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The mechanical alloying process has a number of advantages including grain refinement, homogeneous distribution of reinforcement, extended solid solubility, and the formation of metastable or amorphous phases, depending on the initial powder composition and processing condition.
Generally, the strength of Al alloys rapidly decreases at temperatures above 300 o C, because of the growth of precipitates and grains.
It was clear that the size of the Al grains significantly decreased to submicron range.

In order to establish a mathematical model for laser dressing of such a wheel, the following assumptions are made: (1) The bronze-bonded diamond grinding wheel is densely bonded wheel without porosities. (2) Abrasive grains used in wheel are small balls. (3) The grinding wheel has dense and uniform distribution of abrasive grains.
Similar to the representation for Eq.1, i and j are adopted for numbering the nodal points on x and y axes, and m and n for the maximum values of i and j, respectively.
The holding ability of the abrasive grains by the bond material is not compromised by the laser ablation.

However, the average four point bending strength does not show a linear trend with increasing TiN content and this is due to a number of factors related to the ceramic processing.
SEM showed the larger TiN grains homogenously dispersed in the Si3N4+TiN layers (Fig. 3).
Discussion The homogenous addition of TiN into the hot-pressed Si3N4 leads to a microstructure where the larger TiN grains are evenly dispersed.
The scatter of the four point bend strength data is related to processing problems associated with the agglomeration of TiN grains [6].

The Hf content was selected so as to minimize a size of oxide particles and thus to increase their number density on the basis of our previous study [7].
Another one is that grain boundary sliding could accelerate the deformation and decrease the strength far below the threshold stress, since grain size of Co-base ODS alloys is fine as several μm.
A removal of Al2O3 inclusions and the coarsening of grain size could be effective way to further improve the high-temperature strength of Co-base ODS Fig. 7 HRTEM micrograph of Y2Hf2O7 alloys.

Introduction Glass-ceramics is composed of specific based glass, in heating process through the control made the crystallization of a class of contains a large number of microcrystalline phase and glass phase of polycrystalline solid materials[1,2].
Sintering temperature is too high, grain coarsening affect the strength of the coating.
To avoid long time caused sintering grain coarsening phenomenon, the process of experiment is improving the sintering temperature and reducing sintering time to 10 min.
According to the principle of dispersion strengthening and Fine-grain strengthening, the theory of Particle dispersion toughening and The crack toughening [7], the coating can increase the strength and fracture toughness of the glass-ceramics coating by adding ZrO2 .

Table 2 Influences of the ratio of NH4H2PO4 to MgO on the fluidity and strength P :M Mix ratio Borax（%） Slump（mm） Slump flow（mm） Compressive Strength（MPa） C:G:S:W 2h 1d 7d 28d 1 :2 1:1:0.53:0.217 1 265 510 22.6 40.5 50.1 54.5 1 :3 1:1:0.53:0.217 1 105 320 20.1 27.2 30..5 33.2 1 :4 1:1:0.53:0.217 1 20 205 18.5 25.6 28.2 28.5 The above results show that, the slump and slump flow of phosphate concrete prepared by P/M ratio of 1:2 was a large number of degrees than the P/M ratio of 1:3 and P/M ratio of 1:4 phosphate cement.
Influences of grain composition of gravel on the fluidity and strength of phosphate concrete The experiment investigated the mobility and strength of phosphate concrete which prepared with three kinds of gravels as shown in Table 5, such as 5~10mm, 5~20mm, and 5~25mm.
Table 5 The grain composition of gravel Sieve pore (mm) Gravel 1# Gravel 2# Gravel 3# Separation sieve (%) Cumulative sieve (%) Separation sieve (%) Cumulative sieve (%) Separation sieve (%) Cumulative sieve (%) 31.5 0 0 0 0 0 0 26.5 0 0 0 0 0.7 1 16.0 0 0 0 0 43.5 45 9.50 6.2 6 45.4 45 — — 4.75 81.2 87 50.4 96 55.1 100 2.36 10.9 98 3.3 99 0 100 Sieve bottom 1.7 100 0.9 100 0.7 101 Table 6 Influences of grain composition of gravel on the fluidity and strength of phosphate concrete Gravel Mix ratio Borax （%） Slump （mm） Slump flow （mm） Compressive Strength （MPa） C:G:S:W 2h 1d 7d 28d 1# 1:1:0.53:0.217 1 240 490 21.5 40.0 47.5 50.8 2# 1:1:0.53:0.217 1 265 510 22.6 40.5 50.1 54.5 3# 1:1:0.53:0.217 1 270 460 20.5 40.2 49.0 53.7 As the results been shown from Table 6 that the mobility of the phosphate concrete which prepared by the three kinds of gravels such as 5~10mm, 5~20mm, and 5~25mm were almost the same.

The peaks pointed in the diffractogram of Fig. 1 and in the Fig. 3, correspond to the diffraction pattern data sheets number 00-029-0359 (α-TCP), 00-009-0432 (Hydroxyapatite) and 00-046-0905 (Calcium Deficient Hydroxyapatite – CDHA) of the Joint Committee on Powder Standards Diffraction - JCPDS.
In micrographs of the M05T13 and M05T15 samples, can be observed hydroxyapatite needles formation and grains of Hadley [14].
At the end of the reaction, when nearly all α-TCP was consumed, there will be a shell of hydroxyapatite (CDHA) with an empty inside (Hadley grains), where the particle originally α-TCP was completely solubilized [14].
The M05T13 and M05T15 samples showed the formation of hydroxyapatite needles and grains of Hadley in its structure.

The grain size and lattice parameter of the Pt/MC estimated by the Scherrer's equation based on the crystal face of (111) were 3.48, 3.18 and 3.01 nm, respectively, for MC prepared at 850, 900 and 950 oC.
Tca [°C] Pt loading [wt%] EAs [m2 g-1] grain sizeb [nm] c. d.c [mA cm-2] MAc [A g-1] SAc [μA cm-2] lPt(110)/ EAs IPt(111) / IPt(220)b 850 10.42 75.53 3.476 0.739 12.36 16.36 0.0496 4.72 900 13.49 85.61 3.174 1.196 15.45 18.05 0.0631 5.15 950 11.53 92.53 3.011 0.884 13.36 14.44 0.0572 4.75 aThe carbonization temperature for preparing MC (P/Si=0.5), banalyzed by XRD, cdata obtained at overpotential of 0.1 V.
The maximum MA and SA of ORR on Pt/MC (P/Si = 0.5) with Tc = 900 °C were experimentally found to be 15.54 A g-1 and 18.05 mA cm-2, respectively, due to the smaller Pt grain size (3.174 nm) and higher lPt(110)/EA and IPt(111)/IPt(200) ratios.
Acknowledgements This work was financially supported by the National Science Council Republic of China (Project number: NSC 99-2120-M-011-001).

The fatigue life was defined as the number of cycles in which the load was reduced by 20%.
It has been reported that a miniature size specimen consists of a few grains or a single grain so that the mechanical properties of the specimen are strongly depended on the crystal orientation of the grain [7].

., grain refinement and precipitation strengthening, lose their effectiveness as temperature increases.
The KAM map shows that the boundaries of the wedge-shaped deformation bands exhibit a higher KAM value, and that the KAM value gradually decreases as the distance from the Si phase increases, i.e., the value was higher near the Si phase and lower inside the grain.
Since high KAM values reflect higher dislocation densities [16], this implies that the dislocation density at the interface between the wedge-shaped deformation band and the Al matrix is higher near the Si phase and decreases gradually as close to the inside of Al grain.
Acknowledgements This work was supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI (grant numbers 21K18826).