著者
浜田 幸一 井坂 和実 土居 大治 米満 善久 岩崎 信吾
出版者
社団法人日本鉄鋼協会
雑誌
鐵と鋼 : 日本鐡鋼協會々誌 (ISSN:00211575)
巻号頁・発行日
vol.88, no.2, pp.66-72, 2002-02

Clad steel sheet is formed by cladding different metals and used for the functional material, which has convenient characteristics of each metal. Especially, a lot of stainless steel/aluminum clad strip is produced for electromagnetic rice cookers which are in demand because of the higher thermal conductivity, having magnetism and corrosion resistance. For the demand, continuous cladding technology of the wide width stainless steel/aluminum strip has been developed by warm rolling after the rapid heating process. Recently, much higher uniformity for peeling strength is required as the market grows. So, a new heating process, in which uniform heat generation is achieved by the electric resistance of metals and the directly applied current, is developed in place of the conventional process of induction heating. After solving some technical problems about sparks and temperature uniformity, direct resistance heating equipment have installed in the manufacturing line. As the result, high-quality clad steel sheets, which have the uniform peeling strength, can be produced by the improvement of temperature deflection on rolling.
著者
豊貞 雅宏 藤井 英輔 野原 和宏 川口 喜昭 有持 和茂 井坂 和実
出版者
The Japan Society of Naval Architects and Ocean Engineers
雑誌
日本造船学会論文集 (ISSN:05148499)
巻号頁・発行日
vol.1987, no.161, pp.343-356, 1987 (Released:2009-09-16)
参考文献数
20
被引用文献数
8 10

It is well known that fracture toughness value is affected by strain rate. As for strain rate, the dependency of fracture toughness on fracture parameter rate has been usually studied. In the linear fracture mechanics, fracture parameter rate (dK/dt) is directly related to strain rate. However, in the non-linear fracture mechanics, the relation between fracture parameter rate (dδ/dt, dJ/dt) and strain rate has not yet been made clear. Therefore, in the safety assessment of real structures, non-linear fracture parameter can not be applied in case of which the effect of the strain rate on the fracture toughness needs to be considered.In this paper, fracture initiation point is assumed to be the tip of the intensely deformed non-linear zone defined by Rice, which is considered to show the maximum triaxial constraint. Then the strain rate at the supposed fracture initiation point is given in connection with remote strain rate which corresponds to the strain rate in non-cracked plate. By use of the newly difined strain rate, strain rate-temperature parameter is determined, which represents the effect of strain rate on fracture toughness. Compact tension tests and COD tests with different strain rate and temperature, as well as KId tests are carried out to verify above conception.