Further Experiments on the High-Temperature Internal Friction Peak in High-Purity Single Crystal Aluminium

By using a low frequency inverted torsion pendulum, the high temperature internal friction spectra of Al-0.02wt%Zr and Al-0.1wt%Zr alloys were investigated respectively. In Al-0.02wt%Zr alloy, the conventional grain boundary internal friction peak (Pg) is observed with some small unstable peaks. In Al-0.1wt%Zr alloy, the bamboo peak is observed to appear at the high temperature side of the conventional grain boundary internal friction peak. The conventional grain boundary internal friction peak decreased and moved to higher temperature. The bamboo peak owns an activation energy of 1.75eV. When average grain size exceeded the diameter of samples, Pb strength was reduced and its position was shifted to a lower temperature. Based on the grain boundary sliding model, Pg and Pb peaks were explained. Their dependence on annealing temperature and time was determined by considering the effects of contained Ce atoms and other impurities on the relaxation across grain boundary.

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Internal Friction and Dynamic Modulus in Ultra-High Temperature Ru-Nb Functional Intermetallics / Tarcie Wewnętrzne I Moduł Dynamiczny W Bardzo Wysoko Temperaturowych Funkcjonalnych Związkach Międzymetalicznych Z Układu Ru-Nb

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0490 ◽

2015 ◽

Vol 60 (4) ◽

pp. 3069-3072

Author(s):

M.L. Nó ◽

L. Dirand ◽

A. Denquin ◽

J. San Juan

Keyword(s):

High Temperature ◽

Internal Friction ◽

Martensitic Transformations ◽

Time Dependent ◽

Structural Defects ◽

Complete Analysis ◽

Internal Friction Peak ◽

Thermally Activated ◽

Temperature Ranges ◽

Lower Temperature

In the present work we have studied the high-temperature shape memory alloys based on the Ru-Nb system by using two mechanical spectrometers working in temperature ranges from 200 to 1450ºC and -150 to 900ºC. We have studied internal friction peaks linked to the martensitic transformations in the range from 300 to 1200ºC. In addition, we have evidenced another internal friction peak at lower temperature than the transformations peaks, which apparently exhibits the behaviour of a thermally activated relaxation peak, but in fact is a strongly time-dependent peak. We have carefully studied this peak and discussed its microscopic origin, concluding that it is related to the interaction of some structural defects with martensite interfaces. Finally, we perform a complete analysis of the whole internal friction spectrum, taking into account the possible relationship between the time-dependent peak and the martensitic transformation behaviour.

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INDIUM SEMI-CONDUCTOR GRADE

Alloy Digest ◽

10.31399/asm.ad.in0003 ◽

1998 ◽

Vol 47 (3) ◽

Keyword(s):

Compressive Strength ◽

Crystal Growth ◽

High Temperature ◽

Physical Properties ◽

Single Crystal ◽

High Purity ◽

Electronic Device ◽

Compound Semiconductors ◽

Temperature Performance ◽

Device Technology

Abstract Semiconductor grade indium products are available in several high purity levels including 7N, 6N5WCI (with controlled impurities), 6N5, and 6N. High purity indium is used in electronic device technology, crystal growth in epitaxial processes, and the production of single crystal III-V compound semiconductors. This datasheet provides information on composition, physical properties, microstructure, hardness, elasticity, tensile properties, and compressive strength. It also includes information on high temperature performance. Filing Code: IN-3. Producer or source: Indium Corporation.

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