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Introduction Within the last years, mechanical joining processes have proven to be economical and reliable in the automotive manufacturing.
According to the standard DIN 8593, the mechanical joining processes are assigned to the group "joining by forming".
It has become an established mechanical joining process, especially in applications where thermal joining processes cannot be applied.
Besides the insufficient optical properties, these cracks impair the corrosion resistance and are to be suppressed.
Unfortunately, this reduction of Cmax goes along with a decrease of the interlock f, which might affect the joint strength.

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.

The regenerative type is found to be the main limiting factor to the production rate in most machining processes Fig. 1 [3].
Frictional properties of the tool work piece interaction affect the dynamic cutting force characteristics and, consequently, have a great influence on the process stability.
SDOF modeling of the turning process including tool wear Two approaches are possible to extend this work to multi DoF systems, one is to find the dominant mode of a mDoF system and use its parameters as the equivalent properties of the sDoF system.
Transactions of American Society of Mechanical Engineers 1958; 80:1079
Proceeding, Institution of Mechanical Engineers 1946, 154:261

Tianjin University has done a lot of experimental study on flow law of fluid in the filter chamber of rotating disk dynamic filter[15]; in 1996, by theoretical analysis of flow mechanism of fluid in the filter chamber, mathematical model of fluid flow was established and tested via experiments; the theoretical calculation method was obtained, and factors influencing filtration rate of dynamic filter was studied via dynamic test.
Factors influencing filter efficiency are numerous, but under the condition of fixed filter medium, what influences filter efficiency most are rotational speed of rotating disk, distance between blade and filtering surface and radius size of disk, which directly affect forming condition of filter cake.
Main factors influencing filtration rate is roughly analyzed via orthogonal test, dynamic pressure influence coefficient is determined via comparative test between dynamic pressure cross-flow filtration and normal cross-flow filtration, and the curve is made; 6) Make a research on several factors influencing dynamic pressure cross-flow filtration rate, including rotational speed of inner rotating cylinder, width of annular space, material concentration, filter medium and so on, find influence law of these factors on dynamic pressure cross-flow filtration rate, make objective analysis of influence degree of all influencing factors on filtration rate, and it will test and be tested by theoretical analysis.
Discussion about Material Property, Separation Method and Operation Condition.
Influencing Factors and Amplification Law of Filtration Velocity of Dynamic Rotating Filter Press (2).

Viscoelastic and Flow Properties of the Dough with RS During Proofing.
The structural changes of dough that occurred during proofing at 25°C were decisive factors for bubble formation and stability and the final baked texture (Shelke, 1990[17]; Duggan, 2008[18]).
Muffins with resistant starch: Baking performance in relation to the rheological properties of the batter, J.
Effect of microencapsulation and resistant starch on the probiotic survival and sensory properties of synbiotic ice cream, J.
Effect of resistant starch on the water binding properties of imitation cheese,J.

It shows that the slenderness ratios in the tests have little effect on the mechanical properties of models. 3) The stiffness of skeleton curve for the specimen GH-6-200 (n=0) is very small, and there is no obvious yield point on the curve.
Now take the lateral displacement of the pier top which is obtained at the time the steel pipe reach the initial yield as the yield displacement, and take the maximum displacement of each specimen as the limit displacement, Tab. 2 shows the ductility factor of specimens except specimen GH-6-200.
In addition the yield displacement of each specimen is affected by the results of strain measurement, adhesive position of strain gauge, the interval of strain sampling and measurement error and other factors, so there must be some errors.
Despite the above errors, in general, the displacement ductility factor of concrete-filled steel bridge pier is larger.
Fig. 6 Stiffness degradation are compared Tab. 2 Ductility analysis Name of specimens Yield displacement δy（mm） Limit displacement δu（mm） Ductility factor μ GH-10-280 23 180 7.83 GH-10-200 20 156 7.8 GH-6-280 19 210 11.1 3.

Most researches of ultra-precision machining would focus on a particular aspects of the technology, and seldom link up the different length scales which all affect the quality of machined surface at the micro and nano levels.
Microplasticity Model Microplasticity Model Dynamic Model Dynamic Model Surface Topography Model Surface Topography Model Input Layer Model Layer Output Layer Surface topography and surface roughness Patterns of variation of the shear angle Relative displacement between tool and workpiece Periodicity of the variation of the cutting forces Predicted patterns and power spectrum of micro-cutting force variation Predicted friction angle for the cutting force model Materials properties (e.g. shear strain and stress, etc.)
Based on the crystal plasticity, the shear angle can be inferred from the value of the Taylor factor for a given crystallographic orientation.
It also helps to explain quantitatively the additional roughness caused by the variation of the crystallographic properties of the workpiece, and leads us to a better understanding of the further improvement of the performance of ultra-precision machines.
"A Dynamic Surface Topography Model for the Prediction of Nano-surface Generation in Ultra-precision Machining," International Journal of Mechanical Sciences, Vol. 43, No. 4, p.961 (2001)

The swelling potential is influenced by factors such as clay mineral composition, dry density, void ratio, cementation, and soil macrostructure.
Particle size curve The geotechnical properties of the soil materials are presented in Table 2.
Assadi-Langroudi, Structure-based hydro-mechanical properties of sand-bentonite composites, Engineering Geology, Vol. 235, (2018) 53-63, ISSN 0013-7952, https://doi.org/10.1016/j.enggeo.2018.02.002
Sabtan, Geotechnical properties of expansive clay in Tabuk, S.
Bentley, Shrinkage and Swelling Characteristics, in Soil Properties and their Correlations.

The grain size has a strong influence on the mechanical material properties.
Metallic parts with a severe nanocrystalline grain refinement in the near-surface area show many beneficial properties.
Such surface layers considerably influence the friction and wear characteristics of the workpiece in a subsequent usage as design elements working under tribological loads due to their extreme superplastic properties.
Introduction Nanocrystalline grains within the surface layers of metallic materials show beneficial properties such as combination of high strength and ductility, resistance to corrosion and high temperatures, improved fatigue behavior and extreme superplasticity [1].
L is the length of the test-line, z the number of lines, nk the number of intercepts the line makes at the grain boundaries and V the magnification factor of the micrograph. 25 test-lines each with a length of 10 µm are applied for the microstructural analysis.