Wear and friction properties of surface modified Cu nanoparticles as 50CC oil additive were studied. The effect of temperature on tribological properties of Cu nanoparticles was investigated on a four-ball tester. The...Wear and friction properties of surface modified Cu nanoparticles as 50CC oil additive were studied. The effect of temperature on tribological properties of Cu nanoparticles was investigated on a four-ball tester. The morphologies, typical element distribution and chemical states of the worn surfaces were characterized by SEM, EDS and XPS, respectively. In order to further investigate the tribological mechanism of Cu nanoparticles, a nano-indentation tester was utilized to measure the micro mechanical properties of the worn surface. The results indicate that the higher the oil temperature applied, the better the tribological properties of Cu nanoparticles are. It can be inferred that a thin copper protective film with lower elastic modulus and hardness is formed on the worn surface, which results in the good tribological performances of Cu nanoparticles, especially when the oil temperature is higher.展开更多
目的制备15 nm的(AlCrTaTiZrMo)N六元高熵合金氮化物薄膜,并对其扩散阻挡性能进行表征。方法使用直流磁控溅射设备在单晶硅上沉积(Al Cr Ta Ti Zr Mo)N高熵合金氮化物薄膜,然后在薄膜上沉积150 nm的Cu,形成Cu/(AlCrTaTiZrMo)N/Si结构。...目的制备15 nm的(AlCrTaTiZrMo)N六元高熵合金氮化物薄膜,并对其扩散阻挡性能进行表征。方法使用直流磁控溅射设备在单晶硅上沉积(Al Cr Ta Ti Zr Mo)N高熵合金氮化物薄膜,然后在薄膜上沉积150 nm的Cu,形成Cu/(AlCrTaTiZrMo)N/Si结构。在600℃下,对该结构进行不同时间的退火处理,使用X射线衍射仪(XRD)、四探针测试仪(FPP)、原子力显微镜(AFM)和场发射扫描电子显微镜(FESEM)研究薄膜成分及退火时间对薄膜组织结构、表面形貌、方块电阻的影响,研究其扩散阻挡性。结果高熵合金氮化物薄膜与基体Si和Cu的结合性较好。沉积态高熵合金氮化物薄膜为非晶结构,表面光滑平整,方块电阻阻值较低。在600℃下经1h退火后,薄膜仍为非晶结构,表面发生粗化。随着退火时间增加,5h退火后,结构中出现少量纳米晶,大部分仍为非晶,表面粗糙度增加。退火7 h后,结构没有发生变化,仍为非晶包裹纳米晶结构,Cu表面生成部分岛状物,方块电阻阻值仍然较低,且无Cu-Si化合物生成,证明(AlCrTaTiZrMo)N高熵合金氮化物薄膜在长时间退火处理后,仍能保持良好的铜扩散阻挡性。结论 15nm的(AlCrTaTiZrMo)N高熵合金氮化物薄膜在600℃下退火7h后,其非晶包裹纳米晶的结构能有效阻挡Cu的扩散,表现出了优异的热稳定性与扩散阻挡性。展开更多
Potentiodynamic polarisation, potential-time measurements, X-ray diffraction (XRD) and infrared spectroscopy (IR) have been used to investigate the effect of different concentrations of Na2SO4 in the absence and prese...Potentiodynamic polarisation, potential-time measurements, X-ray diffraction (XRD) and infrared spectroscopy (IR) have been used to investigate the effect of different concentrations of Na2SO4 in the absence and presence of NaCI, on the corrosion of Cu-alloy. The electrochemical measurements showed that the increase of Na2SO4 concentration led to increase the corrosion current density of Cu alloy and vice versa. The presence of NaCI shifted the potential to more cathodic potential, which had a great influence on the protectiveness of the Cu oxide layer formed on the surface in presence of Na2SO4. The spectrometric measurements indicated the constituents of the film formed on the alloy surface were mainly Cu2O, in addition to the oxides, NiO and Fe2O3, which were traced by XRD analysis.展开更多
Cu films with thickness of 630-1300nm were deposited on glass substrates without heating by DC magnetron sputtering in pure Ar gas. Ar pressure was controlled to 0.5, 1.0 and 1.5Pa respectively. The target voltage was...Cu films with thickness of 630-1300nm were deposited on glass substrates without heating by DC magnetron sputtering in pure Ar gas. Ar pressure was controlled to 0.5, 1.0 and 1.5Pa respectively. The target voltage was fixed at 500V but the target current increased from 200 to 1150mA with Ar pressure increasing. X-ray diffraction, scanning electron microscopy and atomic force microscopy were used to observe the structural characterization of the films. The resistivity of the films was measured using four-point probe technique. At all the Ar pressures, the Cu films have mixture crystalline orientations of [111], [200] and [220] in the direction of the film growth. The film deposited at lower pressure shows more [111] orientation while that deposited at higher pressure has more [220] orientation. The amount of larger grains in the film prepared at 0.5Pa Ar pressure is slightly less than that prepared at 1.0Pa and 1.5Pa Ar pressures. The resistivities of the films prepared at three different Ar pressures represent few differences, about 3-4 times of that of bulk material. Besides the deposition rate increases with Ar pressure because of the increase in target current. The contribution of the bombardment of energetic reflected Argon atoms to these phenomena is discussed.展开更多
基金Project(2007CB607601) supported by the National Basic Research Program of ChinaProject(50735006) supported by the National Natural Science Foundation of China+1 种基金Project(9140C8502010702) supported by the National Key Laboratory for Remanufacturing FoundationProject(9140A27030206OC8501) supported by the Key Program for Pre-research of Chinese Government
文摘Wear and friction properties of surface modified Cu nanoparticles as 50CC oil additive were studied. The effect of temperature on tribological properties of Cu nanoparticles was investigated on a four-ball tester. The morphologies, typical element distribution and chemical states of the worn surfaces were characterized by SEM, EDS and XPS, respectively. In order to further investigate the tribological mechanism of Cu nanoparticles, a nano-indentation tester was utilized to measure the micro mechanical properties of the worn surface. The results indicate that the higher the oil temperature applied, the better the tribological properties of Cu nanoparticles are. It can be inferred that a thin copper protective film with lower elastic modulus and hardness is formed on the worn surface, which results in the good tribological performances of Cu nanoparticles, especially when the oil temperature is higher.
