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Fig.1 True stress-strain curves of Al-Cu-Li-Mg alloy during hot compression (a)ε�=0.001s -1, (b)ε�=0.01s -1 , (c)ε�=0.1s -1, (d)ε�=1.0s -1, (e)ε�=10.0s -1 A number of evidences[5-7] about the high temperature deformation and conventional hot-working processes of different metals and materials suggested that the power law and the exponential relationship correlate strain rate ε� with steady state flow stress σ of the materials at low and high stress levels as follows,respectively low stress: ε�=A1σn1 (1) high stress: ε�=A2exp(βσ) (2) where n1 and β are temperature-independent constants.When investigating the experimental stress-strain relationship of steel under quick tension,Zener and Hollomon found a parameter of so-called "temperature-compensated strain rate",i.e.Z parameter,correlating flow stress to deformation variables as Z=A[sinh(ασ)]n =ε�exp(� H/RT) (3) Where A is structural
Although the original fibrous nature can still be identified,the small recrystallized grains can be seen to be present during hot deformation of Al-Cu-Li-Mg-Ag alloy at the high deformation temperature and low strain rate(Fig.3(b,c and d)),which indicates that dynamic recrystallization occurred at these conditions.
� 4(c)).Fig.4(d) shows dynamically recrystallized grains,where the strain rate Fig.4 TEM image of of Al-Cu-Li-Mg alloy under different hot deformation (a) 400� /10s -1 � (b) 440� /1s -1� (c) 480� /1s -1� (d) 480� /0.1s -1 is 0.1s -1 and temperature is 480
Since the stacking fault energy of aluminium can be lowered by addition of the most soluble elements such as Mg,Ag and Li,the increased stacking fault width in such alloys impedes dislocation mobility, thus modifying the balance between dislocation generation and annihilation.Consequently,the dislocation density is considerably greater and tangles of dislocation formed in that way result in high angle boundaries which initiate nucleation of recrystallization.Besides,the precipitates of T1 and Al3Zr particles decrease the mobility of dislocation,and hinder the migration of sub-boundaries and grain boundaries,thus enhance the critical strain value for dynamic recovery,and induce dynamic recrystallization.

From Fig.6, there were two size grains in the composite samples, one was about 1 ~ 2 µm and the other was approximate 5 µm.
And the small grains became less as mullite content increased.
EDS analysis revealed that the small grain was anorthite.
The high porosity foams contained a large number of defects and had higher specific surface area, so their abilities for radiating heat were better, which was the reason for thermal conductivity decreasing.

The number and dimension depend on the amount of MZ.
The reduction of Hardness in HAZ was due mainly to a partial dissolution of γ’ and only limitedly to a grain s growing.
The grains of the MZ exhibit prevalent [111] and [101] orientations thus the initial [100] orientation is no more present after solidification while HAZ maintains the original [100] orientation and only few grains of different orientation can be observed.

Facing serious bank collapse, Dragon River bank after the reservoir directly threatens a large number of immigrants’ building and residents' life and property safety.
According to field investigation and exploration, angle of the terrain slope is steep, which is 30 ~ 53°, and local is the scarp, covered with a small amount of silty clay slope and grain filling that thick is 0.3~3.6m.
According to the survey report, each layer’s physical and mechanical properties of rock mass are as follows: The reservoir bank stability calculation of Dragon river bank slip type involved in the soil can be divided into grain filling soil, silty clay and fragment stone soil.
The grain filling: it is mainly composed of sandstone stone and from loose to close.

The compositions of the coatings were determined by EDX using the ZAF (Z: atomic number effect, A: absorption effect, F: fluorescence excitation effect) correction method.
It can be seen that the grains of CrN/TiAlN coatings are all coarse and the surface of CrN/TiAlN coatings grains is rough.
Compared with Fig.4(a), the surface of CrN/TiAlN coatings is relative smooth and the roughness is reduced obviously. the grains of CrN/TiAlN coatings are very small, whose size is limited within nanometer.

This paper makes investigations on cigarette production lines and develops three kinds of new-style glue rolls: SiC chemical composite plating glue rolls, TiN ion plating glue rolls and ZrO2 ceramic glue rolls with fine grains; a friction and abrasion characteristics experiment machine tool is developed to make comparison and testing between new-style glue rolls and traditional ones.
Firstly, SiC chemical composite plating glue rolls, TiN ion plating glue rolls and ZrO2 ceramic glue rolls with fine grains have been developed successfully by using of the nano-machining technology of working surface.
Composite plating film is a special film that is formed by mixing up one or several kinds of thawless solid grains with metal plating film evenly through the method of metal electrodeposit.
The main motor in the headstock is controlled by transducer, which can carry out the Journal Title and Volume Number (to be inserted by the publisher) 193 stepless speeding control of the driving roll. 2.

As shown in Fig.4, The main crack was intergranular in coarse grained region, and ends at fine grained region of HAZ.
Lots of cracks within coarse grain zone Pre-Welding Heat Treatment The method of Pre-welding heating treatment should adopt electric heating, such as Rope-type heater boosters.
The number of inspecting positions was not less than four for welding seam an for base metal and all inspection positions should be distributed uniformly along circular.

In the past, the investigation of thermo-mechanical treatment has been focused on the effect of deformation process and aging process on microstructure during the treatment [11].Hirosawa et al. [12] studied the age-hardening and precipitation behavior of 6022Al-Mg-Si and 2091Al-Li-Cu alloys. 6022Al-Mg-Si alloy exhibitedsuppressed aging hardening or even aging softening after highpressure torsion (HPT) while 2091Al-Li-Cu alloys demonstrated significant aging hardening, which should be due to the formation of transgranular precipitation of the nanometer-scale particles within ultrafine grains.Mondal et al. [13] found several texture microstructure was formed after hot cross-rollingin 7010 (Al-Zn-Mg-Cu-Zrbased)Al alloy.
Huh et al. [14] obtained a random texture after two steps cross-rollingtreatment in AA5182 sheet, and concluded that the random texture might be related to the suppression of both the nucleation and the subsequent growth ofthe{001}<100> cube orientation.Lee et al. [15] observed the generation of the ultra-fine-grains with high angles ofmisorientation was accelerated by high temperature together with the extensivestrain imposed to the specimens during dissimilar channel angular pressing.
Nano-scale precipitates agglomeration and growth of grain size with aging temperature was found from 160 to 190ºC.However, the effect of thermo-mechanical treatment procedure on the microstructure evolution and properties has rarely been reported.
Moreover, the number and randomness in orientation were also increased after thermo-mechanical treatments.

EDX analysis (Fig. 7) shows that the depletion of Fe and enrichment of Y have occurred to the sputtered coating, and a large number of oxides mainly composed of Fe oxides are formed.
So the hot corrosion resistance of the gained fine grain materials is very undesirable for Fe-20%Y alloy sputtered coating and Fe-30%Y alloy sputtered coating.
On the contrary, the increase of the area of grain boundaries and phase boundaries owning to grain size reducion provides lots of short diffusion channels for the diffusion of Fe ion and oxygen ion, which accelerates corrosion rate of the three coatings.

The mechanism can be attributed to the occurrence of the easier process of mulitiplication of sufficient number of preexisting elements of plasticity(dislocation, twins) at higher loads, in contrast to the more difficult process of generating new dislocations in vicinity of the indents of lower loads.
The modest tensile residual stress would be generated with matrix grains and compress radial stress in second phase grain during cooling processing.
The present of tensile radial stress weakens the grain interiors[4].