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Introduction Phase segregation is a common phenomenon taking place during thixoforming processes, which results in heterogeneity of products in terms of composition and properties.
As-rheocast microstructure of ZA27 alloy prepared via mechanical stirring.
Liquid pressure gradient is also affected by extrusion ratio; increasing extrusion ratio through either increasing ram diameter or reducing cavity diameter intensifies pressure gradient within the liquid phase.
In view of our results, liquid phase in the case of tests at 175mm/s has been powerful and therefore, the duration of its contact with the solid phase, before reaching the clearance, has become the factor controlling segregation severity.
Conversely, for the tests at the ram speed of 60mm/s, ineffective liquid phase has merely exuded from the solid phase and the effect of pressure gradient within the liquid phase has become the dominant factor controlling segregation index.

Superplastic Deformation Behavior and Cavity Formation of Ti55 Titanium Alloy Zhangguang Liu1,2,a*, Peijie Li1,b 1National Center of Novel Materials for International Research, Tsinghua University, Beijing 100084, China 2Beijing Xinghang Electro-mechanical Equipment Co., Ltd., Beijing 100074, China aliuzg13@mails.tsinghua.edu.cn, blipj@mail.tinghua.edu.cn Keywords: Ti55; Superplasticity; Titanium alloy, Cavity, Strain rate sensitivity index.
Due to different and incompatible material performance and thermal expansion performance between hard rare earth grains and titanium alloy material matrix, thermo-mechanical treatment of Ti55 titanium alloy material leads to stress concentration at the phase interface between rare earth phase grains and material matrix, which can easily result in defects around rare earth grains.
On the other hand, they may negatively affect grain boundary slips during superplastic deformation, and lead to cavities at interfaces between different phases.
Since cavities was restricted around the rare earth phase during deformation, and rare earth phase grains help improve tensile elongation of Ti55 alloy, thus a balance can be achieved between these two factors.
Study on recrystallization and correlated mechanical properties in Mo-modified Zr-Nb alloys, Mater.

Material Characterization and Modelling Technical material properties.
Table 1: Mechanical material parameters obtained from tensile tests.
The FLC model of Keeler is parameterized by the mechanical material properties evaluated in tensile tests.
A factor 2 downscaled assembly is utilized which also means reducing the specimen dimensions.
Paul, “Controlling factors of forming limit curve: A review,” Advances in Industrial and Manufacturing Engineering, vol. 2, p. 100033, May 2021, doi: 10.1016/j.aime.2021.100033

However, the double aging heat leads to a very high improvement of mechanical properties [9].
Djemmal, Study of mechanical and electrical properties of AlMgSi alloys, Ann.
Guemini, Study of mechanical properties and precipitation reactions in low copper containing Al-Mg-Si alloy, Arch.
Serradj, Effect of natural and artificial aging on the mechanical properties of two Al-Mg-Si alloys, Inter.
Xu, Effects of the Mg/Si ratio on microstructure, mechanical properties and precipitation behavior of Al-Mg-Si-1.0wt%-Zn alloys. 

Properties of cement with a low content of barium oxide (5.5%) are close to the properties of the standard Portland cement.
Special properties of barium cements make them suitable for structures affected by prolonged exposure to high temperatures and ionizing radiation [1-3].
With the same water-cement ratio equal to 0.40, this cement showed the highest fluidity of cement paste, and its mechanical properties were found to be the lowest.
For values of q, ΔT must be multiplied by a constant factor in brackets in the Eq. 2.
Topcu, Properties of heavyweight concrete produced with barite, Cem. and Concr.

Introduction Environmental issues and energy security increasingly affect our lives.
Wind turbine ‒ a set of technical devices designed for converting the kinetic energy of wind stream into mechanical energy of generator rotor rotation.
It is known for example that the shape of the building affects thermal insulation properties (due to convex qualities of building) [18].
Furthermore, it affects the speed and direction of wind that ventilate building or construction [19].The project proposal to strengthen the wind flow by streamlining facades is considered in this article.
Due to the fact that the site of the school is elevated, and the surrounding buildings are not represented by high-rise buildings, which would significantly affect the wind direction and speed, height of the tower should take no more than the average height of the school (5-10 meters).

