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At the same time, the grains of weld metal and heat affected zone are refined.
The difference of the structure between the HAZ and the base metal is decreased, the matrix structure is lamellar pearlite, ferrite distributes uniformly along the grain boundary.
And the dimension of grains becomes finer, more homogeneous and rounder with the filling speed of Ni wire increasing.
In Fig. 4, WE1, WE2 and WE3 represent the number of samples.
Test type Number of joint [pcs] bending angle [°] Number of generating the crack [pcs] Type Ⅰ 20 180 20 Type Ⅱ 20 180 18 Type Ⅲ 20 180 18 Type Ⅳ 20 180 2 Fig. 4 Crack length of root bending test.

Experimental study on Laser Metal Deposition of FGMs with Ultrasonic Vibration Lanyun Qin1,2,a Wei Wang1,2,b Guang Yang2,c 1 Shenyang University of Technology, Shenyang,110016,China 2 Shenyang Aerospace University, Shenyang, 110134, China aqinly@sau.edu.cn, bwangw1116@ sau.edu.cn, cyangguang@sau.edu.cn Keywords: Ultrasonic vibration; Laser Metal Deposition; Laser; FGM; Titanium alloy Abstract: Referring to the ultrasonic vibration effect on casting, welding and laser cladding, the paper demonstrates the feasibility that it can be also used in Laser Metal Deposition(LMD)of titanium alloy to protect the defects such as crack,pore and oxidation and refine the grain size and improve the distribution uniformity of solidified structure.So the paper applies ultrasonic vibration system to fabricate the functionally graded materials(FGMs) samples and analyses its effect on the specimen microstructure and mechanical property by experiments.The results show that ultrasonic vibration can suppress
the formation of pore, refine the grain and make the TiC hard phase more homogeneous in the FGMs parts, which is also indicated by the microhardness tests.
(a) (b) a-Pore morphology of cladding layer without ultrasonic vibration a- Pore morphology of cladding layer with ultrasonic vibration Fig. 2 Effect of ultrasonic vibration on pores of cladding layer (100%TC4) As shown in Fig.2, the number and size of pores in cladding layer with ultrasonic vibration is less and smaller significantly.
Under the ultrasonic vibration the TiC grain size is 1.5μm, which is smaller than that without, which shows that ultrasonic vibration can refine the grain and make the reinforcement phase distribution uniform.
(1) Ultrasonic vibration will help to suppress the formation of pore and reduce its size； (2) By analysing the microstructure of middle cladding layers, it can be found that the grain size is refined for ultrasonic vibration breaking the longer dendrite;Furthermore,in the FGMs specimens, reinforced phase TiC particle size is smaller and get more uniformity distribution; (3) The microhardness tests indicate that gradient materials specimens have good hardness consistency and high mechanical property, which show the ultrasonic vibration can refine the cladding layers and homogenize the microstructure，and then improve its mechanical property.

One is the grain size effect, and the other is the feature/specimen size effect.
This effect shows that a material with smaller grain size demonstrates higher strength than one with larger grain size.
The other is the feature/specimen size effect and its interaction with the grain size effect.
With the trend toward increasing miniaturization, the number of grains across the cross section (N) decreases.
For example, in this figure, the tool stroke at step number 1 is 0.12 mm and it increases 5 μm at every step.

It contains uniformly distributed silicon particles in the Al matrix of fine equiaxed grains.
The number of Si particles size greater than 5 μm acounted for 15% in extruded alloy, compared with 5%  after solution at 500˚C for 30 min.
The averaged grain size of the Al matrix on the longitudinal section of the extruded alloy is 6.1 μm.
Deformed Al-12.7Si-0.7Mg alloy consists of fine euqiaxed grains of Al matrix with uniformly distributed fine Si on the grain boundaries.
The averaged grain size of the Al matrix on the longitudinal section of the extruded alloy is 6.1 μm.

Crack growth may finally lead to component failure after a critical number of cycles.
In Fig. 3 (b), the morphology of carbides within the grain interior of alloy B and alloy C reveals script-like carbides precipitated.
Fig.3(c) presents sheet-like carbides precipitated at the grain boundaries.
Fig.3 SEM-BSE images present the carbide morphology (a) blocky carbides within grain interior in alloy A, (b) script-like carbides and (c) sheet-like carbides at grain boundaries in alloy C.
There are a larger amount of script-like carbides in alloy C than the other alloys, which distribute in grain boundaries (Fig.2c).

