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The banded-grain boundaries have a similar role to strong interface in preventing dislocations slip.
Cleavage fracture has been clearly established in a number of cases in various Al alloys, such as Al-Mg, Al-Zn-Mg, Al-Li, Al-Cu.
For a given applied load and layer thickness, there exist an equilibrium number of dislocations in the pile-up and any additional dislocation emission will be prevented by the back stress once this number is reached.
Dislocation Pile-up at Grain Boundaries.
(a) (b) (a) (b) Fig. 6 Grain boundary configuration and dislocations pile-up there After sufficient annealing the grains in Al interlayer tend equiaxial and the dislocations pile-up effect at equiaxial-grain boundaries is very weak, as shown in Fig. 6 (d), which is similar to that in bulk Al metal.

Introduction Combine harvester is easy in danger of fault because of the complexity, randomness, diversity and decentralization.Failure will have an effect on the harvest quality.Moreover,present reaserch can’t fully reflect the failure of the combine harvester only aiming at the congestion fault[1~3].The multi-input predictive fault diagnosis control system on combine harvester promoted in this thesis canreflect the combine failure in a better way taking into account the grain loss,engine vibration and clogging failure.In addition, currently used for fault the fault diagnosis algorithm,he prediction algorithm[4][5]and fuzzy neural network algorithm[6][7],are always involve a large number of calculation quantity,which will lead to a horrible lag directly. with the aid of physical characteristics of the target variablea ,a prediction algorithm based on acceleration is proposed in this paper[9][10].This algorithm can improve the instantaneity of fault dignosis system.On the premise of
Fig.1 Fault diagnosis system hardware block diagram Establish the Model of Predictive Multi-Input Fault Diagnosis Control System Establish of input System.It is important to detect the vibration fault because it will lead to a loud noise and Severe damage.loss rate is also an important evaluation indicator of harvest quality.therefore,it is considered in this article to make this fault diagnosis system perfect.Once the rotate speed of threshing drum,lost grain auger and delivery slot is changing abnormally,combine harvester will fall into a blocking failure[12~15].In short, the input of fault diagnosis system includes five parts: engine vibration, grain loss,rotation speed of threshing cylinder,rotation speed of transport grain auger and rotation speed of conveyor trough.
Collecting the value of engine vibration using the vibration sensor mounted on the engine pto shaft,threshing cleaning loss by cleaning loss sensor mounted on the tail vibrating sieve scale ,threshing drum speed,lose grain auger speed and delivery slot speed.
It is inevitable to have grain loss.
Tab 1.The real-time velocity value of the working parts Input 4.5 /S 5 /S 5.5 /S 6 /S 6.5 /S 7 /S 7.5 /S 8 /S 8.5 /S 9 /S Conveyor trough （r/min） 469 468 472 468 469 470 469 468 470 469 threshing cylinder （r/min） 946 945 921 887 907 939 941 943 947 950 Transport grain auger（r/min） 999 998 996 995 996 997 998 999 997 998 Engine vibration acceleration（g） 2.51 2.31 2.01 1.89 1.97 2.18 2.23 2.27 2.39 2.51 loss rate(%) 5.5 5.4 4.9 4.7 5.2 5.3 5.4 5.5 5.6 5.5 Conclusion PLC,the core component of the intelligent system,is used to monitor the combine fault by collecting and analyzing data inescapably.This process will consume some time which lead to the bad lagging on the entire system.Therefore,a multi-input fault diagnosis predictive control system based on the acceleration is proposed by the physical characteristics of the target value.This predictive diagnosis algorithm proposed in this paper can simplify the calculation effectively without large number of complex calculations.In

These alloying elements can effect a number of precipitations at high temperatures.
It shows a σ-phase grain between a ferritic and an austenitic grain.
A special final polishment was done for EBSD-measurements by fine grain colloid silica (with 0.02 µm grain size) for at least 30 min.
ferritic island in an austenitic grain, or an austenitic grain seemed to be a complement of a ferritic phase, or a σphase grain between an austenitic and ferritic grain).
Secondly if a σ-phase grain has an adjacent ferritic grain, then they are in parent-inherited relationship, but if a σ-phase grain has an adjacent austenitic grain, then the parent-inherited relationship is not sure, because the austenitic grain can be a primary austenite.

