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Titanium is one of the most effective grain refinement elements in aluminium alloy.
For the practice condition, the number of abrasives is n, Therefore: Eq. 13 can be rewritten as 2 2 2 S np kaW σ = (ka is the functions about abrasive shape and plastic deformation angle ϕ).
Ti is one of the most effective grain refinement elements of aluminium alloy.
When the experimental eutectic Al-Si-Ti piston alloy are made by the electrolytic low-titanium Al-based alloys, the distribution of titanium in alloys is very homogeneous under the stirring of the magnetic field during electrolytic process, and a number of TiAl3 particles could be precipitated from melt during solidification of billet, and α-Al grains can easily nucleate on the TiAl3 particles (Fig. 4), therefore the microstructures can be refined remarkably.
Grain refinement effect and refinement mechanism of the industrial electrolyzed Al-based alloy and the alloy's application.

Depending on the quality and number of components, the strength limit for uniaxial compression of concrete varies in a wide range.
In this regard, the main goal of this work was to study the influence of temperature-strain parameters during hot deformation in the austenitic region and post-deformation cooling on the processes of ferrite grain formation and crushing of pearlite banding.
A study of the microstructure of the resulting rolled products showed that with an increase in the number of deformation cycles, the sizes of grains and subgrains of ferrite, as well as pearlite banding in the finished sheets, decrease.
This is necessary for more complete preservation of the polygonized austenite structure by the beginning of g®a transformation, on the basis of which more numerous and smaller ferrite nuclei appear than in recrystallized (coarse-grained) austenite.
A temperature-strain regime for hot deformation of low-carbon microalloyed steels has been developed, which is characterized by an increased number of hot deformation cycles, which stabilizes the austenite substructure and contributes to the refinement of ferrite grains and an increase in mechanical properties: strength by 50...70 MPa and stabilization of plasticity and toughness in the finished products. sheets.

The grain size distributions revealed that the aggregate on SM and M mortars is mainly between 0.16 and 1.25 mm.
According petrography the siliceous and calcitic grains present a sub-rolled morphology, suggesting a marine or river origin of the aggregates.
(a) Microcrak fulfilled with calcium carbonate crystals; (b) Microcline grain very altered; (c) General aspect of the mortar showing polycrystalline quartz grains, a big lime lump and recrystallized neoformation products inside microcracks; (d) Cavities with calcium carbonate recrystallized.
(a) Irregular porosity in the mortar paste; (b) Irregular dispersed porosity; (c) Deformed quartz; (d) Grain of basalt; The porosity type and extent could play an important role in mortars deterioration resistance; namely if there is a large number of isolated pores the water absorption of the mortar is low.
The binder is, as expected, strongly carbonated, with a large number of pores, with irregular size and shape, generally with recrystallized calcium carbonate crystals.

With the increase of hydrogen content, the number of twins is increased.
Table2 Hydrogen contents of electron beam welded joints Number velocity of flow (L/min) Time of hydrogencharging（s） Hydrogen contents (ppm) 1 0.5 5 280 2 1 5 540 3 1 6 710 4 1 10 1010 5 1 20 2550 hydrogen content/ppm FZ HAZ anear HAZ BM Fig.1 Hydrogen distributions of welded joint Hydrogen distributions of different zones in the electron beam welded joint were shown in Figure 1, and “anear HAZ” refers to the area of base metal which close with HAZ.
With the increase of hydrogen content, the number of twins is increased.
Twins in base metal generated in the interior of the grains belong to terminate-type annealing twins (shown in Figure 4a) and twins in fusion zone generated throughout the whole grains belong to penetrate-type annealing twins (shown in Figure 4b).
With the increase of hydrogen content, the number of twins is increased.

