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Results Results of strength degradation as a function of numbers of fatigue cycles for the glass-infiltrated alumina and spinel are shown in Fig. 1.
All specimens show an abrupt transition in strength with increasing number of cycles at various contact loads. 10-1 100 101 102 103 104 105 10 6 107 108 0 100 200 300 400 500 600 200 N 500 N 1000 N Strength (MPa) Number of cycles 10 1 10 2 10 3 10 4 10 5 10 6 0 100 200 300 400 1000 N 500 N 200 N Strength (MPa) Number of cycles (a) (b) Fig. 1.
Abnormal grain growth caused by recrystallization may be attributed to low strength.
The interface sliding may initiate microcracks and then form macroscopic radial cracks after large number of cyclic contacts, resulting in drastic reduction in lifetime and strength.
As loads and numbers of contact cycles rose, the damage mode was changed from brittle fracture (ring crack) to deformation (radial crack) mode.

With a main emphasis on advanced materials and engineering studies, the instrument will enable 2D/3D mapping of the microstructure, chemical composition, and crystallographic structure (grain size, stress and strain, phase position, texture, and so on).
Compared with grain size and preferred orientation, strain mapping might need better energy resolution around 0.2-0.4%.
Imaging techniques and scientific cases for this instrument have been discussed with potential users at a number of workshops and conferences.

The nano-sized diamond slurry (average grain size of 25nm) added in KOH-based colloidal silica slurry resulted in a material removal rate (MRR) of 0.07mg/hr and the Ra of 1.811Å.
While many deep scratches were exhibited on the surface of SiC substrate obtained through the CMP process using KOH-based colloidal silica slurry, the addition of diamond slurry reduced the scratches on SiC surface but small number of scratches was still remained.
The nano-sized diamond slurry (grain size of 25nm) added in KOH-based colloidal silica slurry resulted in a material removal rate (MRR) of 0.06mg/hr and the Ra of 1.811Å.

Furthermore, it produces finer grain size than conventional sintering methods.
The development of this kind of materials not only brings great advantages, but also creates a number of problems, such as poor mechanical properties or the need for stric manufacturing parameter control.
The M6C and MC carbide can be easily distinguished, and M6C carbide is evenly distributed in the grain.

The complex phenomenon of contamination is described in this paper in order to demonstrate its importance, as the number of failures of steel components is growing every year.
Corrosion characteristics of crudes are defined by total sulphur (S) content, total acid number, salt and water content, and microorganisms.
Fuels may be classified as slightly or highly contaminated by the number of microorganisms present in the water bottoms: 105 bacteria/ml and 103–104 fungi/ml for slight contamination and 106–108 bacteria/ml and 104–106 fungi/ml for high contamination.
EDAX analysis in line at the grain boundaries At the transition zone of different kinds of fracture it can be seen that the S content increased a lot, indicating the start of the contaminated zone of the steel (Fig. 4).

Abstract: Reducing oxide inclusions’ number and size by aluminum deoxidization is an effective way for improving working life of high strength steel.
For this purpose, during inert gas protection electro–slag remelting (P–ESR) process and H13 steel as electrodes, the deoxidizer being made of aluminum grains, iron powder and calcium fluoride powder mixture was added into slag pool with different addition rates.
Based on observation by SEM, it was obviously that number and size of inclusion particles in Ingot–1 was less and smaller than that in electrode, respectively.
That meant residence time of inclusions got longer in molten steel during P–ESR process and not only number of inclusions left in steel increased.
Based on results, P–ESR reduced number and size of inclusion particles in steel, and adding aluminum not only improved and alerted composition of inclusion.

Generally, a fine grained microstructure is desirable for improved mechanical strength and wear of glass-ceramics [6-8].
This mean lower SiO2/P2O5 ratio eased fast nucleation with larger number of nuclei before the crystal growth process and needles seemed finely dispersed with high aspect ratio and diameter was in nano-sized regime.
Glasses containing higher SiO2/P2O5 ratio resulted in slow crystal nucleation with small number of nuclei at initial stage and crystal size appeared larger than ones with lower SiO2/P2O5 ratio.
Samarawickrama, The nucleation and crystallization of fine grained leucite glass-ceramics for dental applications, Dent.

After the heat treatment, the number of cracks increased resulting in a multi-cracked coating with fine cracks dispersed all throughout the coating.
Fig 4 (d) shows the presence at the duplex scale/coating interface of nanometric grains found to be rich in Al and RE, which could reveal the formation of a (RE)AlO3 perovskite phase by a reaction in the solid state between Al2O3 and RExOy, favoured by an Al supply coming from the substrate.
Such phases have been proposed to play a role in the increase of adherence of protective oxide scales on chromia- or alumina-forming alloys [8, 9] by segregating at the oxide grain boundaries and at the alloy/oxide scale interface.
Hf-rich pegs Hf-rich pegs (a) (b) Hf-rich pegs nanograins band (c) (d) Figure 4: Evolution of the coating/oxide scales system with number of cycles at 1100°C in air (a) 550 cycles; (b) 1020 cycles; (c) 1550 cycles and (d) nanograined structure between the RExOy coating and the oxide scale.

When the isothermal temperature is low, the bainitic ferrite grain becomes small, the number of carbide increases and the shape changes from discontinuous rod-shaped or lamellar into flakes.
The number of the lower bainite increases with the isothermal temperature increases.
When the quenching temperature is 320°C, the grain becomes large with a certain amount of residual austenite and massive bainite, as shown in Fig. 3c.

Fig.3 shows that the number of pores decreased and enhanced the formation of granular-shaped grains, with increasing crystallization temperature (1500°C), indicating. that the crystallization temperature is a critical factor influencing the microstructure of glass ceramics. 3.4 Mechanical properties Table 3.
Upon increasing the crystallization temperature, the number of pores decreased and enhanced the formation of granular grains.