Rolling with a large number of passes led to the formation of fairly homogeneous rolling textures at all through-thickness positions.
During subsequent annealing, recrystallization was observed to be faster in those grains with {111} orientations, while it was retarded in grains having orientations close to {001}<110>.
In these layers, grains were pancake-shaped.
The transverse section of the LRD sample comprised recrystallized grains along with some elongated grains.
Most of these elongated grains had orientations lying close to {001}<110>.

There are large numbers of small pores, and distributed uniformly.
It can be seen from Fig.7 that pores are mainly surrounded by well-grown grains, and there is no pores inside of grains basically.
There are grains which are granular or flaky around pores.
Meanwhile, because of the heat insulation of the point contact between CA6 flaky grains, the thermal conductivity of composite aggregate is lower than tabular corundum.
（3）A certain amount of CA6 generation will cause a large number of small pores appear in composite aggregate, moreover, it distributes uniformly and widely; the pores are mainly surrounded by grain boundaries, there is no pores inside of grains basically, and there are granular corundum grains and flaky CA6 grains around the pores.

Each grain contains one or more branch crystals, and grains with different orientations are separated by grain boundaries.
Samples heated five times (Fig. 2c-c') show block crystals with an increasing number of fine internal crystals.
Samples heated three times (Fig. 4b-b') exhibit isoaxial crystals containing fine internal grains.
As the number of heating cycles increases, the alloy transitions from slat dendrites (Fig. 4a-a') to isoaxial dendrites (Fig. 4b-b'), and then to thin dendrites (Fig. 4c-c' and 4d-d').
The crystals contain refined internal grains, and the number of granular compounds within the crystals increases.

Evaluation of the Coverage Pattern on the Fracture Surface of BiEmbrittled Cu Grain Boundaries by Means of Auger Electron Spectroscopy C.
In studying grain boundary segregation in Cu-Bi alloys by means of Auger electron spectroscopy samples must be broken in-situ.
A continuous coverage of Bi atoms on Cu grain boundaries occurs if the Bi-Bi bond is weaker than the Cu-Bi bond.
It is believed that the fracture of Bi-embrittled Cu grain boundaries belongs to the latter case.
The schemes of continuous and crosstie-like coverage patterns of Bi in a Cu grain boundary.

Thus, there is no cavities at grain boundaries and the relationship of the stress and the strain rate can be expressed as follows [2]: pnd RT Q Aexp −      −= σ ε& (1) where ε& is the strain rate, A the material constant, Q the apparent activation energy, R the gas constant, T the deformation absolute temperature, σ the applied stress, n the stress exponent, d the grain size, p the grain size exponent.
It also indicates that improving the diffusion on the grain boundary and/or in the grain (increasing the value of Aexp(−Q/RT) can enhance the strain rate.
The powders have good dispersion, uniform grain size and no hard agglomeration.
The as-sintered ceramics had uniform grain size.
Acknowledgements This work was supported by the National Natural Science Foundation of China under grant numbers of 50875032 and 50505005.

As the sputtering process proceeds, the number of this ions decreases and, instead, the Cr ion intensity increases.
Close to the steel surface, the Cr ions number also decreases and the Fe intensity rises, suggesting that the bulk steel was reached.
On the coated samples, only the grains of the coatings are visible.
The increasing number of Al ions can be related to segregation near the steel surface and internal oxidation of this element after the long annealing [25].
For the coated sample, the larger grains look similar, but they are much bigger in size.

Introduction Since the early 1970s，Ferroalloy plant produced a large number of Al2O3-Cr2O3 slag after extraction Cr by Al-thermal method[1].
By adding 10% 3.0-2.0mm MA grain increased the thermal shock resistance up 13 times.
But the thermal shock resistance was decreased adding 2.0-1.0mm grain and 180 mesh power.
But Al2O3 of Al2O3-Cr2O3 could occured reaction by adding 2.0-1.0mm grain and 180 mesh power MgO-Al2O3.
By adding 3.0-2.0mm grain of its decreased slowly and closed to the property of 0 sample.