Based on the micro mathematical model, the average grain size and the average grain radius for Al-4.5%Cu twin-roll continuous casting thin strip is investigated and analyzed.
Each CA unit was given one random number r(0≤r≤1) in every time-step δt.
Fig.3 The average grain size, the average grain radius of thin strip and the average columnar crystals deviation of Twin-roll casting Al-4.5%Cu strip It is found from Fig.2 and Fig.3 that the predicted results are relatively consistent to the measured ones, indicating that the mathematicmodel is reliable thus can be used to predict the effects of processing parameters on the solidification structure of twin-roll thin strips.
(2) The average grain radius and the average columnar crystals deviation were measured.
The performance of Al–Ti–C grain refiners in twin-roll casting of aluminum foilstock[J].

Results showed necking of the nano-silver powder, which indicated the occurrence of sintering through grain boundary diffusion process.
Fig. 5, 500x Magnification of sintered 250 µm silver powder at 250°C Fig. 6, 1000x Magnification of sintered 250 µm silver powder at 250°C Fig. 7, 5000x Magnification of 250 µm silver powder at 250°C As highlighted [8] attributed this processes to the minimization of enthalpy in the form of Gibb’s free energy, which is related to the number of bonds.
Excess Gibbs free energy drives the agglomerate to become more compact (close packed structure), which results in an increase in the number of bonds.
In summary, the sintering process of Ag agglomerates goes through various sub processes such rearrangement of particles with sintering, growth of necks with neighbouring particles, coalescence of particles through grain boundary diffusion process, as shown in Fig.8.
In this study, the Ag agglomerates experience a number of changes to its morphology: (i) partial sintering was observed for the control sample at 1000C, predominantly due to rearrangement of weakly bonded particles; (ii) At 2500C, the agglomerates shows a more drastic changes in the particle morphology associated with the formation of necking and beginning of coalescence between particles.

A suppression of the recrystallization is particularly important for the single crystals of Ni base superalloys, since an appearance of the new grains means a destruction of the single crystal structure.
The recrystallization in a course of the HIP is an undesirable phenomenon in the polycrystals too because the boundaries of the new grains can be weakened as compared with the boundaries of “the old” grains.
The size and number of the pores in the blades before and after the HIP.
The size and number of the pores in the operated blades before*) and after the HIP.
Table 3 shows that the maximum pore size is decreased by 4-6 times, the total number of the pores is reduced in 2-7 times by HIP.

Based on a number of stratigraphic sedimentary information included in log data, application of the Artificial Neural Network to identify sedimentary microfacies from well logging data can complete the series auto-interpreting.
Compared with the braided delta and delta, delta sediment grain size is smaller, and the rock is sandstone, fine sandstone and mudstone [8].
Underwater distributary channel is fining upward grain size, natural gamma curve is typical funnel-shaped, and the neutron and density logging curves also show no typical funnel-shaped.
Table 1 Logging curve parameters and geological significance Logging curve parameters Geological significance Magnitude Logging curve Deposition rate and water energy Symmetry Sediment grain size and sedimentary rhythm Peak position Sedimentary rhythm and hydrodynamic nature Peak number Sediment homogeneity and sedimentary water energy Center of gravity Hydrodynamic and sedimentary cycle changes Volatility Sedimentary energy change Water fluctuation Hydrodynamic properties and water depth change 3.
Table 2 Neural network containing gas in the Ordos Basin sedimentary facies identification results Well Number of samples Recognition results entirely correct number of samples Recognition results partially correct number of samples Recognition results wrong number of samples SU12 103 82(79.8%) 15(15.4%) 6(5.8%) SAN111 79 69(87.2%) 5(6.4%) 5(6.4%) YU20 54 44(81.5%) 7(12.9%) 3(5.6%) Total 236 195(82.7%) 27(11.4%) 14(5.9%) Conclusions 1) The usual pattern recognition method is based identification method to identify rules.

Due to the need for structural integrity and cost minimisation, the aerospace industry is designing highly unitised components that combine a large number of features on one product.
A 1 µm grain size is very fine and gives a uniform distribution of cobalt through the diamond matrix.
This area was examined in several samples which had been treated in this way and which had different PCD grain sizes.
Due to the large number of variables and the range of their corresponding levels, it is impractical to apply full factorial Design of Experiment (DOE) in practice [25].
Some of the constraints such as grain size, pre-processing of raw material and dielectric condition are difficult to control.