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111.
The effect of the degree of degradation of the components of a model municipal plastic waste (a mixture of low-density polyethylene, high-density polyethylene, polypropylene and high-impact polystyrene) on the toughness and stability of recyclates compatibilised with a cooperative compatibilisation system (a mixture of ethylene-propylene statistical and styrene-butadiene block copolymers with a secondary amine-based stabiliser) was studied. It was shown that good impact strength was achieved for recyclates having components with a low or medium degree of degradation. Mechanical properties of recyclates having the components with a high degree of degradation are deteriorated. The addition of the cooperative compatibilisation system leads to a higher thermo-oxidative stability of recyclates irrespective of the degree of degradation of their components. Photo-oxidative stability of the recyclates is low but it can be improved to a satisfactory level by the addition of carbon black or a commercial photo-stabiliser. 相似文献
112.
A. Blaise C. Baravian J. Dillet L.J. Michot S. André 《Journal of Polymer Science.Polymer Physics》2012,50(5):328-337
This study presents quantitative results related to in situ investigation of the microstructural evolutions of high‐density polyethylene with deformation. These results were obtained thanks to a novel technique (IPSLT) based on the polarized light scattering transport phenomenon. The heterogeneities produced during whitening of the polymer bulk are characterized at the mesoscale level (from hundred of nanometers to a few micrometers). The technique is described as well as the identified parameters it provides, namely: the average size of the scatterers, the anisotropy developed in the medium, and the light transport length, representative of both the volume fraction and size of the heterogeneities. Results obtained during video‐controlled tensile experiments confirm those obtained previously with X‐ray microtomography. They put forward the role of morphological transformations of the amorphous/crystalline phases (especially regarding the creation of fibrillar assemblies) rather than the cavitation phenomenon. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
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114.
孔型立轧过程的三维刚塑性有限元分析 总被引:4,自引:0,他引:4
采用三维刚塑性有限元法对2S-Al板孔型立轧稳态过程进行了分析和比较,所得轧件断面形状,轧制力及轧制力矩与文献「1」的实验结果吻合很好,计算精度有所提高。 相似文献
115.
V.E. Panin V.S. Pleshanov S.A. Kobzeva S.P. Burkova 《Theoretical and Applied Fracture Mechanics》1998,29(2):99-102
Studied is the mesoscale behavior of plastic deformation and fracture of weld joints for austenic steels. Large-scale rotational modes of deformation in heat affected zones are identified with the first stage of formation of band structures; it is related to the “traveling neck” phenomenon in the base metal. The second stage is connected with crack generation and the state of affairs in the heart-affected zone. 相似文献
116.
117.
朱锡雄 《宁波大学学报(理工版)》1991,(1)
总结评述了固体材料表现出韧或脆性,也即变形和断裂及其相互转变的力学条件。收列大量事例以说明变形—断裂转变的各种表现形式及各种条件参数的影响。提出一种能概括各种变形和断裂行为的变形—断裂转变示图。总结表明,材料的断裂行为主要受尺寸参数D和性能参数(K_c/σs)~2控制,在不同的状态条件下,可表现为弹性变形、弹性断裂、弹塑性变形、弹塑性断裂、塑性流动或倒塌、全塑性断裂等多种力学行为。 相似文献
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119.
Investigations were carried out for laser-effected darkening and damage-free laser marking on thermoplastic elastomers (TPEs). Titanium dioxide (TiO2) was studied as the laser-sensitive additive to the TPEs for its role in enhancing laser marking contrast and its effect on the TPE properties. Laser beam characteristics, processing variables and percentage loading of TiO2 in the TPEs were found to have significant effect on the marking contrast. Surface damage-free and high contrast marking have been achieved with short pulse UV lasers. The laser-effected darkening was found to penetrate into the material in the order of a few tens of microns. XPS analysis was carried out to understand the laser-effected darkening mechanism. Potential applications of the technique are highlighted. 相似文献
120.
Investigators have viewed the stress rate in two different ways: the material (body-fixed) point of view and the Eulerian point of view. We discuss the Zaremba–Jaumann rate and Oldroyd’s rate from the material viewpoint and apply them to the material formulation of a theory of plasticity for materials undergoing anisotropic plastic deformation. Significant advantages of the material formulation are that the derivation of equations is straight forward, the distortion of yield surface can be easily accounted for, and the issue of self-consistent elastic equation does not arise. 相似文献