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Sinter + HIP is effective when the grain size is very fine and the cobalt content is low while sinter/HIP technique is effective in the case of moderate grain size and cobalt levels.
Grade Carbide content, wt% Mean grain size of carbides, mm Binder composition Microstructure of binder Hardness, HV** [MPa] Transverse rupture strength, RTZ**, [GPa] C13 WC, 87 1.8 Co (W) Co 1300 ... 1320 2.7 ... 3.1 T70/14 TiC, 70 2.1 Fe (14Ni) austenite * 1250 ... 1280 2.1 ... 2.3 T75/14 TiC, 75 2.0 Fe (14Ni) austenite* 1360 ... 1390 1.8 ... 2.0 T75/14-H*** TiC, 75 2.0 Fe(14Ni) austenite* 1360 ... 1390 2.3 ... 2.5 * traces of martensite; ** characteristics of different batches; *** produced using Sinter/HIP Fig. 1 The scheme of adhesive wear testing: 1 – mild steel to be turned; 2 – cermet specimen; h – height of wear land of the specimen; L1 −adhesive wear resistance; L- cutting path Fig. 2.
Confidence interval of the wear resistance did not exceed 10% while the number of test pieces was three as a minimum.

Typical graphene flakes are in the range of 5-100 µm2, thus these defects cannot be considered as the seeds for carbon grains.
For misoriented samples C-face sublimation of Si is more effective due to a significant number of terrace edges and higher active surface area.
C-face SiC enables the growth of as many as 100 carbon layers but the growth rate is non-linear, which indicates that Si diffusion through graphene grains boundaries is a limiting factor.
The growth rate, higher for misoriented substrates, decreases with graphitization time because of slower Si diffusion through graphene grains.

The research shows that the high strength and high ductility of multi-phase alloy steel have related with the heat treatment technique, the addition of strong carbide forming elements and the formation of fine ferrite grain.
(a) at 650oC (b) at 680oC (c) at 710oC (d) at 740oC Figure4 Microstructure photograph of heat treatment program B The mechanical performance characteristics of FMA multiphase alloy steel As the multi-phase microstructure of the steel with all kinds of strengthening means of grain refinement, grain boundary strengthening, the second-phase dispersion strengthening, and toughening of retained austenite, etc., so FMA multiphase alloy has very good overall performance, four aspects are listed in the following: (1) High strength, high toughness and high work-hardening rate.
Table 3 Test result of mechanical properties Serial number σ b (MPa) σ0.2 (MPa) ψ (%) δ (%) A-1 A-1 641 641 466 466 70 70 27 27 A-2 A-2 638 638 463 463 71 71 28 28 A-3 A-3 653 653 470 470 69 69 26 26 A-4 A-4 643 643 466 466 70 70 25 25 B-2 B-2 650 650 435 435 71 71 33 33 B-3 B-3 645 645 355 355 70 70 31 31 (2) FMA multi-phase alloy steel with the continuous stress-strain curve under the tension, that is, the stress-strain curve of FMA multi-phase alloy steel have no yield platform (as shown in Figure 5), this indicate its work-hardening rate are higher than ordinary low carbon steel and low alloy steel.

The corrosion spots first appeared above the entrance to the room, then around the cooling units and gradually increased in number and size.
No local attack at grain boundaries was confirmed, even below the corrosion pits, Figs. 4, 5.
The heat affected area of the weldment could not be recognized well, but there was an area of coarsened austenitic grains on the inner surface of the tube adjacent to the fusion zone, see Fig. 13.
Coarse austenitic grains at the weld root However, the original cause of the damage was revealed on a cross-section through a visually undamaged portion of this weld.

