Interfacial reactions and matrix microstructure evolution in SiCf/Ti composites dominated by primary structure of Ti matrix

2019 ◽  
Vol 45 (14) ◽  
pp. 17767-17774 ◽  
Author(s):  
Shuming Zhang ◽  
Minjuan Wang ◽  
Mao Wen ◽  
Ming Wu ◽  
Qingfeng Wang ◽  
...  
Metals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 481 ◽  
Author(s):  
Zhang ◽  
Lian ◽  
Chen ◽  
Sun ◽  
Zhang ◽  
...  

The hot deformation behavior and microstructure evolution of a 7.5 vol% TiBw/near α-Ti composite with fine matrix microstructure were investigated under the deformation conditions in a temperature range of 800–950 °C and strain rate range of 0.001–1 s−1 using plane strain compression tests. The flow stress curves show different characteristics according to the various deformation conditions. At a higher strain rate (1 s−1), the flow stress of the composite continuously increases until a peak value is reached. The activation energy is 410.40 kJ/mol, much lower than the activation energy of as-sintered or as-forged composites. The decreased activation energy is ascribed to the breaking of the TiBw reinforcement during the multi-directional forging and the resultant fine matrix microstructure. Refined reinforcement and refined matrix microstructure significantly improve the hot deformation ability of the composite. The deformation conditions determine the morphology and fraction of α and β phases. At 800–900 °C and 0.01 s−1 the matrix α grains are much refined due to the continuous dynamic recrystallization (CDRX). The processing map is constructed based on the hot deformation behavior and microstructure evolution. The optimal hot processing window is determined to be 800–950 °C/0.001–0.01 s−1, which lead to CDRX of primary α grains or dynamic recovery (DRV) and dynamic recrystallization (DRX) of β phase.


2021 ◽  
pp. 2100221
Author(s):  
Jun‐Cheng Zhang ◽  
Nan Gao ◽  
Lei Li ◽  
Shanshan Wang ◽  
Xiaofeng Shi ◽  
...  

Author(s):  
L.J. Chen ◽  
Y.F. Hsieh

One measure of the maturity of a device technology is the ease and reliability of applying contact metallurgy. Compared to metal contact of silicon, the status of GaAs metallization is still at its primitive stage. With the advent of GaAs MESFET and integrated circuits, very stringent requirements were placed on their metal contacts. During the past few years, extensive researches have been conducted in the area of Au-Ge-Ni in order to lower contact resistances and improve uniformity. In this paper, we report the results of TEM study of interfacial reactions between Ni and GaAs as part of the attempt to understand the role of nickel in Au-Ge-Ni contact of GaAs.N-type, Si-doped, (001) oriented GaAs wafers, 15 mil in thickness, were grown by gradient-freeze method. Nickel thin films, 300Å in thickness, were e-gun deposited on GaAs wafers. The samples were then annealed in dry N2 in a 3-zone diffusion furnace at temperatures 200°C - 600°C for 5-180 minutes. Thin foils for TEM examinations were prepared by chemical polishing from the GaA.s side. TEM investigations were performed with JE0L- 100B and JE0L-200CX electron microscopes.


Author(s):  
L. J. Chen ◽  
L. S. Hung ◽  
J. W. Mayer

When an energetic ion penetrates through an interface between a thin film (of species A) and a substrate (of species B), ion induced atomic mixing may result in an intermixed region (which contains A and B) near the interface. Most ion beam mixing experiments have been directed toward metal-silicon systems, silicide phases are generally obtained, and they are the same as those formed by thermal treatment.Recent emergence of silicide compound as contact material in silicon microelectronic devices is mainly due to the superiority of the silicide-silicon interface in terms of uniformity and thermal stability. It is of great interest to understand the kinetics of the interfacial reactions to provide insights into the nature of ion beam-solid interactions as well as to explore its practical applications in device technology.About 500 Å thick molybdenum was chemical vapor deposited in hydrogen ambient on (001) n-type silicon wafer with substrate temperature maintained at 650-700°C. Samples were supplied by D. M. Brown of General Electric Research & Development Laboratory, Schenectady, NY.


2013 ◽  
Vol 51 (5) ◽  
pp. 385-391 ◽  
Author(s):  
Gue-Serb Cho ◽  
Jung-Kyu Lim ◽  
Sonn-Yool Choi ◽  
Kyong-Hwan Choe ◽  
Sang-Sub Kim

2014 ◽  
Vol 29 (9) ◽  
pp. 941
Author(s):  
JIANG Jin-Long ◽  
WANG Qiong ◽  
HUANG Hao ◽  
ZHANG Xia ◽  
WANG Yu-Bao ◽  
...  

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