Search results

With increasing suitable annealing temperature at the growing film surface, the additional energy contributed to finer and uniform grain development in the films [8, 9].
It was observed that the grains of the ZnTe ceramic films were dense and uniform with various annealing temperatures.
The grain size and uniformity of the deposited film were enhanced and depend on annealing temperature.
Large grain boundary region is highly disordered, and having large number of defect states due to incomplete atomic bonding with higher annealing temperature.
These situations are known as trap states act as effective carrier traps, impeding the flow of majority charge carriers between the grains [10].

The microstructure and cross-sectional SEM analysis revealed that the nano grains were developed and thickness decreased from 381 nm to 131 nm.
The TiAlN films have been prepared by a number of techniques including chemical vapor deposition, cathodic arc and reactive magnetron sputtering.
D = Kl/b(cosq) (1) Where D is the grain size (nm), K is Scherrer constant (0.89), l is the X-ray wavelength, b is FWHM, and q is the diffraction angle.
The nanocrystalline TiAlN were formed mainly of individual fine grain with porous and void were clearly identified from low N2 flow rate (2 sccm).
When N2 flow rates increased to 12 sccm, it was found that the surface composed of small nano grains size with less void and denser structure which due to high N atom can more react with Ti and Al atoms.

Pyrite grains with a size of 50-200 μm were selected after grinding and sieving of pyrite cubes.
Both slices and grains were cleaned and sterilized as described [7].
Chalcopyrite grains (50-200) µm were washed by 0.1 M EDTA and 0.4 M NaOH.
For cell attachment assays, 10 g of sterile pyrite or chalcopyrite grains were incubated with pyrite-grown cells of Acidianus sp.
The amount of attached cells was calculated by subtracting the planktonic cells from the initial cell number.

The production process of the component is affected by a considerable number of parameters [3], beginning with the laser power and ending with the heat treatment, which determine its final mechanical properties.
Together with scanning strategies, also the other parameters were changed (laser output, scan speed, hatch distance, number of cycles of remelting).
Thus the SLM processing of those alloys often leads to samples with high porosity or large number of cracks.
A large group of macro cracks and also cracks along grain boundaries were found.
Character of the fracture surface is similar to fracture surface of the SLM samples processed by meander strategy (i.e. presence of columnar grains and dimple like morphology) – Fig. 6.

Fatigue crack propagation rate is usually affected by the microstructure, grain size, hardness, and applied stress ratio.
Fig. 6 shows that microstructure in weld joint exhibit larger grain size than that of base metal.
When the plastic deformation region is smaller than the grain size, barrier effect of grain boundary to the fatigue crack propagation can be decreased and the crack path can be distorted [9].
Therefore, the low crack propagation rate of weld joint is thought to be caused by the coarse grain microstructures and high hardness phase.
It may be caused by the hardened microstructure and distorted fatigue crack propagation path within irregularly arrayed coarse grain in weld joint.

This treatment is patented, the patent number is: EP 1 738 859 A1.
Below this layer the base material has many larger grains.
The grains of the base material are slightly curved in one direction here too due to the mechanical machining of the cylinder bores.
The average grain sizes (dFIB) and the maximal and minimal values of grain sizes (dTEM ) measured from TEM images with Image Pro Plus program are also listed in Table 2.
Although Lindner et. al. [1] suggested the laser treated layer on similar samples to be nanocristalline, we could not find evidence for that, in fact every sample had an ultra fine grained structure with grain sizes well above 100 nm.

After the fatigue tests, broken specimens were investigated in SEM with the aim of determining location and number of initiation places and investigating the micromechanism of fatigue crack initiation and evolution in DMLS Ti6Al4V.
The microstructure in the first case is composed of thin α′-martensite needles (Fig. 2) distributed within packets (Fig. 5a), which show the prior beta phase grain boundaries (white arrows).
Frontal plane orientation map showing that the prior β columnar grain is composed of several α′ needles variants that repeat during successive depositions.
The stress relieved components still features elongated prior β grain boundaries but they are larger compared to Ti64-HT1 treatment (Fig. 5a).
Observed differences consist in number of initiation places according to the longitudinal specimen direction with respect to the build direction.

Each small area represents the instantaneous location of an abrasive grain as it passes through the contact zone.
The time that grain in contact zone is equal to csl v , nearly 100 microseconds.
A single grain interaction moves past a point on the workpiece at wheel speed so that a typical heat pulse is experienced for about 1 microsecond [3].
Peclet Number is a dimensionless parameter proportional to the sliding speed vw and contact length of the sliding heat source and inversely proportional to the thermal diffusivity of the material under the heat source. γ is the thermal diffusivity defined as k cγ ρ= .
In the short instant, the heat generates by grains friction and cutting in the grinding contact zone between wheel and workpiece can be realized as steady-state heat source.

After 24 h incubating, MTS assay was used to detremine the live cell number.
The grow factor of the cells on the Mg alloys was defined as the ratio of the live cell number in extraction media to that of the control.
The grain size decreased with the increase of Ca content from 0.5 to 15.0, whilst the Mg2Ca phase distributed along Mg(α) primary grain boundaries increased (Fig. 1 (a-f)).
Mg-20Ca showed large grain size and a large amount of Mg2Ca phase (Fig. 1 (g)).
It can also be seen that yttrium addition reduced the boundaries between Mg2Ca phase and Mg (α) primary grains (Fig. 1 (b) and (h)).

GPS / Well ID n Ns ρs /105cm-2 Ni ρi /105cm-2 P(X2) /% T±δ/Ma Xingdi ZFT-1 Z2 N:41°13′38″ E:87°56′12″ 21 5011 213.291 2026 86.236 5.9 431±24 Queer- queke ZFT-2 ∈3t N:40°53′43″ E:88°18′24″ 17 4081 206.546 1778 89.987 0 410±19 ZFT-3 O2q 22 5885 166.763 2614 74.073 0.02 396±15 Yang- baoshan ZFT-4 O2q N:40°44′38″ E:88°32′25″ 5 1098 253.861 469 108.434 78.0 421±14 Yaerdang ZFT-6 Z2 N:40°44′41″ E:88°59′31″ 17 4052 174.664 1496 64.486 0 490±39 Xiang- yangcun ZFT-7 S1t N:40°47′32″ E:89°25′5″ 23 6191 186.333 3099 93.272 0.33 345±11 ZFT-9 S1t KQ1 25 6421 161.285 3000 75.355 0.02 399±17 n=grain number, ρs=induced track density.
Number of tracks counted or measured is shown in parentheses.
P(X2)=chi-square probability, which is a measure of probability that individual grains counted in a sample are from a single population; ages were determined using average age when values of P(X2) <5%, which are generally taken to indicate that multiple are population are present.
Fig.1 The estimation age population in a mixed distribution of ZFT grain ages, using the binomial peak-fitting method (Brandon, 2002) Fig. 2 The time-temperature history of sample AFT-2, AFT-6 and AFT-4 in Kuruketage area The AFT ages of the sample from Kuruketage area and core samples form Konguehe slope range form (164±11)Ma to (73±7)Ma (Table 2)and were much younger than the depositional ages.
The test probability P(X2) of single grain ages of the most samples (except AFT-3) are lower than 5%, which indicate that the AFT ages of the most samples have the single province (Kerry et al., 1998).