著者

畑 敏雄

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.17, no.175, pp.322-325, 1968-04-15 (Released:2009-07-09)

参考文献数

12

被引用文献数

2 3

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Two theories of fracture of viscoelastic materials are hereunder proposed, the one based on a simple model and the other generalized thereupon, and an attempt is made to explain the dependence of stress and strain at break on temperature and strain rate as particularly was called the failure envelope by T.L. Smith.The model of the first simple theory consists of two Maxwell elements (system 1 and 2) connected in parallel and the following criteria for fracture are introduced.(1) Fracture occurs first at the system 1, and then at the system 2 where the whole load is applied.(2) Fracture of the system 1 occurs either when the spring reaches the critical strain ε11c (in the case of large strain rate) or the dashpot does so to ε12c (in the case of small strain rate).For the deformation of constant rate R, the following results are obtained, which explain the experimental behaviors well at least qualitatively.at larger strain ratesat smaller strain rateswhere σ, ε, G and τ follow the ordinary use and suffices 1 and 2 mean system 1 and 2 respectively and the suffix b does so "at break".Next the above model theory is so extended to the generalized Maxwell bodies as to read that the stress of deformation at constant rate is expressed by the equationIn this case the storage energy Wst and the dissipation energy Wdis of deformation are calculated after Landel, and the following criterion is introduced, that is, the sample breaks either when the elastic part with its own modulus G0 (the instantaneous modulus) reaches the critical strain ε1c or the viscous part with its steady flow viscosity η0 reaches the critical strain ε2c.The results are given asat larger strain ratesat smaller strain rateswhere G' and η' are dynamic modulus and viscosity respectively. Considering the dependence of G' and η' on shear rate and temperature, the failure envelope can be explained with these equations.

著者

畑 敏雄

出版者

公益社団法人 高分子学会

雑誌

高分子 (ISSN:04541138)

巻号頁・発行日

vol.22, no.2, pp.58-66, 1973-02-01 (Released:2011-09-21)

参考文献数

46

被引用文献数

2 1

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界面の状態や構造が,複合材料の性質に大きな影響を与えるだろうということは誰でも想像することであるが,それがどんな影響かということになるとあまりよくわからない。それは複合材料の性質が, 複合素材, 複合過程, 複合状態のそれぞれに起因するいろいろな要素のからみあった結果として現われるからで,このなかから界面構造の影響だけを取り出して議論することはむずかしい。表面改質の話でもすれば少しは実際の役にたつかもしれないが,金属,無機材料, プラスチックでみんなやり方が違うし, 組み合わせる相手によってまた特殊である。何か統一的な見方はないか,と界面の安定条件から書き出してみたが… … … 。

著者

畑 敏雄

出版者

社団法人日本化学会

雑誌

化学と教育 (ISSN:03862151)

巻号頁・発行日

vol.37, no.3, pp.258-262, 1989-06-20