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The grain size distribution was determined by the mean linear intercept method with the number of cuts of about 300.
It is found that some of the elongated grain boundaries have large misorientation angles.
The observed cross divisions of the elongated grains are characterised by low misorientation angles, nevertheless they contribute to the calculated mean grain/subgrain size of 545 nm (Fig. 7).
After 8 passes of I-ECAP, more grains with higher misorientation angles (Fig. 6b) are observed while the mean grain size is reduced to 453 nm (Fig. 7).
Microstructure of Al 1070 plates subjected to I-ECAP: a) elongated grains after 4 passes, b) elongated grains after 8 passes Fig. 7.

Duplex or heterogeneous structure can be martensite and ferrite, austenite and ferrite or different grain size microstructure.
The space for the every indenter is 10μm and the indent number is 225 altogether.
Grain refinement is a popular strengthen method for the steels[19-21].
A grain-size-dependent structure evolution in gradient-structured(GS) Ni under tension. 2020, Nano Materials Science, 2(01):42-52
Grain refinement in the coarse-grained region of the heat-affected zone in low-carbon high-strength microalloyed steels.2010, International Journal of Minerals Metallurgy & Materials, 6:737-741

Experiments show that the Ni-based WC alloy laser cladding treatment on Q345 steel surface have a great upgrade on grain refinement, surface hardness and wear-resistance of Q345 steel surface.
(2)The cladding materials Select the Ni60A self fluxing alloy powder as the main raw material for the preparation of cladding layer, grain size is -200 mesh, the hardness is 54~63HRC.
Around the WC hard phase, dissolved a large number of Fe, Cr, Ni and other metal elements, they make a role of cementation to the WC hard phase.
(a)Q345 substrate (b) Ni60A+WC coating Fig.4 Micro-morphology of wear scar at surfaces of Ni60A+WC and substrate Conclusions (1) As the cladding material is 70%Ni60A+30%WC, cladding layer’s grain is refined, the microstructure of laser cladding composed of γ dendritic, interdendritic eutectics and WC hard phase

Coarse-Grained Capacity Balancing Model Based on Fuzzy Capacity Fuzzy Capacity Balancing Model with Penalty Coefficients.
Fine-Grained Capacity Balancing Model The fine-capacity balancing model is the foundation of the medium-grained capacity balancing model, provides process parameter data accurate to the machine precisely.
We give a heuristic adjustment algorithm based on the dynamic critical process for this model; the algorithm thought is to remove the product number (task) whose difference between the load and capacity not balanced is the closest in each circulation, to guarantee the balance objectives to be most superior.
Step4 Selecting the task number whose time took is most approach to the difference which machine's load surpasses the capacity of machine m to enter the adjustment set (balancing capacity).
Otherwise ②Choosing the machine km with sub-high load ratio, until determined the task number whose time took is most approach to the difference which machine's load surpass the capacity of machine km to enter the adjustment set.

Homogenous deformation would ensure uniform strain distribution and provide uniform grain refinement across the workpiece.
The number of finite elements is plotted over a range of strains.
The number of finite elements is plotted over a range of strains in Figure 3c.
Strain homogeneity in a work piece after ECAP was quantified as strain variance and represented by plotting histograms (number of elements along a strain range).
Mishra et al., TMS, Warrendale, Pennsylvania, 2000 [7] "Ultrafine Grained Materials-II," Proceedings of a symposium at the 2002 TMS Annual Meeting, Seattle WA, Ed.

Size effects such as specimen dimension, blank thickness, punch corner dimension, grain size, and grid dimension (for strain measurement), as well as the microstructure of material and surface condition all seriously influence the forming of miniature parts.
Raulea [8] studied the relations between flow stress and the ratio of thickness to grain size by using uni-axial tension and simple bending tests.
The results showed that yield strength decreases with a decreasing number of grains over the thickness up to one grain over the thickness; however, for grain sizes larger than the specimen thickness, the yield strength tends to increase with the increasing grain size.
T., Grain and specimen size effects in processing metal sheets," Advanced Technology of Plasticity, Proc. 6th ICTP, Nuremberg, Germany.

Often to increase the strength of deformable metal should be given reduced grain structure, up to subultra and even nano-level.
There are several ways to obtain sub-ultra-fine-grain structure of metals, and one of those ways is a method of severe plastic deformation (SPD), implemented in the whole volume of the deformable metal.
Introduction In recent years a number of new processes of metal forming to obtain metal with sub-ultra-fine-grain structure were developed.
And the only rational choice of mode of deformation for a given the profile and size of the workpiece, and consideration of all factors will make this complex process and end up getting a metal with sub-ultra-fine grain.

In the case of continuous casting structure, it consists of many enormous and coarse grains and includes many porosities and defects.
Fig. 1 Specimen sampling from a real continuous casting slab & numbering Table 1 Chemical composition of material (unit: weight%) C Si Mn P S 0.0908 0.0256 0.0132 0.0011 0.004 There are many surface defects at the surface layer of the real continuous casting slab.
This result shows that continuous casting structures have a complicate arrangement of coarse grains so that longitudinal wave is affected by the state of internal structure of materials during propagation.
One reason is that a continuous casting slab which is composed of enormous coarse grains was divided arbitrarily in the direction of thickness for testing convenience.
horizontal line defect Conclusions Transmission tests were performed with longitudinal wave and Rayleigh wave on specimens of continuous casting slab whose structures consists of enormous and coarse grains and intricate microstructures.

From Fig. 1(a), we can see that the FC specimen that was applied with solution treatment at 823K and furnace-cooled to 293K has large precipitates of μm size formed uniformly throughout the grains EDX analysis revealed these precipitates were of phosphorus habit.
That is to say that, according to the TEM observation results [10], in the grains, precipitates of average size 15nm were uniformly formed, while areas without precipitates are created around the grain boundaries, and on the boundaries large Si precipitates of average size 170nm formed, since some of the fracture surfaces indicated grain boundary fracture, it may be assumed that the precipitates on the grain boundaries triggered the fractures, and thus the increase of the breaking elongation was much less.
Fig.2 Relations between stress (σ) and number of cycles to failure (N) for the Al-1.2%Si specimens；● zincate treated or ○ not zincate treated after furnace-cooling.
Fig.3 Relations between stress (σ) and number of cycles to failure (N) for the Al-1.2%Si specimens; ● plated or ○ not plated after aging.
Fig.4 Relations between stress (σ) and number of cycles to failure (N) for the Al-1.2%Si specimens; ● plated or ○ not plated after furnace-cooling.

When x=0.005, the average grain size is 1-2μm, and the grain size increases with increasing Li+ content; when x=0.03, the macro-domains can be seen, which is important to the high electric properties.
When x=0.005, the average grain size is 1-2μm, and the grain size decreases rapidly with increasing La3+ content.
When x>0.01, the grain size is below 1μm.
Accordingly, larger numbers of nanosized polar regions(2-50nm) induced relaxor characteristics in La-modified KNN ceramics.
Thus large numbers of micro-domains induced relaxor characteristics. 3.