cr-Zr-Ce-Y合金时效析出特性和受电磨损行为研究

对Cu-Cr-Zr—Ce—Y合金时效析出特性、受电滑动磨损形貌及电磨损机理进行研究。结果表明：Cu-0．34Cr-0．06Zr-0．03Ce-0．03Y合金在950℃固溶1h后,在480℃时效处理能获得较高的显微硬度和导电率。时效前冷变形能大大加快析出相的析出,析出相对位错的钉扎作用强烈阻碍合金再结晶的形核和长大,使合金产生明显的时效硬化。固溶合金经60％冷变形后在480℃时效2h,其显微硬度和导电率分别高达163HV和79．78％IACS,而固溶后直接时效时仅为119HV和68．25％IACS。受电磨损时,合金的磨损量随加载电流的提高而增加,其主要磨损机制为粘着磨损、磨粒磨损及电蚀磨损。     

变形量对接触线用Cu-Cr-Zr-Y合金时效特性和力学性能的影响

探讨了不同变形量对电气化铁路接触线用Cu-0．42Cr-0．13Zr-0．11Y合金时效性能和力学性能的影响。研究结果表明，合金经950℃、1h固溶处理后施以不同程度冷变形，再进行480℃时效处理，比合金固溶后直接时效可显著提高合金的电导率和显微硬度；随变形量逐渐增大，合金强度不断升高，抗拉强度最高可达645MPa，而延伸率和导电率略有降低。当二次拉拔变形量为75．0％时，合金的抗拉强度、导电率和延伸率分别为605．6MPa、80．79％IACS和10．2％。     

固溶时效对Al-0.2Ni铝合金组织和性能的影响

通过硬度和导电率测量并采用金相显微镜、扫描电镜等分析技术,研究了不同固溶时效处理对Al-0.2Ni铝合金的组织和性能的影响。结果表明:Al-0.2Ni铝合金经600℃×12 h固溶+250℃×10 h时效处理后的组织和硬度最好,在此工艺处理下,Al-0.2Ni合金的硬度和导电率分别是30.883 HV、62.16%IACS。在固溶处理时,粗大的含Ni初生相大部分回溶,晶粒未发生粗化。固溶后200~400℃时效处理,合金的硬度峰值随着时效温度的增高而先升后降,在250℃时效时,随着时效时间的延长,Al-0.2Ni合金的硬度先增后减,而导电率略有升高。     

固溶时效对Cu-1.4Ni-1.2Co-0.6Si合金组织性能的影响

研究了不同固溶工艺条件对Cu-1.4Ni-1.2Co-0.6Si合金显微组织的影响,对合金固溶-时效后的显微硬度和导电率进行了分析,并采用电子衍射及透射电镜分析其显微组织。结果表明:合金铸态组织以等轴晶为主,热轧变形组织中存在许多细小析出相。热轧合金在固溶处理过程中基体变形组织发生再结晶和晶粒长大,且随着固溶温度升高,析出相固溶量增加,至975℃时,析出相粒子基本回溶到基体中。合金中的析出相与Cu-Ni-Si合金具有相同的结构和形貌,与Cu基体的位向关系为:[001]Cu//[110]p,(010)Cu//(001)p;[112]Cu//[32 4]p,(110)Cu//(2 11)p。合金最佳固溶-时效处理工艺为975℃×1.5 h+500℃×4 h时效,在此工艺条件下,合金显微硬度为232 HV,相对导电率为49%IACS。     

Zr、Cr元素对Al-Si合金电导率与力学性能的影响

通过正交试验和验证试验研究了不同的Si、Zr、Cr元素含量对Al-Si合金电导率与力学性能的影响.结果表明:当合金的成分为5%Si、0.35%Zr、0.35%Cr、1%Cu、0.5%Mg,经过T6处理后,电导率达到25.35 MS/m,抗拉强度达到361 MPa,伸长率达到2.83%,布氏硬度为109.34,均超越ZL101A.合金中的Si在改善合金力学性能的同时直接减少Al基体的有效导电截面,使合金的电导率下降;微量Zr可以在几乎不影响电导率的情况下提高合金力学性能;Cr元素对合金起到一定的强化作用.通过试验可将Al-Si合金的电导率提高5%～8%.     

