Anomalies in Hall-Petch strengthening for nanocrystalline Au–Cu alloys below 10nm grain size

2010 ◽  
Vol 205 (5) ◽  
pp. 1398-1402 ◽  
Author(s):  
Alan F. Jankowski ◽  
Luke O. Nyakiti
Keyword(s):  
Grain Size ◽  
Cu Alloys

Thermal decomposition of mechanically alloyed nanocrystalline fcc Fe60Cu40

1996 ◽  
Vol 11 (11) ◽  
pp. 2717-2724 ◽  
Author(s):  
J. Y. Huang ◽  
Y. D. Yu ◽  
Y. K. Wu ◽  
H. Q. Ye ◽  
Z. F. Dong
Keyword(s):  
Solid Solution ◽  
Grain Size ◽  
Magnetic Measurement ◽  
Orientation Relationships ◽  
Maximum Solubility ◽  
Mechanically Alloyed ◽  
X Ray ◽  
Cu Content ◽  
Cu Alloys ◽  
Transmission Electron

A ferromagnetic and supersaturated fcc Fe60Cu40 solid solution was prepared by mechanical alloying (MA). The phase transformations of the as-milled Fe60Cu40 powder upon heating to 1400 °C and subsequently cooling to room temperature were characterized by differential thermal analysis (DTA) and thermal magnetic measurement. The fcc Fe60Cu40 solid solution decomposes into α–Fe(Cu) + γ–Fe(Cu) + Cu(Fe) upon heating from 300 to 460 °C, and on further heating, α–Fe(Cu) transforms to γ–Fe(Cu) at 640 → 760 °C; during cooling, the reverse transformation occurs from 800 → 640 °C (obtained from thermomagnetic measurement) or from 700 → 622 °C (obtained from DTA). The γ ⇆ α transformation in mechanically alloyed Fe60Cu40 nanocrystalline occurs in a wide temperature range; the transformation temperature is higher than that of the martensite transformation in as-cast Fe–Cu alloys, but is much lower than that of the allotropic transformation of pure Fe. These differences may be caused by the different fabrication process, the nonequilibrium microstructure of MA, as well as the inhomogeneous grain size in α–Fe(Cu). High resolution transmission electron microscope (HRTEM) observations carried out in the specimen after the DTA run show that N-W or K-S orientation relationships exist between α–Fe(Cu) and Cu(Fe), which also represent the orientation relationship between α–Fe(Cu) and γ–Fe(Cu) due to excellent coherency between γ–Fe(Cu) and Cu(Fe). The grain size of the α–Fe(Cu) is inhomogeneous and varies from 50–600 mm. Energy dispersive x-ray spectroscopy (EDXS) result shows that the Cu content in these α–Fe(Cu) grains reaches as high as 9.5 at. % even after DTA heating to 1400 °C, which is even higher than the maximum solubility of Cu in γ–Fe above 1094 °C. This may be caused by the small grain size of α–Fe(Cu).

Texture of Al-Cu Alloys Deformed by ECAP

2005 ◽  
Vol 495-497 ◽  
pp. 851-856 ◽  
Author(s):  
Jan Kuśnierz ◽  
Marie Helene Mathon ◽  
Thierry Baudin ◽  
Zdzislaw Jasieński ◽  
Richard Penelle
Keyword(s):  
Grain Size ◽  
Aluminium Alloys ◽  
Superplastic Forming ◽  
Orientation Distribution ◽  
Coarse Grained ◽  
Fine Grained ◽  
Angular Pressing ◽  
Cu Alloys ◽  
Super Plastic ◽  
Short Time

Materials of ultra-fine grained microstructure (sub-micrometer grain size) exhibit large strength, hardness and ductility and also the increased toughness in comparison with conventional coarse-grained ones. In these materials also the super-plastic flow at lower temperatures is observed. This behaviour may be interesting when aluminium alloys like AlCuZr, used in superplastic forming, are considered. In the paper, the methods of preparing such materials by equal-channel angular pressing (ECAP) is proposed and the texture analysis, based on neutron diffraction pole figure measurements and calculated orientation distribution function of two alloys AlCu4SiMn and AlCu5AgMgZr is discussed. The influence of short time recrystallization is discussed in relation with TEM and SEM observations.