Therefore, activation of non-basal slip systems is important for Mg and Mg alloys to show good ductility since main slip system of Mg is a basal slip whose independent slip number is only two.
Grain size of the specimens was about 60 µm.
The frequency is percentage of number of grains with non-basal slip lines in observed grains at specimen surface.
Thus, non-basal slips were activated due to stress concentration at grain boundaries by activation of BS during the initial deformation stage just after yield, as shown in Fig.7.
Therefore, in Mg-0.9at%Y alloy polycrystals, FPCS may be activated due to the stress concentration at grain boundaries by activation of BS just after yield.

RE is based on obtaining a geometric CAD model from a number of 3D points obtained by scanning and digitizing an existing part or model. – The physical-to-digital process – [7-10].
The main problem of this process is the need to protect the machine from the abrasive sand grains produced during machining.
The grain size between 300-400 µm can be collected with an industrial vacuum cleaner, but the grains smaller than 100 µm are volatile and settle in any part of the machine.
• It is necessary to protect the machine from abrasive grains.
The use of an industrial vacuum cleaner can be a feasible option, but grains smaller than 100µm are volatile and can be placed anywhere on the machine

The purpose of adding alloying elements mainly is to enhance the hardenability of the material, refine grain, strengthen ferrite, improve the carburized behavior and reduce the overheating sensitivity of steel.
The grain size number of new carburizied steel and 18Cr2Ni4WA steel are basically the same, which is 8~9, and there is no grain growth after carburized treatment.
The grain size number of new carburized steel and 18Cr2Ni4WA steel are both 8~9,without grain growth after carburizing treatment.The gear entities made of new carburized steel meet the technical requirements of heavy duty carburized gear.

The as-cast microstructure of the starting alloy with a typical grain structure is shown in Fig. 1.
The La0.7Mg0.3Al0.3Mn0.4Co0.5Ni3.8 alloy is composed mainly of the matrix phase and two phases in the grain boundaries.
Phase Analyzed composition (at.%) N* La Pr Mg Al Mn Co Ni Matrix 15.4±0.6 - <1 3.6±0.3 3.6±0.6 8.3±0.5 68.4±1.2 5 Gray 8.2±0.3 - 10.9±0.2 2.9±0.4 9.5±1.8 7.6±0.1 60.9±1.7 2 Dark <1 - 1.8±0.2 9.5±0.4 15.1±0.1 16.2±0.3 56.8±0.2 3 * Number of independent measurements from the matrix phase.
This manually crushed material exhibits a wide size range of facetted grains, characteristic of this kind of milling.
Fine grains as small as 5 μm and, also, coarse grains as large as 50 μm can be easily observed in this mechanically crushed material.

Grain size measurements are reported as an average intercept distance.
On the grain boundaries large numbers of dimples were found.
The microstructures are the equiaxed grains of vanadium-base solid solution, and the grain size does not evidently change.
At low strain rate the large numbers of dimples are observed on the fracture surface.
The second phase particles are distributed in grains, and gather on the crystal boundary.

MeF4M metallographic microscope and image analysis system were used to analyze the structure, grain size, non-metallic inclusions and weld joint structure of the pipe body according to GB/T 13298-2015, GB/T 6394-2002, GB/T 10561-2005.
As shown in Fig. 4, ferrite + pearlite (F+P) in tubular structure, grain size is 8.0; Fig. 5 the weld microstructure is nucleated acicular ferrite + granular bainite + widmanstatten structure (IAF+B+WF+PF); As Fig.6 shown the microstructure of fusion zone is granular bainite + widmanstatten structure + poly-ferrite + pearlite (B+WF+PF+P); and Fig. 7 is the fine grained region structure is ferrite + pearlite (F+P).
The results show that, compared with the pipe body, there are a large number of widmanstatten structures in the weld seam and the weld fusion area of the grith weld, and the grain size is large.
Fig. 4 Tube structure Fig. 5 Weld structure near 12 o 'clock Fig. 6 Microstructure of fusion zone near 12 o'clock Fig. 7 Fine grained region near 12 o'clock Fig. 8 Macro morphology of welded joint Analysis of Transport Media.
As macroscopic analysis shows that there are a large number of oxide skins on the inner surface of the welding joint, and the residual height of the welding seam is quite different.