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61.
International Journal of Coal Science & Technology - Mineral phase characterization and thorough understanding of its transformation behavior during combustion are imperative to know the...  相似文献   
62.

Thermal loading induces modifications of the precipitation microstructure of Al–Si–Cu–Mg alloys. This study focuses on the effect of deformation on precipitation microstructure during thermomechanical loadings. Several specimens were thermomechanically cycled while others were exposed to the same thermal cycles without any mechanical loading. The nature and morphological characteristics of the precipitation microstructure of the thermomechanically cycled specimens are compared to those of the thermally aged ones, using transmission electron microscopy (TEM), in order to assess the effect of deformation on the precipitation microstructure and especially on the kinetics of precipitate growth. The absence of any significant effect of superimposed straining during thermal cycling is discussed. Implications for the prevision of yield strength degradation during service operation are briefly presented.

  相似文献   
63.

TiN coating is provided by reactive magnetron coating on a 304 stainless steel sample with a notch introduced at the edge of the sample. The sample is subjected to a tensile stress close to that of yield strength of the stainless steel. Optical and scanning electron microscopy characterization showed the distribution of buckled and delaminated regions around the notch. The distribution of the size of the partially delaminated regions of the film on the substrate is determined by transient thermo-reflectance. The stress field due to the notch is represented by that of a circular hole present at the tip and the variation of compressive and shear strain as a function of radial and angular coordinates is determined. The distribution of buckled and delaminated regions is found to follow the compressive strain variation around the notch. The size of the partially delaminated film is found to be larger near the notch and decreased with distance from the notch. The results illustrate that structures with regions of stress concentration should not be provided with brittle protective coatings that will delaminate.

  相似文献   
64.
Kosmatski  Ya. I.  Fokin  N. V.  Barichko  B. V.  Yakovleva  K. Yu.  Nikolenko  V. D. 《Metallurgist》2021,65(7-8):713-721
Metallurgist - The article presents the results of plastometric studies on hot deformation and studies on the hardening curves in cold deformation of EP450-Sh (12H12M1BFR-Sh) and EP823-Sh...  相似文献   
65.
Russian Journal of Non-Ferrous Metals - Using a Thermo-Calc software package (TCAl4.0 database), unexplored data concerning the phase composition and crystallization behavior of...  相似文献   
66.
Russian Journal of Non-Ferrous Metals - The process of making a weld using the heat-resistant EP693 alloy (Ni–Cr–W–Co–Co–Mo system) to make assemblies and components...  相似文献   
67.
Russian Journal of Non-Ferrous Metals - This article discusses methods for producing a material with gradient multilevel porosity by sintering layer-by-layer distributed α-Fe2O3 nanopowders...  相似文献   
68.
69.
The scheduling of maintenance for water distribution systems is a complex task encompassing a wide range of alternatives. The methodology presented in this paper can consider the major piping alternatives of replacing and cleaning, and relining. It also considers the potential of pumping improvements while accounting for the costs of maintenance, failure and operations for a multiple-period planning horizon. To solve the problem a nonlinear optimization model is linked with a network simulation model. The application showed that the procedure can determine solutions in reasonable times.  相似文献   
70.
The aim of this article is to introduce a meta-theoretical discussion in architectural research about materiality and its effect on everyday life and use. Taking a relational perspective, I distinguish between three different perspectives on materialities as described in theories in recent decades. From these perspectives I develop three possible conceptualisations of interobjectivity. The first perspective sees interobjectivity as collaboratively constructed ‘cross-road effects’. The second perspective sees interobjectivity as the process of stitching together material heterogeneities. The third perspective sees interobjectivity as the radiance of a persistent identity through different contexts. These three perspectives each contribute to the ways architectural objects and spaces interact and produce effects. These effects are often discussed within separate paradigms. Putting them together as different modalisations of interobjectivity enables a much richer empirical analysis, where the notion of ‘material effects’ can be differentiated and compared.  相似文献   
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