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The tribological properties of the high-strength and high-modulus ultrahigh molecular weight polyethylene (UHMWPE) film and the UHMWPE composites reinforced by multiwalled carbon nanotubes (MWCNT/UHMWPE) were investigated using a nanoindenter and atomic force microscope (AFM). The MWCNT/UHMWPE composites films exhibited not only high wear resistance but also a low friction coefficient compared to the pure UHMWPE films. We attribute the high wear resistance to the formation of the new microstructure in the composites due to the addition of MWCNTs. Copyright (C) 2006 John Wiley & Sons, Ltd.

The tribological properties of the high-strength and high-modulus ultrahigh molecular weight polyethylene (UHMWPE) film and the UHMWPE composites reinforced by multiwalled carbon nanotubes (MWCNT/UHMWPE) were investigated using a nanoindenter and atomic force microscope (AFM). The MWCNT/UHMWPE composites films exhibited not only high wear resistance but also a low friction coefficient compared to the pure UHMWPE films. We attribute the high wear resistance to the formation of the new microstructure in the composites due to the addition of MWCNTs. Copyright (C) 2006 John Wiley & Sons, Ltd.

The tribological properties of the high-strength and high-modulus ultrahigh molecular weight polyethylene (UHMWPE) film and the UHMWPE composites reinforced by multiwalled carbon nanotubes (MWCNT/UHMWPE) were investigated using a nanoindenter and atomic force microscope (AFM). The MWCNT/UHMWPE composites films exhibited not only high wear resistance but also a low friction coefficient compared to the pure UHMWPE films. We attribute the high wear resistance to the formation of the new microstructure in the composites due to the addition of MWCNTs. Copyright (C) 2006 John Wiley & Sons, Ltd.

The rapid developments of micro-electro-mechanical systems (MEMS) make progress in the research on the tension measurements of minisize materials. The paper is specially focused on introducing several typical tension ways, and cited in illustration of the tension measuring principles for drive, load and displacement and the difficulties of sample handling, alignment and gripping. Finally, a discussion of the future on tension measuring principle is given.

The rapid developments of micro-electro-mechanical systems (MEMS) make progress in the research on the tension measurements of minisize materials. The paper is specially focused on introducing several typical tension ways, and cited in illustration of the tension measuring principles for drive, load and displacement and the difficulties of sample handling, alignment and gripping. Finally, a discussion of the future on tension measuring principle is given.

The rapid developments of micro-electro-mechanical systems (MEMS) make progress in the research on the tension measurements of minisize materials. The paper is specially focused on introducing several typical tension ways, and cited in illustration of the tension measuring principles for drive, load and displacement and the difficulties of sample handling, alignment and gripping. Finally, a discussion of the future on tension measuring principle is given.

A theoretical analysis is presented for the dynamic viscoplastic response of thick-walled spherical shells subjected to internal pressure. The material is rigid-viscoplastic and incompressible; the viscoplastic constitutive equations due to Hohenemser and Prager are used. As a specific example, the quasi-static case is also studied.

This paper concerns the dynamic behaviour of rigid, perfectly plastic simply supported beams with finite deflections by considering both bending moments and axial forces. In the case of rectangular pressure pulse loading, approximate rigid-plastic theoretical solutions are obtained for both medium load and high load; to this end a parabolic law between bending moment and axial force as yield condition is approximated by a circumscribing or an inscribing rectangle. The concept of Saturation Impulse is put forward for the dynamic response of rigid, perfectly plastic structures with finite deflections subjected to rectangular pressure pulse. The value of dimensionless saturation impulse for both simply supported and fully clamped beams are given.

The transverse shear failure of a circular plate with an infinitely large outside radius, made from a rigid, perfectly plastic material, is considered. The plate has a rigid central cylindrical boss which is subjected to an initial impulsive velocity which causes a circular transverse shear hinge to develop at the interface between the boss and the plate. Two models are adopted in this paper. Rotatory inertia are disregarded in the first, the second retains the influence of rotatory inertia as well as bending moments. It is illustrated that whether a shear failure occurs or not at the interface, where the initial velocity has discontinuity, depends on the nondimensional initial kinetic energy, the material property and two ratios, one is the thickness of the plate to the radius of the boss, and the second is the density ratio of the boss to the plate. It is shown by the comparison between the two models that the influence of the rotatory inertia of the plate on the shear failure are not negligible.

This paper concerns the dynamic behaviour of rigid, perfectly plastic simply supported beams with finite deflections by considering both bending moments and axial forces. In the case of rectangular pressure pulse loading, approximate rigid-plastic theoretical solutions are obtained for both medium load and high load; to this end a parabolic law between bending moment and axial force as yield condition is approximated by a circumscribing or an inscribing rectangle. The concept of Saturation Impulse is put forward for the dynamic response of rigid, perfectly plastic structures with finite deflections subjected to rectangular pressure pulse. The value of dimensionless saturation impulse for both simply supported and fully clamped beams are given.

The transverse shear failure of a circular plate with an infinitely large outside radius, made from a rigid, perfectly plastic material, is considered. The plate has a rigid central cylindrical boss which is subjected to an initial impulsive velocity which causes a circular transverse shear hinge to develop at the interface between the boss and the plate. Two models are adopted in this paper. Rotatory inertia are disregarded in the first, the second retains the influence of rotatory inertia as well as bending moments. It is illustrated that whether a shear failure occurs or not at the interface, where the initial velocity has discontinuity, depends on the nondimensional initial kinetic energy, the material property and two ratios, one is the thickness of the plate to the radius of the boss, and the second is the density ratio of the boss to the plate. It is shown by the comparison between the two models that the influence of the rotatory inertia of the plate on the shear failure are not negligible.

A theoretical analysis is presented for the dynamic viscoplastic response of thick-walled spherical shells subjected to internal pressure. The material is rigid-viscoplastic and incompressible; the viscoplastic constitutive equations due to Hohenemser and Prager are used. As a specific example, the quasi-static case is also studied.

A theoretical analysis is presented for the dynamic viscoplastic response of thick-walled spherical shells subjected to internal pressure. The material is rigid-viscoplastic and incompressible; the viscoplastic constitutive equations due to Hohenemser and Prager are used. As a specific example, the quasi-static case is also studied.

This paper concerns the dynamic behaviour of rigid, perfectly plastic simply supported beams with finite deflections by considering both bending moments and axial forces. In the case of rectangular pressure pulse loading, approximate rigid-plastic theoretical solutions are obtained for both medium load and high load; to this end a parabolic law between bending moment and axial force as yield condition is approximated by a circumscribing or an inscribing rectangle. The concept of Saturation Impulse is put forward for the dynamic response of rigid, perfectly plastic structures with finite deflections subjected to rectangular pressure pulse. The value of dimensionless saturation impulse for both simply supported and fully clamped beams are given.

The transverse shear failure of a circular plate with an infinitely large outside radius, made from a rigid, perfectly plastic material, is considered. The plate has a rigid central cylindrical boss which is subjected to an initial impulsive velocity which causes a circular transverse shear hinge to develop at the interface between the boss and the plate. Two models are adopted in this paper. Rotatory inertia are disregarded in the first, the second retains the influence of rotatory inertia as well as bending moments. It is illustrated that whether a shear failure occurs or not at the interface, where the initial velocity has discontinuity, depends on the nondimensional initial kinetic energy, the material property and two ratios, one is the thickness of the plate to the radius of the boss, and the second is the density ratio of the boss to the plate. It is shown by the comparison between the two models that the influence of the rotatory inertia of the plate on the shear failure are not negligible.