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The concrete piles reinforced with 500MPa fine-grain steel bars show good seismic performance and 500MPa fine-grain steel bars can be used in seismic design.
However, it still lacks of systemic research on the anti-seismic capability of column reinforced with the 500MPa fine-grain steel bars, which may cause inconvenience to define the design items and promote the application of the high strength steel bars. 500MPa fine-grain steel bars own high yield platform, and enable to reduce the number of steel bars appropriately, which is more economical and conducive to construction, can lessen incompact concrete which caused by too closed steel bars ,and then increase the durability of the concrete structures.
BF represents 500MPa fine-grain steel bars, B represents HRB335 steel bars and A represents HPB235 steel bars.
Conclusions Six concrete piles reinforced with 500MPa fine-grain steel bars under low cyclic reversed loading were texted and studied.
The concrete piles reinforced with 500MPa fine-grain steel bars Show good ductility and 500MPa fine-grain steel bars can be used in seismic design.

The response variables were as discussed, flow stress maximum and grain size.
The average grain size was determined based on the standard GB/T 6394-2002 and the grain grade was between 6 and 9.
Compared with the error, the strain rate almost had no influence on the grain size.
As shown in Fig. 4, the grains were almost new grains generated by DRX.
Comparing with the error, the strain rate almost had no influence on grain size.

A number of processes have been developed following this philosophy, namely equal-channel angular extrusion (ECAE), accumulative roll bonding (ARB) and multi-axial forging (MAF).
At low strains, large number of dislocations are generated, which align themselves in a low energy configuration forming low angle grain boundaries (LAGBs).
The grain size measured by EBSD was ~300 nm.
With increasing number of cycles, the yield stress as well as the ultimate tensile stregth of the material increased, however, the tensile elongation decreased.
An overall low ductility is observed, although, both uniform and total elongation is seen to increase with number of cycles.

Fig. 2(a) shows the microstructure of the as-extruded sample (N=0) showing equiaxed grains of an average grain size of (50 ±10) µm.
The final grain size at N=4 results indipendent from the starting extrusion grain dimension.
Fig.5d illustrates the hardness variation with the number of ECAP passes for the two investigated alloys.
In particular, radius number 10 always shows the lowest value.
In fact there is a progressive increases in hardness with the number of passes for the alloys up to the same values when N=4.

The model shows that any increase of static load, size of grain, work speed, number of effective dynamic abrasive particle, the amplitude and frequency of tool or any decrease of fracture toughness property and hardness will result in the increase of the MRR, and the theoretical model of the MRR is tested, meanwhile the paper draws the conclusion that the surface quality under TDUG is superior to that under common grinding, which is tested by the means of grinding of fine-crystalline ZrO2 ceramics.
of effective dynamic abrasive particle, 22K ζ= .� � � � � � � � � � � � � � � � � � � � � �According to Eq.6, any increase of static load, size of grain, work speed, number of effective dynamic abrasive particle, the amplitude and frequency of tool or any decrease of fracture toughness property and hardness will result in the increase of the MRR under TDUG.
It may be the reason that as the speed of working table increases, the friction per unit of time between workpiece and abrasion wheel increases, and the number of effective abrasive particle per unit of time improves.
From Fig.5, MRR is higher when abrasion wheel with coarse grain size is used.
But MRR is lower when abrasion wheel with fine grain size is used, but their change tends with the speed of working table are similar.

With the increase of deformation degree, the number of shear bands increased.
A few small grains about 20 μm were found in the grains about 50μm.
A large number of slip bands were found in the grains.
The small grains have been found in the grain boundaries.
A large number of recrystallized grains exists in the upper area and edge of large grains in middle area.

Lamellar grains of were observed in both materials.
The hardness evolution of NAH and PA materials with increasing number of ARB cycles is shown in Fig. 1.
This hypothesis was supported by TEM observations indicating that precipitate number density decreases with increasing number of ARB cycles [5].
In order to ascertain if pre-ageing affects the annealing response of the heavily deformed AlScZr alloy, a NAH specimen deformed by 6 ARB cycles was pre-treated at 300°C/2h to a 40 50 60 70 80 0 2 4 6 Number of ARB cycles Hardnes HV 10PA NAH 300°C/2h Fig. 1 Hardness evolution with increasing number of ARB cycles of both pre-treatment variants.
The AlScZr alloy has more than 5-times smaller grains.

This large number of rolling steps is the main reason for the high cost of magnesium sheets.
Thus, it saves a number of rolling and annealing passes in comparison to the conventional rolling process.
There are worldwide a small number of industrial or laboratory scale twin roll casters installed at universities, companies and research facilities.
Standard metallographic sample preparation techniques were employed and an etchant based on picric acid was used to reveal grains and grain boundaries [7].
The large number of dendritic grains in the upper and lower regions of the strip is an indicator for a low degree of deformation during the rolling operation.

Inside grains a very low number density of TiN and AlN particles was observed.
Microstructure consisted of small equiaxed recrystallized grains and non-recrystallized grains (angle misorientation inside these grains was greater than 2°).
Fig. 4a shows that the number of grains in the matrix with the orientation close to the Goss texture (≤ 15°) was low.
Fig. 4 Microtexture of samples after the slow heating to the 620°C, supplier A: a. grains close to the Goss orientation + high angle boundaries (θ > 15°), b. the legend for Fig. 4a In the sheets after the slow heating to the 620°C the number density of precipitates was less than that in the sheets after the DCA.
However, the number density of precipitates in the sheets during the slow heating up to 620 °C decreased.

However, the tensile fracture surface of as-extruded alloy has a large number of small dimples besides cleavage planes and tear ridges, as seen in Fig. 8 (b).
Secondly, the grain refinement makes the grain rotating and grain boundary sliding easier.
Due to the different orientation of each grain, the deformation of each grain is not at the same level.
The interaction force among adjacent grains causes the mutual rotation of the grains.
The grains were effectively refined after hot extrusion.