Introduction Significant grain refinement down to the submicron scale is one of the most promising routes for improving the mechanical properties of structural steels and alloys.
The ultrafine-grained metallic materials possess a beneficial combination of mechanical properties, namely, high strength at ambient temperature and enhanced workability at elevated temperatures [1].
Note here that the large fractions of high-angle boundaries obtained at a relatively small strain of 0.5 in Fig. 4 could be affected by the original grain boundaries.
Langdon, Twenty-five years of ultrafine-grained materials: Achieving exceptional properties through grain refinement, Acta Mater. 61 (2013) 7035-7059
Lagneborg, A controlling factor for dynamic recrystallization, Scripta Metall. 9 (1975) 59-66

Effect of Sericin Concentration on the Growth and Morphology of Escherichi Coli Rui Xue1, a, Bingjie Chen1, Xiao Jin2, Qingsong Zhang1, b*, Meiling Han1 and Congcong Liang1 1School of Material Science and Engineering, State Key Laboratory of Hollow Fiber Membrane Materials and Processes, Tianjin Polytechnic University, Tianjin 300387, China 2Department of mechanical engineering, Yantai Nanshan University, Yantai 265713, China a15122529363@163.com, bzqs8011@163.com Keywords: Sericin, Escherichi coli, Proliferation, Morphology, Biocompatibility.
Besides, it can promote bacterial protein expression without affecting cell morphology.
In previous works [11-12], our research group has prepared a series of semi-IPN SS (Silk Sericin)/PNIPAM (polyN-isopropylacrylamide) hydrogels, and the structure, morphology and properties have been deep studied.
Yamada, Preparation of silk protein sericin as mitogenic factor for better mammalian cell culture, J.

Cutters with indexable inserts have higher economic efficiency compared to cutters with brazed cutting tips due to the following factors [15-17]: - no need to resharpen knives with brazed tips, as a result resharpening expenses are excluded; - a cutter construction has no knives so it makes the construction simpler and cheaper; - indexable inserts are fixed mechanically, so there is no need to braze and then to rebraze them at the end of their efficient life
The brazed cutting tips can be hardly coated due to brazed joints whose properties can be changed when heated to the temperature of the coating.
Solonitsyn, Increasing the technological capabilities of the process finish machining of gear wheels, Journal of mechanical engineering. 11 (2005) 47-49
Zaitsev, The Selection of the optimum process of machining gear teeth, Journal of mechanical engineering. 7 (2008) 40-41
Kharlamov, Improving the efficiency of processing of straight-toothed bevel gears, Science intensive technologies in mechanical engineering. 3 (2015) 8-16

Numerical Simulation on the Effect of Mist on Impingement Cooling of Double Chamber Model Guangjie Liu1, 2, a, Tao Xu1,b, Haichao Ge1,c, Zhenglei Yu1,d and Tatsuo Yoshino1,e,* 1 College of Mechanical Science & Engineering, Jilin University, Changchun, PR China 2 College of Computer Science and Technology, Changchun Normal University, Changchun, PR China a 756058599@qq.com, b 791181007@qq.com, c yuzl08@mails.jlu.edu.cn, d 905830811@qq.com, e yoshinojlu@sina.com * Corresponding author Keywords: Impingement cooling, Computational fluid dynamics, Cooling effectiveness, Double chamber model Abstract.
Although, the mechanical stresses experienced by the TP are within acceptable limits compared to other parts, high temperatures and large temperature gradients affect the structural integrity of these components, which makes TP a very critical component of a gas turbine in structural and thermal designs.
Assumption of the solid wall of the quarter torus is formed with a hypothesis of negligible thermal resistance by conduction, the thermal properties of the material were considered by Nimonic 263.
The convergence criteria of the steady-state solution are judged by the reduction in the mass residual by a factor of 6, typically, in 2000 iterations.