Ultrahigh Purity Copper Alloy Target Used Innanoscale ULSI Interconnects

2015 ◽  
Vol 815 ◽  
pp. 22-29
Author(s):  
Hao Zeng ◽  
Chao Lv ◽  
Yan Gao ◽  
Ting Yi Dong ◽  
Yong Hui Wang ◽  
...  
Keyword(s):  
Grain Size ◽  
Copper Alloy ◽  
Alloy Composition ◽  
Critical Dimension ◽  
Promising Technique ◽  
Large Size ◽  
Cu Alloys ◽  
Alloy Target ◽  
Deposited Film ◽  
Purity Copper

Current ULSI circuits have features with dimensions in the nanoscale region. As the critical dimension shrinks, Cu BEOL systems face reliability impacts. Alloying has been proved to be a promising technique to retard grain boundary electro-migration (EM). In this paper, dilute Cu Alloys such as Cu-Al, Cu-Mn for dual-damascene interconnect applications have been investigated. The alloy chosen principle for nanoscale interconnects has been discussed. The ultrahigh purity copper alloy target properties including purity, alloy composition, grain size and sputtering performance were investigated, to lay the foundation for the application of the large-size ultrahigh purity copper alloy target used for 300mm wafer fabrication. The relationships between deposited film behaviors and sputtering target properties in some applications were also discussed. In order to acquire high quality thin film, the properties of sputtering target such as alloy composition homogeneity, grain size and uniformity et al. have to be well controlled by proper fabrication techniques.

scholarly journals Numerical and Experimental Investigation of the Influence of Growth Restriction on Grain Size in Binary Cu Alloys

Metals ◽  
2017 ◽  
Vol 7 (9) ◽  
pp. 383 ◽  
Author(s):  
Andreas Cziegler ◽  
Olga Geraseva ◽  
Peter Schumacher
Keyword(s):  
Experimental Investigation ◽  
Grain Size ◽  
Growth Restriction ◽  
Cu Alloys

Effect of Hot-Extrusion Conditions on Mechanical Properties and Microstructure of P/M Al-Zn-Mg-Cu Alloys Containing Zr

2006 ◽  
Vol 519-521 ◽  
pp. 1479-1484 ◽  
Author(s):  
Hiroki Adachi ◽  
Kozo Osamura ◽  
Jun Kusui ◽  
Shigeru Okaniwa
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Tensile Strength ◽  
Solution Treatment ◽  
Hot Extrusion ◽  
Extrusion Ratio ◽  
Grain Coarsening ◽  
Extrusion Rate ◽  
Cu Alloys ◽  
Zr Alloys

The effect of extrusion rate and ratio on the Al3Zr induced dynamic recrystallization (DRX) that occurs during hot extrusion of RS-P/M Al-Zn-Mg-Cu-Zr alloys was investigated. An increase in the logarithm of extrusion rate promoted DRX and lead to a monotonic increase in the number of fine grains. Although DRX was also promoted and the grain size reduced by an increase in extrusion ratio from 10 to 20, the DRX behavior hardly changed, even when the extrusion ratio exceeded 20. However, with increasing extrusion ratio, the width of fibrous grain, i.e., the unrecrystallized region, decreased and the tensile strength increased to 879 MPa. When the extrusion rate and ratio exceeded 54 mm/min and 20, respectively, a marked grain coarsening occurred upon solution treatment, and the tensile strength tended to decrease, because of the high dislocation density induced by hot extrusion. By annealing at 563 K before solution treatment, it was possible to prevent grain coarsening, and thus prevent the strength decrease.

Reversible grain size changes in ball-milled nanocrystalline Fe–Cu alloys

1992 ◽  
Vol 7 (8) ◽  
pp. 1980-1983 ◽  
Author(s):  
J. Eckert ◽  
J.C. Holzer ◽  
C.E. Krill ◽  
W.L. Johnson
Keyword(s):  
Grain Size ◽  
Mechanical Alloying ◽  
Single Phase ◽  
Underlying Mechanism ◽  
Solution Hardening ◽  
Cu Alloys ◽  
Average Grain Size ◽  
20 Nm ◽  
Composition Changes ◽  
Fcc Structure

Nanocrystalline FexCu100−x solid solutions (x < 60) with single-phase fcc structure have been prepared by mechanical alloying. The average grain size of the powders (8–20 nm) depends on the composition of the material. Varying the composition changes the grain size reversibly. This can be explained by the underlying mechanism of plastic deformation and solution hardening during mechanical alloying coupled with the recovery behavior of the material.

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