著者

石塚 丈洋

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.65, no.635, pp.1520-1527, 1999-07-25

被引用文献数

1

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For the purpose of investigating the macroscopic and microscopic elastoplastic deformation behavior of two-phase composites : W-Ni-Fe alloys, the constitutive relations of W-Ni-Fe alloy and its microconstituents were measured by the Hopkinson pressure bar testing and usual compression testing, and then the elastoplastic deformation behavior of W-Ni-Fe alloys in uniaxial compression was analyzed using the micromechanics-based analysis method. The main conclusions are summarized as follows ; (1) The work hardening tendency of W-Ni-Fe alloy is in keeping with that of pure tungsten particle phase which is B.C.C. metal. (2) Measured flow stresses of W-Ni-Fe alloy under high strain rate loading are smaller than analyzed ones, due to local failure in the matrix phase of W-Ni-Fe alloy. (3) The compressive residual stresses in the particle phase are produced at the cooling stage in sintering. (4) The micromechanics-based analysis method can precisely analyze the elastoplastic deformation behavior of two-phase composites until large deformation.

著者

石塚 丈洋

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.64, no.625, pp.2308-2314, 1998-09-25

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Numerical simulations are effective approach for the safety design of machines and structures subjected to impact loading and the investigation of impact phenomena. Dynamic mechanical properties which accurately model the response of materials to impact loading are necessary for such numerical simulations. In this research, the equation of state and failure criteria are measured by plate impact testing, and then the accuracy of these measured dynamic mechanical properties is evaluated based on numerical simulation results. Followings are useful information obtained. (1) The equation of state and failure criteria measured by plate impact testing are sufficiently accurate for numerical simulations. (2) Pure W which is the brittle metal, follows stress-dependent failure criterion. (3) W-Ni-Fe alloys which are the ductile metals, follow time-dependent failure criterion. (4) W-Ni-Fe alloy has the lower critical value for spall failure than its matrix phase. (5) The failure strains of W-Ni-Fe alloys depend on the state of stress.