文摘目的制备15 nm的(AlCrTaTiZrMo)N六元高熵合金氮化物薄膜,并对其扩散阻挡性能进行表征。方法使用直流磁控溅射设备在单晶硅上沉积(Al Cr Ta Ti Zr Mo)N高熵合金氮化物薄膜,然后在薄膜上沉积150 nm的Cu,形成Cu/(AlCrTaTiZrMo)N/Si结构。在600℃下,对该结构进行不同时间的退火处理,使用X射线衍射仪(XRD)、四探针测试仪(FPP)、原子力显微镜(AFM)和场发射扫描电子显微镜(FESEM)研究薄膜成分及退火时间对薄膜组织结构、表面形貌、方块电阻的影响,研究其扩散阻挡性。结果高熵合金氮化物薄膜与基体Si和Cu的结合性较好。沉积态高熵合金氮化物薄膜为非晶结构,表面光滑平整,方块电阻阻值较低。在600℃下经1h退火后,薄膜仍为非晶结构,表面发生粗化。随着退火时间增加,5h退火后,结构中出现少量纳米晶,大部分仍为非晶,表面粗糙度增加。退火7 h后,结构没有发生变化,仍为非晶包裹纳米晶结构,Cu表面生成部分岛状物,方块电阻阻值仍然较低,且无Cu-Si化合物生成,证明(AlCrTaTiZrMo)N高熵合金氮化物薄膜在长时间退火处理后,仍能保持良好的铜扩散阻挡性。结论 15nm的(AlCrTaTiZrMo)N高熵合金氮化物薄膜在600℃下退火7h后,其非晶包裹纳米晶的结构能有效阻挡Cu的扩散,表现出了优异的热稳定性与扩散阻挡性。
文摘Potentiodynamic polarisation, potential-time measurements, X-ray diffraction (XRD) and infrared spectroscopy (IR) have been used to investigate the effect of different concentrations of Na2SO4 in the absence and presence of NaCI, on the corrosion of Cu-alloy. The electrochemical measurements showed that the increase of Na2SO4 concentration led to increase the corrosion current density of Cu alloy and vice versa. The presence of NaCI shifted the potential to more cathodic potential, which had a great influence on the protectiveness of the Cu oxide layer formed on the surface in presence of Na2SO4. The spectrometric measurements indicated the constituents of the film formed on the alloy surface were mainly Cu2O, in addition to the oxides, NiO and Fe2O3, which were traced by XRD analysis.
基金The authors would like to thank Prof. Y.B. Wang and Mr. S. Liang of the Department of Material Physics for supporting AFM observations. The authors also would like to thank Ms. J.P. He of the State Key Laboratory for Advanced Metals and Materials for sup
文摘Cu films with thickness of 630-1300nm were deposited on glass substrates without heating by DC magnetron sputtering in pure Ar gas. Ar pressure was controlled to 0.5, 1.0 and 1.5Pa respectively. The target voltage was fixed at 500V but the target current increased from 200 to 1150mA with Ar pressure increasing. X-ray diffraction, scanning electron microscopy and atomic force microscopy were used to observe the structural characterization of the films. The resistivity of the films was measured using four-point probe technique. At all the Ar pressures, the Cu films have mixture crystalline orientations of [111], [200] and [220] in the direction of the film growth. The film deposited at lower pressure shows more [111] orientation while that deposited at higher pressure has more [220] orientation. The amount of larger grains in the film prepared at 0.5Pa Ar pressure is slightly less than that prepared at 1.0Pa and 1.5Pa Ar pressures. The resistivities of the films prepared at three different Ar pressures represent few differences, about 3-4 times of that of bulk material. Besides the deposition rate increases with Ar pressure because of the increase in target current. The contribution of the bombardment of energetic reflected Argon atoms to these phenomena is discussed.