In order to obtain complete solid solution Mg2Si0.8Ge0.2, the powders(x=0.2) gained at the first step solid state reaction were molded again by dry-pressing and heated up to 1073K, held for 10 hours, to homogenize the components and proceed the grain growth.
It's very clear that the powders are composed of agglomerates (granularity ≈ 5µm) of very small size crystal grains.
The grain size arranges compactly, and nearly there is no pore existing .The density of samples measured by Aruchimedes'principle and the calculation of the volume and measure weight was almost 99.9% of theoretical value.
(1) Where m+* is carrier (hole) effective mass, h is Plank number, p is carrier concentration is index (200) (311) (400) (422) (511) Mg2Si0.8Ge0.2 3.1862 1.9201 1.5908 1.2989 1.2245 Mg2Si0.8Ge0.2+12000ppmAg 3.1884 1.9217 1.5918 1.2992 1.2250 Table 1 d-values changes for crystal planes of Mg2Si0.8Ge0.2 with 12000 ppmAg doped Fig.5 Temperature dependence of electrical conductivity for Ag-doped Mg2Si0.8Ge0.2 scattering factor.

Now a number of workers have investigated on the properties of powders and sintering parameters to improve mechanical properties of zirconia ceramic[5~16].
a b c Fig. 2 SEM of MgO-PSZ green parts injected at different pressure (MPa) (a) 20, (b) 30, (c) 50 Microstructure of MgO-PSZ tube The thermal shock resistance of ZrO2-based electrolytes is related to the composition, fabrication process, impurities, grain sizes, phase distribution, etc[17].
From Fig. 3 (b), which is the fracture face of the tube, it can be concluded that the grain size was about 4 mm.
On the other hand, the volume shrinkage around 1131 °C is corresponding to the phase transformation from monoclinic to tetragonal for large crystalline grains.

It is owing to that, during heating process of recrystallization annealing, tin phase, with an eutectic point about 228.3℃, melts, and then accompanying equiaxial transform of α-A phase grains, it graually congregates in much larger gaps where three grains of α-A phase bord Fig. 3 The SEM morphologies of bimetal bonding interface (a) Cold rolling state; (b) recrystallization state; (c) fractionated gain of fig.3b (a) (b) (c) Compared with Fig. 3a and Fig. 3b, it can be found that, as for high-tin aluminum alloy, when it has been cold-rolled, the structure of which becomes comparatively fine and dense, shrinkage cavities and pores nearly disappear, however, influenced by heating process of recrystallization annealing, pores and shrinkage cavities obviously appears again.
However, due to the heating effect of recrystallization annealing, gas-phase atoms present activate status, and again precipitate from alloy matrix in the subsequent slow-cooling stages, then cluster towards grain boundary so as to form new pores, the wall of which is far rougher than that of casting pores.
Secondly, the bonding interface, between Al alloy strip and steel back, is irregular, existing large numbers of peaks and valleys, and embedding or occluding each other, as shown in Fig.3c.  

The affinity of W and C atoms, easy to combine into a high melting point, high hardness of W2C, W2C exhalation in the subsequent cooling process, can effectively prevent grain growing up.
By figure you can see, the weld bead of tiny grains, the rules of the polygon, the casting of silicon carbide acicular, carbide and some trees, and the shape, the needle, branches form carbides should be liquid in the product of precipitation, both the WC first decomposition, oxidation, recrystallization, and then in the process of cooling from the liquid precipitation of W2C, because of weld cooling speed faster, carbide showed acicular or branches, small particles is not completely dissolved the WC particles [5].
With the increase of the content of Mo, V elements corresponding increase in the number of quality, so as to improve the hardness and wear resistance of the surfacing layer.
And excess elements segregation in the grain boundary, Mo, V in surfacing layer cracking, Mo, V element content in the alloy powder cannot be too high.

On the other hand, the solid phase processing techniques have some advantages such as the uniform distribution and no clustering of the reinforcements, fine grained structures and easy controlling of the composite microstructure[2-4].
With the increase of the SiC mean grain size and the ratio of the reinforcements to the matrix, the SiC particles distribution is more and more uniform in the composites.
With the increase of the SiC particle size and volume fraction increases, the number of the SiC grain fractures increase.

Lath edges and prior austenite grain boundaries, on the other hand, appear relatively free of cementite.
Here we observe considerable amounts of retained austenite between martensite laths and in the prior austenite grain boundaries, as well as isolated regions containing few carbides.
As the partitioning temperature is increased, so does the amount of coarser grain boundary retained austenite (Figs. 2(c) and 2(d)).
Acknowledgements The authors would like to a number of people for their assistance in performing this research.