低周波振動法による内部摩擦の測定(Ⅰ) : 最小2乗法によるスネーク緩和スベクトルの分離

URI http://harp.lib.hiroshima-u.ac.jp/it-hiroshima/metadata/4208
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Title
低周波振動法による内部摩擦の測定(Ⅰ) : 最小2乗法によるスネーク緩和スベクトルの分離
Title Alternative
Measurement of Intenal Friction by Means of The Low Frequency Method (Ⅰ) : Resolution of The Snoek Relaxation Spectrum by The Least-squares Method
Author
氏名 川辺 尚志
ヨミ カワベ ヒサシ
別名 Kawabe Hisashi
Abstract

An attempt aiming at experimentally verifying a material damping model for relaxation behaviors, i. e. some observation on an asymmetrical damped oscillation, has been made through the Snoek relaxation mechanism in mild steel wires. The specimens containing 0.063 wt % of carbon and 0.004 wt % of nitrogen and having the sizes (0.71 φ or 1.0 φ×300 mm) are twisted using an inverted torsion pendulum, oscillated at the frequency range 0.4 Hz to 1.1 Hz, and heated from -40℃ to 250℃ for the measurement of internal friction and modulus deffects. As was anticipated, the inclination for the damped oscillation curves to deviate from the time base axis to the initially twisted side is not observed markedly, but the the resolution, by the least-squares method, from the observed damping data into the normal nitrogen and carbon peaks states that first, in a specimen fully annealed from γ-range, whether it may be treated with the quenching from 600℃ or not, is exihibited only the N-peak, and then, in one annealed at 650℃ for 1 hr and then quenched therefrom, the superposition of N-peak and C-peak is manifested, and that, in one annealed at 700℃, 1 hr, and quenched therefrom, almost all the damping is responsible for free carbon interstitials. Such evidences are therefore interpreted as implying the following: (1) the total nitrogen content of 0.004 wt % contributes to the stress induced ordering damping as free interstitials in α; and (2) the variation of the carbon peak heights with heat treatment conditions is closely associated with the behaviors for solute carbon atoms to aggregate to the sub-boundaries or grain boundaries, to be freed from them, to precipitate into the compounds of carbide or nitride, and to form the Cottrell atmosphere.

Journal Title
広島工業大学研究紀要
Volume
11
Spage
115
Epage
125
Published Date
1977
Publisher
広島工業大学
ISSN
03851672
NCID
AN0021271X
Language
jpn
NIIType
Departmental Bulletin Paper
Text Version
出版社版
Old URI
Set
it-hiroshima