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The additional layer (dark etching layer) observed between the compound layer and diffusion zone appears to be columnar grains of γ' (Fe4N) + α-Fe.
Precipitates along prior austenite grain boundaries near the surface were all coarser than the precipitates observed at the core of the treated samples.
The number of cracks was particularly high for the samples treated at 550 and 580 0C (Fig. 3(c) and 3(d)).

For the assessment, the sum of the openings along the glue line and at the end grain developed during the tests has to be taken in relation to the total glue line length at the end grain of the specimen.
Table 1: Test program for delamination and shear tests Series Test method Standard Shape Sizes [mm] Number Material Adhesive 01 Delamination EN 391-A Block b/h/l = 160/320/75 51 GL28k-spruce PUR 02 Delamination EN 391-A Block b/h/l = 160/160/75 42 GL24k-spruce MUF 03 Delamination EN 391-A Core Ø 35, l = 80 17 GL28k-spruce PUR 04 Delamination EN 391-A Core Ø 35, l = 80 14 GL24k-spruce MUF 05 Shear test EN 392 Core Ø 35, l = 80 51 GL28k-spruce PUR 06 Shear test EN 392 Core Ø 35, l = 80 42 GL24k-spruce MUF 07 Shear test EN 392 Core Ø 35, l = 80 9 GL24h-spruce RF 08 Shear test EN 408 Block b/h/l = 32/55/300 9 GL24h-spruce RF 09 Shear test - Block b/h/l = 160/200/200 17 GL28k-spruce PUR 10 Shear test - Block b/h/l = 160/200/200 14 GL24k-spruce MUF 11 Shear test - Beam b/h/l = 160/320/1350 17 GL28k-spruce PUR 12 Shear test - Beam b/h/l = 160/160/800 14 GL24k-spruce MUF 13 Shear test - Beam b/h/l = 80/120/650 9 GL24h-spruce RF Experimental results Delamination tests according to EN 391

In process of ultra-high speed grinding, keeping the other parameters unchanged, the chip thickness of every grinding particle will become thinning out with the grinding speed’s great improving, active grains’ increasing in unit-time and the thickness of the wear debris ‘being smalling cutted by abrasive grit.
High speed grinding has the following outstanding technical advantages compared with ordinary grinding [19]: High speed grinding can greatly improve the grinding efficiency and reduce the equipment number.
In the same material removal rate .High-speed grinding can reduce the cutting depth of single grains, thereby reducing the grinding force and getting the high quality of the workpiece surface .Especially in machining the lower stiffness (such as thin-walled parts )of the workpiece.

Basically, these methods describe surface grinding and cylindrical grinding processes using two-dimensional model grains, by calculating the roughness, or the topological cross section, of a workpiece and the chip thickness [11-13].
Base on a large number of grinding experimental data, Liang Shi set up the computer simulation model of cylindrical plunge grinding and realized the simulation analysis and prediction [38].
Vol. 11 (2011), p. 169 (In Chinese) [33] Yanlan: Research on Grinding Mechanism of Hardened Cold-work Die Steel Based on Single Grain Cutting (Doctor Degree, Hunan University, China 2010), p. 15 (In Chinese) [34] S.

In the final rupture region, the fracture surface mainly appears as a typical semi-brittle fracture mode, and some dimples, plastic micro-voids, and plastic deformations at grain boundary as well, can be observed on the fatigue fracture surface, as shown in Fig. 6(e) and Fig. 6(f).
Furthermore, the size and number of dimples decrease with increasing applied stress range, which suggests that the fracture mode in the final rupture region transforms from ductile fracture mode to semi-brittle fracture mode.
Low cycle fatigue behaviors and microstructures of Ti-2Al-2.5Zr with fine grain at RT and 77K.

The powder metallurgy(PM) superalloy has shown highly homogeneous structure containing fine grains, annealing twins and prior particle boundaries (PPBs) as well as brittle MC carbides [9].
Maybe more important, it is evident from Fig. 4(b) that the MC contains a number of stable oxides ZrO2 with an average diameter of 20nm as the nuclei accelerate the preferential precipitation of carbides which forms the continuous harmful PPBs.
Effect of oxygen content on impact toughness of a fine-grained magnesium alloy, Materials Letters. 65 (2011) 2995-3001

Fig. 1 Particles size distribution of Al2O3 powder The morphology of the grains of Al2O3 at 250 °C and 900 °C, was observed by scanning electron microscopy (Fig. 2).
This indicates that the oxidation heat treatment does not affect the grain morphology.
Fig. 3 Adsorption isotherms of water vapor onto Al2O3 samples at 25 °C Depending on whether 10.6 Å2 or 14.8 Å2 area can be taken by a water molecule [19], from the amount of adsorbed water vapor and the cross sectional-area of the polar head, it is possible to calculate approximately the hydrophilic and hydrophobic parts of the alumina samples surface according to the following equation: S=Na×Γads×σ (1) Where: Na is the Avogadro’s number; Γads: the amount of adsorbed vapor water (µmol.g-1); s : area of gas molecule (Å2), with: s H2O = 10,6 Å2 or 14,8Å2 and s C4H10 = 44.6 Å2 The values of hydrophilic and hydrophobic surface areas obtained are listed in Table 2 and 3, successfully.

Of special interest among the by-products of grain-crops in Russia is rice husk (RH).
While processing rice grain into rice grits, rice husk as the by-product amounts up to 20%, i.e. tens of thousands of tons annually, taking into account that rice is one of the major food products in the world and ranks number 2 in the world after wheat in crops [4].

Table 2: Strength characteristics of reinforced interlining and their unmodified analogues Interlining type Breaking load*, N/cm Elongation at rupture*, % Length wise Grain cross Length wise Grain cross FI art.
Table 4: The characterization of reinforced interlining line “PArMa” Groups of garments Number of articles “PArMa” Modification according to the type of a used textile liner web Interlining qualities Flexural rigidity (EI), 10 -3 N×cm2 ∆ EI, 10 -3 N×cm2 Elasticity, % Coat-suit 20 – 25 KN, KM, KS, NWM, NWS* 2,75 – 16,4 0,68 75 – 95 Corsetry cloth 15 – 20 KN, KM, NWM 16,41 – 41,2 1,3 80 – 100 Technological (furniture, notions, shoes) 18 – 22 KM, KS, NWM, NWS 41,2 – 110,0 3,1 50 – 100 *KN, KM, KS is a knitted textile liner web of natural, manufactured or synthetic fibers; NWM, NWS is an non-woven textile liner web of manufactured or synthetic fibers.

Which solute atoms can diffuse to the alloy surface through the grain boundary reaction with the oxygen has an important effect on the composition of the oxide film.
The vacancy and grain boundary in the oxide film provide a short-range material diffusion channel, in which Fe2+ and Ni2+ are diffused outward and oxygen is diffused inward.
After the formation of spinel oxide, it hinders the continuous diffusion of oxygen, limits the movement of some defects (such as vacancies) in the oxide film, reduces the number of defects in the oxide film, and improves the protection of the oxide film.