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Introduction Cr12 die steels are the main materials for cold work dies in the word and a large number of researches have carried out in decades [1-3].
In addition, investigators [8] have suggested that reducing the total number of carbides larger than the critical size, and homogeneously distribution were useful ways to improve fracture toughness.
It is clear that there is large number of fine carbides precipitated in the matrix and distributed uniformly in new steel comparing with Cr12MoV steel.
There is large number of cleavage planes in impact fracture morphology of Cr12MoVsteel, while a large number of dimples in morphology of new steel.
The large size of carbide particles in materials decrease the fracture toughness in the same condition of grain size and yield stress.

With respect to the granulation of the same, an increase in the grain size of the sandstones is observed for the quartzites, due to these recrystallizations, which confers greater resistance to the compressions and the physical wear for the latter.
Historically and among all Brazilian states, that of Minas Gerais is the one with the highest number of applications for quartzites, considering the historical constructions of the 18th and 19th centuries.
With few examples of applications in the South and Northeast regions, the largest number is concentrated in the Southeast and in this case the applications in some historical cities of the state of Rio de Janeiro stand out, especially in its capital, the city of Rio de Janeiro.
The first and most common, was named Phacoidal and is characterized by the presence of porphyritic crystals of feldspar in medium to fine - grained mass.
Sanding, as well as the loss of mass observed in sandstones, quartzites and even in granite rocks, were also considered to be consequences of these detachment of single grains or aggregates of grains.

Therefore, moving the power consumption control mechanism from hardware-level to fine-grained software-level is indispensable and more promising for data centers with virtual machine environments, and has the potential to save more power consumption.
Fine-grained dynamic voltage/frequency scaling is an important tool in managing the balance between power and performance in chip-multiprocessors [20, 21].
Kim et al [22] explored the potential system-wide energy savings offered by implementing both fine-grained and per-core DVS/DFS in a 4-core CMP system.
Therefore, more power reduction can be achieved if fine grained DVS/DFS schemes are used elegantly in virtualization environments.
Due to the high-density of service consolidation and development of new applications and the increasing number of users with heterogeneous requests, providing users with QoS guarantees while executing applications and saving power consumption has become a crucial problem that needs to be addressed.

The average grain size of the alloy is 40 μm.
In addition, the formation of carbides on the grain boundaries occurs during the heat treatment.
Comparing the microstructures of the two specimens, it can be seen that there are some differences in the sizes, morphologies and number densities of the γ′ phases and carbides, which is probably due to the sampling positions from the material.
Generally, with the increase of size and number of sharp angles, the stress concentration induced by carbide and carbonitride inclusions increases, which may encourage crack initiation and growth.
This is common in superalloys because grain boundaries are weak at elevated temperature, and the carbides precipitated on the grain boundaries may also assist the propagation of intergranular cracks.

Because EDS can not respond to elements of atomic number less than10.
Fig.3 X-ray diffraction pattern of nickel-phosphorus composite Al2O3 deposits (a: room temperature b:300˚C c:50˚C d:400˚C ) It indicts that migratory ability of atoms is improved after heat treatment at 300˚C .The structure of the deposit is mixture of crystalline compound and amorphous compound .The coating has obvious crystallized at 350˚C and 400˚C , the coating has completely changed into equilibrium phase of Ni, Ni3P.The diffraction peak at 400˚C is more sharply than 350˚C .If the temperature increase further, grains will grow bigger.
Along with increasing of the heat treatment temperature, Ni3P phase grew at 450˚C , the number of electrochemical corrosion micro cells gradually drop off, which will help to improve corrosion resistance of coating.

Ordering of atoms occurs in a large number of alloys.
From the large angle convergent beam electron diffraction (LACBED) on polycrystal the continuity of lattice planes between neighbouring grains can be noticed.
The number of fringes depends mainly on the thickness of the illuminated zone and can be used to measure the specimen thickness.

Results and Discussion Fig. 3 shows the relation between number of fatigue cycle N and the fatigue crack length a and b.
It is seen from Fig. 4 (c) and (d) that the recrystallized grain size just at the crack in H2 is larger than that in pure air.
This means that APZ size with high accumulated plastic strain Fig. 3 Relation between number of cycle N and fatigue crack length on the notch root surface a and fatigue crack length on the side surface b.

Dependences of the deposition rate on the substrate temperature have been reported for a number of sputtered materials.
On the other hand the number of particles striking the cathode is proportional to the current density consequently current is much more importantly in determining the deposition rate than voltage.
The sputter-deposited Cr film shows a columnar growth of Cr films perpendicular to the steel substrate by sputtering, whereas the electroplated Cr film shows equiaxial grains.

In order to examine the parallelism of the method, use six samples material of A, B, C, D, E, F each time respectively, each sample takes 10g, take two types of different serial numbers each time, experiment six times each kind of samples respectively.
From fig.1 and table 3 .As a result of the grain size difference, causes the final rate of liveweight growth difference.
Experimental maximum deviation experiment’s degree 1 2 3 4 5 6 A maximum deviation 0.10 0.15 0.08 0.08 0.07 0.07 B maximum deviation 0.09 0.11 0.14 0.15 0.05 0.07 C maximum deviation 0.13 0.17 0.13 0.13 0.07 0.11 D maximum deviation 0.14 0.14 0.08 0.12 0.06 0.18 E maximum deviation 0.02 0.12 0.12 0.07 0.11 0.10 F maximum deviation 0.08 0.06 0.07 0.10 0.06 0.07 Table 3 Sample A, B, C, D, E, F final average weight gain Materal number 1 2 3 4 5 6 A 1.03 0.81 0.93 0.96 0.98 1.02 B 1.26 1.16 1.19 1.22 1.12 1.22 C 0.89 0.91 0.81 0.83 0.88 0.98 D 0.75 0.92 0.76 0.84 0.85 0.97 E 0.52 0.65 0.51 0.49 0.58 0.56 F 0.43 0.58 0.46 0.44 0.48 0.49 Table 4.

Yakwool fabric possesses the performance of good elasticity feel, grain lines, soft and light.
The number of knitting needles was 160-pin and all the fabrics were weft knitted fabrics.
(1) (2) Where Yi is the hand value of number i.C0, Ci1, Ci2,are constants,Mi1 and Mi2 are the average of Yi and Yi2, σi1and σi2 are the standard deviation of Yi and Yi2.