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Grain distortion due to peening was observed to a depth of 410µm and was correlated with the measured residual compressive stresses.
The crack tunneling profiles were recorded in thirty three SENB specimens, which were either fatigued to failure or fatigued to a predetermined number of cycles and fractured.
Polished and etched 1.2x1.2x0.81cm slices from the as-peened and fatigued specimens were viewed in a 400X microscope to study the subsurface grain structure of the as-received and shot peened specimens.
The data for R = 0.1 shows a small increase in the number of cycles to failure with increasing shot peening intensity while the corresponding data for R = 0.8 shows no change in fatigue life due to shot peening.
Elongated and flattened grains dominated the subsurface of the peened specimen to a depth of about 410µm.

Due to its hexagonal structure of magnesium and therefore the limited number of glide systems at room temperature the deep-drawing process can only be carried out at elevated temperatures above 250 °C.
The AZ31 alloy exhibits a microstructure with distinctive grain boundaries and some precipitates in the grains.
The microstructure of the AZ31 sheet is inhomogeneous and coarse grains with circumjacent small grains are presented (Fig. 3b, Fig. 4b).
A finer and more homogeneous grain structure than the extruded sheets are observed.
Coarse grains and twins are not found.

This method has been applied to a number of systems [2,3,4] including HSS [5,6,7,8,9].
SLPS involves the formation of a liquid along the grain boundaries in powder, which leads to densification [2] Fig. 3 shows schematically the sintering window -the temperature band over which acceptable microstructures (i.e. absence of coarse grain and carbide structures and continuous grain boundary carbide films) and properties can be obtained.
For T ≥1260ºC, an acicular shaped tungsten/molybdenum rich carbide could also be seen occasionally at grain boundaries.
Coarsening of MC carbides and prior austenite grain size was observed with increasing temperature for P68.
This higher P81 distortion corresponds in the microstructure to a continuous M2C grain boundary eutectic carbide network, more extensive than in the P77 alloy.

In the SEM image, the pure iron powder grain boundaries are clearly visible.
The feature of this method is that finished surfaces are extremely smooth due to the use of grinding wheels with large grain size numbers (fine grain particles).
We studied the effects of grinding wheel oscillation during finish machining and the effects of the grain size of the grinding wheel.
Fig.11 shows the machined surfaces obtained using the grinding wheel with grain sizes #400, #800, and #1000.
The relationship between grain size and grinding wheel wearing is shown in Fig.12.

Technical requirements of the graded granular cushion construction technology on construction materials as well as component characteristics Main performance indexes of the gravels in graded granular cushion According to relevant information and regulations, the grain diameter and gradation of the mixed and stirred graded gravel should accord with the standards of the related parameters in table 1, and also proportion of the grains passing 0.075mm sieve in the fine aggregates with square hole sieve of below 0.5mm is required to less than or equal to 66%.
Table 1: The gradation parameter range of the graded gravel at the bottom Side length of square hole sieve (mm) 0.075 0.1 0.5 1.7 7.1 16 25 45 The quality percentage of side sieve (%) 0~7 0~11 7~32 13~46 41~75 67~91 82~100 100 From table 1, it can be seen that the quality percentage of side sieve is in 67%-91% if the grain diameter is larger than 16mm.
That is to say, the proportion of the broken grain in the coarse grain should be lower than 30% at least.
Then, the materials of different grain diameters are re-arranged and filled using the mechanical crushing method, and the purpose of producing the plates with a certain compactness through the friction, mutual interlocking, and cementation between grain materials is achieved.
In the mixing process, water should be intermittently sprinkled for ensuring sufficient moisture, and also the mixture should be uniform for ensuring no segregation problem appear in fine grains and a supplement mixing is needed if it appears.

Introduction High permeability grain oriented Fe-3%Si steel is characterized by sharp Goss texture which is developed in the presence of precipitates which inhibit the normal grain growth and ensure the abnormal growth of Goss grains.
The technologies of manufacturing high permeability grain oriented Fe-3%Si steel are generally classified into two groups.
The grain growth inhibiting force of randomly distributed disperse precipitates can be described by 3/2γf/r, where γis the grain boundary energy, f the volume fraction of pinning particles and r the precipitate average radius[3].
It showed that the smaller the size and the greater the number per unit area, the greater is the restraint to normal grain growth.
Copper sulfide precipitates are the primary inhibitor species in the common grain oriented (CGO) silicon steels and grain boundary pinning is effective at a mean precipitate size of 30–100nm [4].

There are a number of material states which are important in determining the response of the system.
The primary state is the number density of grains, the observable regimes varying from dense packing to dilute suspension.
In the contactual regime, the grains may either slide or roll at contact.
A granular system exhibiting "solid-like" behaviour tends to correspond to constrained environments, to states of dense packing, to a zero mean free path, to insignificant grain kinetic energy fluctuations, to grain contacts with a finite duration and to sliding or rolling at grain and boundary contact points.
There are a number of additional assumptions, for example, the grains are assumed to be smooth.

It was shown that the parameters of the strain/stress patterns are strongly affected by the number of preliminary deformation cycles.
Number of Cycles at Temperatures of Tests а) at loading, b) at the start of unloading, c ) at the end of unloading Fig.4.
Temperature and Number of Cycles: а) at loading, b) at the start of unloading, c) at the end of unloading Fig. 7.
Eggeler The influence of temperature on the evolution of functional properties during pseudoelastic cycling of ultra fine grained NiTi, Mat.
A 481-421, 2008, p.142-145 [4] A.Yawny, M.Sade, G.Eggeler, “ Pseudoelastic cycling of ultra-fine-grained NiTi shape-memory wires”.

To improve the adhesion between bitumen and aggregates and to get in general better functional characteristics of asphalt mixtures large number of available additives exists in civil engineering.
Second group includes mineral additives, which may partially or completely replaced fine-grained particles, normally in the form of filler.
In this article the objective was set to qualify effect of mechanically activated microfiller originating from limestone by-products or from recycled concrete as a substitute to fine-grained active filler in asphalt mixtures.
Aggregates are in asphalt mixtures represented in various fractions, the larger particles form the skeleton of the asphalt mixture while the fine-grained particles are having a role of an admixture and create together with the bituminous binder asphalt mortar (mastic).
The amount of filler in the asphalt mixture is specified, similarly as in the case of fine-grained and coarse-grained aggregate in a weight ratio.

The computing speed is the mark an important indicator of computer performance, the number of scales to measure the speed of computer processing; a second look at the computer can perform the operation of addition [8].
Binding energy of the nanocrystals and the free energy and the grain size is strongly dependent on the relationship.
Therefore, we can use technology appropriate doping control grain growth.
Softening of nanocrystalline metals at very small grain size.
Three dimensional simulation of grain growth in the presence of mobile pores.