Effect of V addition on hardness and electrical conductivity in Cu-Ni-Si alloys

The effect of vanadium (V) addition on the microstructure, the hardness and the electrical conductivity of Cu-2.8Ni-0.7Si alloys was investigated. The V-free, the 0.1 wt% V-added, the 0.2 wt% V-added Cu base alloys were exposed to the same experimental conditions. After the cold rolling of the studied alloys, the matrix was recrystallized during the solution heat treatment at 950 °C for 2 h. However, small amounts of vanadium substantially suppressed the recrystallization and retarded the grain growth of the Cu base alloys. The added vanadium accelerated the precipitation of Ni₂Si intermetallic compounds during aging and therefore it contributed positively to the resultant hardness and electrical conductivity. It was found that the hardness and the electrical conductivity increased simultaneously with increasing aging temperature and time with accelerated precipitation kinetics by the addition of vanadium. In the present study, the Cu-2.8Ni-0.7Si alloy with 0.1 wt%V was found to have an excellent combination of the hardness and the electrical conductivity when it was aged at 500 °C.     

镁与热处理对Al-4Si-(xMg)合金导电性及力学性能的影响

利用SEM、XRD、EDS、硬度计及电阻率测试仪等方法分析Mg元素和不同热处理对Al-4Si-(xMg)(x=0～1.5％,质量分数)系列合金导电率及硬度的影响.结果表明:随Mg添加量增加,铸态合金的导电率和硬度先增后减,最佳添加量为1.1％.Mg使铸态合金硬度显著增加,但恶化了其导电率.Al-4Si-(xMg)合金经...     

石墨烯对Gr/CuCr10复合材料显微组织和性能的影响

采用热压烧结工艺制备石墨烯含量分别为0.1％、0.3％、0.5％和0.7％(质量分数)的Gr/CuCr10合金.与CuCr10合金相比,石墨烯添加量为0.3％(质量分数)的CuCr10复合材料相对密度保持不变,而电导率从62.2％(IACS)增加到69.5％(IACS).导电率增加的主要原因是石墨烯的加入导致Cr相尺寸...     

Effect of roll-bonding temperature on the strength and electrical conductivity of an α-brass-clad Cu–1Cr alloy composite

Tri-layered α-brass-clad Cu–Cr-alloy composite plates were prepared by hot roll-bonding. Neither intermetallic-compound layers nor interface defects were observed at the interfaces in the as-rolled and heat-treated α-brass-clad Cu–Cr composite plates. The hardness of the as-rolled α-brass layer was greater than that of the Cu–Cr substrate, since the α-brass was strengthened by strain hardening more efficiently upon rolling. The hardness of the α-brass decreased appreciably upon annealing because of the recovery processes, whereas that of the Cu–Cr layer slightly increased after heat treatment at 450°C due to the precipitation strengthening. After the post-roll-bonding heat treatment at 450°C, the strength of the α-brass-clad Cu–Cr-alloy composite decreased with a significant increase in ductility. The electrical conductivity of the asroll-bonded α-brass clad Cu–Cr alloy composite (47–52% IACS) increased significantly (to 72–74% IACS) after the 1-h heat treatment. The strength and conductivity of the clad composite are dependent on the precipitation strengthening of Cu–Cr and recovery softening of α-brass in the course of the post-roll-bonding heat treatment.     

