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Grain structure of Alloy 625, (b).
Grain structure of Sanicro 28.
In Sanicro 28, however, dense deformation twins and less dislocation (about 200000 observation number) can be observed.
The black lines are high angle grain boundary; the red lines are S3 twin boundary and the white ones are low angle grain boundary, (a).
Deformation twins appear only in some grains.

In particular, ECAP treatment results in a submicron structure that can be homogeneous or heterogeneous depending on the number of passes through the die [1].
From these orientation maps, parameters like aspect ratio, inclination of the grain long axis, grain size and misorientation distribution have been obtained.
Sample 1, the lower inner aluminium diameter-2.5mm-, showed the highest elongated Cu grains whereas sample 3, the highest inner aluminium diameter -8mm-, produced the lowest elongated copper grains.
Samples 1 and 3 produced more homogeneous copper microstructure, the latter with highly irregularly deformed grains.
Highly elongated Cu grains can be observed near Cu-Al and Cu-die interfaces whereas the grains in the central area resulted less deformed, indicating lower stress in the latter zone.

A large number of single pulse deposits deposited and superimposed continuously and then deposition layers with a certain thickness were formed.
The epitaxial growth coating with columnar grains was then achieved by the micro-arc spark deposition.
Results and discussion The ASD coating is composed of a large number of single pulse deposits which were superimposing continuously.
Columnar grains with almost the same orientation were obtained at a higher temperature gradient.
The columnar grain dendrite passed through sublayers and grew continuously.

In case of nickel, it had been used since many decades for preparing ultrafine-grained (UFG) samples with grain sizes in the sub-micrometer range [1,2], before having been optimised to reduce the grain size further down to the nanoscale below 100 nm [3-9].
The dispersion of the ceramic nanoparticles then causes further hardening and reinforcement not only directly, but also indirectly by reducing the matrix grain size from about 300 nm in pure Ni to about 100 nm or less in the resulting nanocomposites, combined with enhanced stability against grain growth [9,12].
To obtain such information, we have recently started a temperature-dependent mechanical spectroscopy study, which has revealed a number of interesting phenomena such as low-temperature loss peaks, a wide “exponential” damping background, changes in Young’s modulus, and amplitude-dependent magnetomechanical effects (see [15] for a first overview).
The numbers on the curves indicate the maximum temperatures of the preceding, linear heating runs with 2 K/min.
The suppression of grain growth in Ni/Al2O3 is also confirmed by the stabilisation of the damping background (generally known to depend on grain size [18,20]) between 350 and 650 K in Fig. 4b.

Furthermore, the total number of drilled holes with brazed and electroplated trepanningtool is 130 and 7, which means a boost of 18.6 times in the life of monolayer brazed diamond trepanningtool than in that of electroplated one.
The number of drilling holes and the mean drilling time for single hole for brazed trepanningtool with optimum and random grain distribution is 157 and 130, and 19s and 30s, respectively.
Journal Title and Volume Number (to be inserted by the publisher) 75 a.
Table 5 Tangential force of grinding cup wheels [N] Grinding depth [mm] Grinding cup wheel 0.02 0.06 0.1 0.2 0.3 Multilayer sintered 13 24 38 142 Unable to machine Brazed with random grain distribution 7 13 20 72 106 Brazed with optimum grain distribution 5 9 12 34 80 Journal Title and Volume Number (to be inserted by the publisher) 77 The testing results show that the grinding force of monolayer brazed grinding cup wheel is obviously lower than that of multilayer sintered ones and indicate the former has assuredly very good sharpness.
The grinding force of brazed grinding cup wheel with optimum grain distribution is evidently lower than that of brazed ones with random grain distribution, which shows a best state for grinding cup wheel with optimum grain distribution in machining.

The grain size for this layer is about 5~65 nm with an average value of 16nm.
The SAED pattern shows approximatively random misorientations among these grains.
At about 40µm deep from the top surface, A large number of DLs and Dislocation tangles (DTs) are formed surrounding cementite particles as a consequent of strain incompatibility between adjacent two phases, as shown in Fig.1c.
Above results suggest that that the grain refinement occurs in the ferrite and cementite phases.
The average grain size in the ferrite phase is about 80-100 nm, some grain boundaries are visible and sharp, but there still have some DDWs and subboundaries having not developed into boundaries.

The average grain size in the streaked region is about 50 µm, while the grain size away from the streak is 80 µm.
For example, if there is locally a high density of intermetallic particles in the extruded surface, a large number of etching pits would be produced which will influence the appearance of the surface after anodising.
However, if grain boundary attack is pronounced, the grain boundary grooves may become a major surface defect.
The reflectivity of the surface is reduced by the presence of a smaller grain size and deeper grain boundary grooves.
Therefore, a small grain size band may result in a dull streak.

The structure of these composites was compact; a TiN phase was uniformly distributed between cBN grains.
The hardness of the investigated samples was dependent on the volume and grain size of the binding phase.
Their unique properties are rrelated to grain sizes of a few nanometers.
With small grain sizes, an appreciable fraction of the atoms reside in grain boundaries, i.e. atoms are situated in defect environments [4].
The VCS algorithm is one of the most powerful tools for calculating chemical equilibria especially for systems with a large number of condensed phases.

The present study evaluated the mechanical properties in compression parallel to grain of five pieces of wood from the roof structure of a residence undergo the fire in the rural area of Itapeva/SP.
Temperature (oC) Fig. 1 Strength in compression parallel to the grain.
Fig. 2 Different profiles of specimens obtained for parallel compression to grain test.
Because of it is a case study, we indicate the continuation of researches in this investigation line with a larger number of specimens, and also with other wood species, in a laboratory with continuous control of the experiment, as well as the chemical and thermal gravimetric analysis of wood after the same suffers a high temperature test.
Zhao: Compression strength and modulus of elasticity parallel to grain of oak wood at ultra-low and high temperatures.

The failure requires necessarily local plastic strains where the number of cy-cles until fracture will be the lower the higher the plastic strain amplitude is ("low-cycle-fatigue").
S355 (220 HV) HAZ - fine grain S355 (220 HV) HAZ - coarse grain S355 (350 HV) HAZ - coarse grain S355 (350 HV) V-weld specimen local temperature Profile simulation specimen controlled resistance heating measurement homogeneous grain structure and hardness Base material S355 (180 HV) Base material S355 (180 HV) Base material S355 (180 HV) Base material S355 (180 HV) III Weld seam HAZ ∆UTh Weld seam HAZ ∆UTh T1 t Ac3 T2 T1 t Ac3 T1 t Ac3 T2T2 HAZ - fine grain S355 (220 HV) HAZ - fine grain S355 (220 HV) HAZ - fine grain S355 (220 HV) HAZ - fine grain S355 (220 HV) HAZ - coarse grain S355 (350 HV) HAZ - coarse grain S355 (350 HV) HAZ - coarse grain S355 (350 HV) HAZ - coarse grain S355 (350 HV) V-weld specimen local temperature Profile simulation specimen controlled resistance heating measurement homogeneous grain structure and hardness Figure 6: Welding simulation procedure [7,8] had been measured during
The calculated (NCM) and the observed (NC) remaining number of cycles are both referred to the number of cycles until crack initation.
Base material (left), simulated fine grain (220 HV, right) [7,9].
The method is not yet working with the same quality without any dependency on the grain structure.