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The large numbers of bolt holes cut into truck frame side members act as joineries and points of attachments for various sub systems of the truck.
The number of bolt holes cut into the frame rail sections normally act as joineries and points of attachments for various sub systems.
The sub-surface microstructure (fig.5b) in hoop-radial direction of drilled holes reveals that there are significant grain size modifications in the hoop direction.
The sub-surface microstructure of punched hole (fig.5d) shows deformation in grain size up to a depth of 0.7mm from the hole surface.
This improvement in fatigue life of bolt hole surface locally, has significant influence on overall fatigue behavior of automotive frame rail structures having large number of bolt holes.

A photon energy of 12 keV was selected to maximize the number of observable diffraction peaks in the 2θ window and to ensure that the photon energy was sufficiently high above the K edges for iron to minimize the K fluorescence contribution from the specimen.
a b c d a b c d Fig.6 Observed images of hypereutectoid carbon steel by LSCM, in continuous cooling process showing that second phases nucleated and grew at triple points and grain boundaries.
The grain boundary and triple point could be observed.
In the continuous cooling process, it was observed that the second phases nucleated and grew at triple points and grain boundaries, as showed in Figure 6.
In the further cooling process, the packets, blocks and laths suddenly appeared within the grain.

Although grain disturbance around the knots in the timber may be visible, the selected specimens are smooth grained with a medium to fine texture.
In order to reconcile all these factors the study has been developed above all with non destructive tests, and only occasionally, with analyses of tension and compression along the grain.
The study has been structured both in terms of old timber [6] and new raw material (Fig.4), taking into account the fact that the protected status of this timber (Decreto autonómico 12/87, de 3-2-87, Protección de la Sabina Albar), means that carrying out campaigns with large numbers of samples is complex, due to the fact this would involve the felling of many specimens (in this case only in specific cases under the strict supervision of a specialist forestry surveyor).
The second, an ultrasonic waves test, where a straight line pulse is emitted parallel to the grain, defined the density performances of 60 samples of juniper timber.
Finally mechanical tests were used for the analysis of compression/bending along the grain according to UNE 56528:1978 guidelines.

Studying the microstructures in high resolution it was observed that the grain shape (roundness) is modified by cooling rate.
Decreasing of leaser beam speed the roundness of the solidified grain increase and the quantity of fine dispersed austenite island (light ) inside of grains ferritic (darken) matrix increase (Fig. 5).
Austenite appears on grain boundaries and inside of grains as islands in ferritic matrix.
At each samples ten number of image from characteristic weld metals were analyzed.

Acknowledgements This study is supported by“12th Five-Year Plan” to Support Science and Technology Project (Grant No. 2012BAB04B02) and the special fund for sediment research of IWHR under grant number SE1414 and SE1340 respectively.
McCave, Erosion, transport and deposition of fine-grained marine sediments, in: Fine-Grained Sediments: deep WaterProcesses and Facies, edited by D.A.V.
Lick, the flocculation of fine-grained sediments in estuarine waters, Journal of Geophysical Research (1989) 8323-8330
[11] W. van Leussen, estuarine macroflocs and their role in fine-grained sediment transport.
Dyer and W. van Leussen, the in-situ determination of the settling velocities of suspended fine-grained sediment – a review.

This suggested that at lower draw ratios unstable crystalline state strain-induced to be more stable, and the population of γ-crystal reduced which made the average grain size increased.
With the increase of draw ratio the strain was so high that rebuild grains were destroyed and made the grain size decrease.
As a result of strain-induced crystal structure neater and closer, a number of fractures in the larger crystal defect phases leaded to the decrease of grain size.
But higher draw ratios made the crystal area suffer a certain destruction, so that grain size increased slightly again.

Introduction Over the past two decades was developed a large number of methods of processing by pressure, allowing to obtain workpieces with ultra-fine grained structure, which are based on the principles of realization shear or alternating deformation.
Horita, Grain refinement and high strain rate superplasticity in alumunium 2024 alloy processed by high-pressure torsion, Mater.
Langdon, Principles of equal-channel angular pressing as a processing tool for grain refinement, Prog.
Panin, Theoretical studies of the joint “extrusion-rolling” process aimed at making sub-ultra fine - grained structure metal, 20th Anniversary International Conference on Metallurgy and Materials (Metal 2011), May 18-20.2011, Brno, Czech Republic, 272-277
Volokitina, The Role of Preliminary Heat Treatment in the Formation of Ultrafine-Grained Structure in the Implementation of the Combined Process "Rolling - Equal Channel Angular Pressing", Mater.

Room temperature ductility can be considerably improved by grain refinement and texture control [1], but press forming at room temperature still has not been achieved in magnesium alloy sheets.
Although the clad metal exhibits a mixed microstructure with fine and coarse equiaxed grains in the AZ31 layer, the grain size as a whole is smaller than that of the AZ31 alloy before roll-bonding.
This indicates that recrystallized grains were newly formed in a deformed matrix during annealing after warm Fig. 1 Optical micrographs in longitudinal section for (a) AZ31 alloy sheet before roll-bonding and (b) AZ31 layer in AZ31/Ti clad sheet after warm roll-bonding and annealing.
(a) (b) ND RD roll-bonding, in view of the fact that an AZ31 single sheet warm rolled to the same reduction as warm roll-bonding had a deformed microstructure including a number of deformation twins.
This orientation is generally observed in titanium sheets cold rolled and subsequently annealed for a short time at a relatively low temperature where remarkable grain growth does not occur [6].

Ferrite grain size is calculated by using Image-pro plus software.
The ferrite grain size and the volume fraction of martensite in DP1000 dual phase steel are shown in Table 3.
Fig. 1 The morphologies of DP1000 dual phase steel Table 3 The ferrite grain size and the volume fraction of martensite in DP1000 dual phase steel dual phase steel ferrite grain size d /μm volume fraction of martensite Vm /% DP1000 measured value 3.05 3.17 3.09 56.4 57.3 55.2 average value 3.10 56.3 XRD analysis result of DP1000 dual phase steel is shown in Fig. 2.
The plastic deformation of ferrite makes a large number of dislocations move, due to the different behavior of ferrite and martensite, which has a serious incompatibility.
In this study, the constitutive model is modified by considering the aspect of ferrite grain size.

In recent years, along with the speeding up of the urbanization, the city Hohhot, great changes have taken place, at the same time also produces a large number of construction wastes.
This shows that there are a large number of pores in the powder particles.
The average particle size of renewable micro powder is 31.1µm, and contains a large number of particles the original diameter less than 10 µm.
The grain size distribution of fine aggregate shows the size particles collocation of the fine aggregate.
Regeneration fine aggregate of grain size distribution and fineness modulus should comply with the GB/T14684-2001 rules.