Influence of Fe addition on microstructure and properties of Cu-Ag composite

We investigated the effects of Fe content on microstructure and properties in as-cast and as-drawn Cu-(5.1-x) vol%Ag-x vol%Fe alloys. In microscale, increasing Fe content first refined and then coarsened Cu dendrites. In nanoscale, the size and length of Ag precipitates in Fe-doped alloys were smaller than the size and length of Ag precipitates in Fe-free alloy, and the γ-Fe precipitates in Cu-2.9 vol%Ag-2.4 vol%Fe alloy were finer than the γ-Fe precipitates in Cu-5.1 vol%Fe alloy. The maximum hardness in as-cast Cu-Ag-Fe alloys was found in the Cu-2.9 vol%Ag-2.4 vol%Fe alloy. With increasing drawing strain, both ultimate tensile strength and hardness of Cu-Ag-Fe composites were increased. Simulation data among the relative volume fractions of Fe, hardness and electrical conductivity showed that, as the relative value approached 40%, the Cu-Ag-Fe composite displayed greater hardness than other samples. As a small amount of Ag was replaced by Fe, the electrical conductivity decreased significantly with a descending slope of approximately 3%IACS (International Annealed Copper Standard) per vol% Fe. As 47 vol%Ag was replaced by Fe, however, the electrical conductivity decreased by 51% and remained almost invariable with further increasing Fe content. After annealing at 450 °C for 4 h, the electrical conductivity of the Cu-2.9 vol%Ag-2.4 vol%Fe composite was elevated up to 68.3%IACS from 38.5%IACS.     

热处理工艺对ITER级CuCrZr合金性能的影响

研究了同溶温度、时效温度和时间对ITER级Cu-0.8Cr-0.1Zr合金强化规律的影响和不同工艺下的金相组织,分析了合金导电率随时效温度的变化规律.结果表明:Cu-0.8Cr-0.1Zr合金硬度均随同溶温度、时效温度和时间的增加而呈现出峰值.在950℃同溶、480℃时效3 h后获得最佳硬化效果,硬度值为138 HV0.2.合金经同溶处理后的相对导电率仅为34%IACS,随时效温度的升高,导电率增加,480℃时效处理3 h,导电率达最大值74%IACS.     

扩展路径低温ECAP及时效热处理对Cu0.6Cr合金的组织和性能影响

采用光学显微镜和X射线衍射仪对Cu0.6Cr合金经低温扩展路径等通道转角挤压（ECAP）后的组织演变规律进行了研究。采用扫描电子显微镜和能谱仪研究了Cu0.6Cr合金经不同时效热处理条件后的晶粒大小、析出相分布规律和断裂特征。并且分别测试了合金经低温ECAP和低温ECAP+时效热处理后的抗拉伸强度、硬度和导电率。结果表明,Cu0.6Cr合金经低温ECAP变形后形成明显细化且相互交割的纤维组织,并且合金在变形中始终保持（111）面的择优取向。时效热处理的合金变形量越大,析出相的数目和尺寸就越大,第二相析出速率也越快。5道次合金经450 ℃时效2 h后的抗拉伸强度为568.1 MPa,维氏硬度为1624.8 MPa,导电率为82%IACS。     

Effect of cryorolling on microstructure and property of high strength and high conductivity Cu−0.5wt.%Cr alloy

Cu−0.5wt.%Cr alloy with high strength and high conductivity was processed by cryorolling (CR) and room temperature rolling (RTR), respectively. The microstructure, mechanical property and electrical conductivity of Cu−0.5Cr alloy after CR/RTR and aging treatment were investigated. The results indicate that obvious dislocation entanglement can be observed in matrix of CR alloy. The Cr particles in the alloy after CR and aging treatment possess finer particle size and exhibit dispersive distribution. The peak hardness of CR alloy is HV 167.4, significantly higher than that of RTR alloy. The optimum mechanical property of CR alloy is obtained after aging at 450 °C for 120 min. The conductivity of CR Cu−0.5Cr alloy reaches 92.5% IACS after aging at 450 °C for 120 min, which is slightly higher than that of RTR alloy.