31 Result(s)

Article

Surface Energy Anisotropy of Diffusion-Induced Ni₃ A1 Crystals

Faceted crystals with well-defined {100}, {110}, and {1111 surfaces were observed in the interdiffusion zone during chemical interdiffusion of Ni/Ni 3 Al diffusion couple in the temperature range of 800°−1200°...

T. C. Chou, Y. T. Chou in MRS Online Proceedings Library (2011)

Article

The Effect of Boron on Microhardness in Ni₃ Al Polycrystals

In a recent MRS symposium, the effect of boron on grain boundary hardness (GBH) in Ni₃Al was reported. Addition of 0.2 at.% of boron decreased the GBH in all three sets of alloys tested (24, 25, and 26 at.% Al). ...

X. R. Qian, Y. T. Chou in MRS Online Proceedings Library (2011)

Article

Wet Oxidation in a Square Sandwich Composite of GaAs/AlAs/GaAs

Wet oxidation in a square sandwich composite, GaAs/AlAs/GaAs, with varying thickness of the AlAs layer was investigated in a temperature range of 400°C–480°C. At a given temperature and time, the oxidation dep...

Sun-Chien Ko, Sanboh Lee, Y.T. Chou in Journal of Electronic Materials (2007)

Article

Wet oxidation kinetics of AlAs at elevated temperatures

Wet oxidation in the AlAs layer sandwiched between two GaAs plates was investigated for the temperature range of 400 to 480 °C. The oxidation rate increased with increasing thickness of the AlAs layer. Theoret...

Sun-Chien Ko, Sanboh Lee, Hai-Lin Wang, Y. T. Chou in Journal of Materials Research (2003)

Article

Decomposition and thermodynamic property of metastable Fe-Zn solid solutions produced by mechanical alloying

Thermal decomposition of supersaturated single-phase body-centered cubic (bcc) Fe_100−xZn_x (5≤ x ≤65 at.%) solid solutions, processed via mechanical alloying of high-purity metal powders, was investigated using x-...

F. Zhou, Y. T. Chou, E. J. Lavernia in Journal of Materials Research (2002)

Article

Chemical stresses induced by grain-boundary diffusion in thin films

Chemical stresses induced by grain-boundary diffusion in thin films were analyzed. The stress distribution consisted of both tension and compression fields, and its characteristics were similar to those obtain...

W. L. Wang, Y. T. Chou, Sanboh Lee in Journal of Materials Research (2001)

Article

Chemical stresses induced by grain-boundary diffusion

Based on Whipple-Suzuoka solutions, the chemical stresses induced by grain-boundary diffusion under constant- and instantaneous-source concentrations are investigated. For a finite boundary, the chemical stres...

W. L. Wang, Y. T. Chou, Sanboh Lee in Metallurgical and Materials Transactions A (1998)

Article

Fractal characterization of the fracture surface of a high-strength low-alloy steel

The fractal dimension of fracture surfaces of a high-strength low-alloy steel (ASTM A710) has been measured using different ruler lengths. The fractal dimension increases with increasing impact toughness, E, a...

J. C Hsiung, Y. T Chou in Journal of Materials Science (1998)

Article

Thermal and mechanical properties of porous Y-PSZ/zircon composites

 The thermal and mechanical properties of sintered porous composites of yttria-partially-stabilized-zirconia (Y-PSZ) and zircon (ZrSiO₄) were investigated for a broad range of compositions. Fracture strengths of ...

Y. P. **, Y. T. Chou in Material Research Innovations (1998)

Article

An experimental study of the interaction of internal cracks in PMMA

Internal cracks in polymethyl methacrylate (PMMA) specimens were generated by pulsed laser light. The interactions of coplanar cracks, parallel cracks, and cracks in T and H configurations were investigated. T...

Y. Z LI, Y. T CHOU in Journal of Materials Science (1997)

Article

Analysis of mean square penetration depth in grain boundary diffusion

Exact and approximate expressions for mean square penetration depth (MSPD) in grain boundary diffusion are derived. The MSPDs in boundary diffusion are functionally different from those in lattice diffusion. T...

Y. T. Chou, Y. Z. Li, C. T. Liu in Metallurgical and Materials Transactions A (1996)

Article

On the interaction of internal cracks in polymethyl methacrylate

Y. Z. Li, Y. T. Chou in Journal of Materials Science Letters (1996)

Article

Deformation mechanism map for creep in YBa₂Cu₃O_7−x

A deformation mechanism map with grain size and stress as variables was constructed for creep in YBa₂Cu₃O_7−xat 850 and 950 °C. Theoretical models of Nabarro-Herring, Coble, and power-law creep were used for the c...

J. Yun, M. P. Harmer, Y. T. Chou in Journal of Materials Science (1995)

Article

Growth and Facet Orientations in Single-Phase TiAl Single Crystals

Single crystals of single-phase TiAl alloy (Ti-56 at. % Al) have been grown at 10mm/h solidification rate in an ASGAL FZ-SS35W Optical Floating Zone Furnace. The orientations of the resulting single crystals h...

R. Mahapatra, H. Lin, D. P. Pope, Y. T. Chou in MRS Online Proceedings Library (1994)

Article

Fracture behavior of fused quartz with laser-induced internal flaws

Pulsed-laser light was used to generate internal flaws in fused quartz. The size of the flaw produced was proportional to the amount of laser pulse energy above a threshold value of 2.5 mJ. Specimens of differ...

Y. Z. Li, M. P. Harmer, Y. T. Chou in Journal of Materials Research (1994)

Article

Observation of laser-induced internal flaws in PMMA

B. Zhou, Y. T. Chou in Journal of Materials Science Letters (1993)

Article

Alloy softening in Ni₃Al polycrystals

The alloying effect of boron on localized deformation in Ni₃Al polycrystals containing 24–26 at% AI was studied using microhardness indentation. Alloy softening was observed both along the grain boundaries and in...

X. R. Qian, Y. T. Chou in Journal of Materials Science (1992)

Article

Cation interdiffusion between thick film of YBa₂Cu₃O_7-δ and ceramic substrate

Thick films of superconducting oxides, YBa₂Cu₃O_7-δ, were successfully made by conventional screen-printing technology on Al₂O₃, MgO, and ZrO₂ substrates. Interdiffusion between the superconductive film and substr...

X. M. Li, Y. T. Chou, Y. H. Hu, C. L. Booth in Journal of Materials Science (1991)

Article

Uphill diffusion in YBa²Cu³O^7-δ thick film on Al₂O₃ substrate

X. M. Li, Y. T. Chou, Y. H. Hu, C. L. Booth in Journal of Materials Science Letters (1990)

Article

Interfacial Failure In Ti/Sio₂ and Ti/AIN System And Temperature Dependence Of Hardness Of AIN

The load dependence of interracial failure induced by microindentation has been studied. It is demonstrated experimentally that substrate lateral defects induced by indentation contribute significantly to inte...

T. Liu, R. Notis, Y. T. Chou in MRS Online Proceedings Library (1989)