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Introduction In a previous papers [1-6] the intergranular hydrogen embrittlement (IG-HE) of solution annealed types 304 and 316 austenitic stainless steels was explained in terms of the formation of α`-martensite serving as an obstacle for grain boundary sliding (GBS), and the enhancement of GBS was attributed to the diffused hydrogen, which also known as HELP (hydrogen enhanced local plasticity).
The α`-martensite serves as an obstacle for dislocation movement on the slip plane as well as grain boundary sliding (GBS) for IG-HE.The α`-martensite does not self-destruct, even if it grows with enough thickness.
The number of the pile-up dislocation at crack tips (ntip) is composed of napp caused by σapp and nadd by σadd during α`-martensite formation, ntip = napp + nadd (5) The napp is constant (d napp/dt = 0) under the constant applied stress condition.
In addition, Ltip is also composed of Lapp caused by σapp and Ladd formed during α’-martensite formation, Ltip = Lapp + Ladd (8) where Lapp is constant, dLapp/dt = 0, and then during α`-martensite formation dLtip/dt = dLadd/dt (9) Furthermore, a concentrated tensile stress, corresponding to σtip, is expressed as, σtip ∝(τ – τi)(Ltip/r)1/2 F(φ) (b << r << Ltip) (10) where r is the length from the tip of the pile up which corresponds to a hydride thickness at crack tips, and F(φ) is a function of φ that is the angle between planes in adjacent grains.

The FESEM micrograph in Fig. 2(a) show that the ZnO films have a uniform grains.
The undoped ZnO have a grain size around 20 nm as shown in Fig. 2(a).
Excitonic peaks from absorption spectra (Fig. 3(b)) can be observed for undoped ZnO which indicates the number of defects is reduced and the quality of the films is improved.
The photoresponse at 1 at% is the highest and the photocurrent decreased at 2 at.% which can relate to the excess Al that produced defects from the formation of stresses due to the ion size differences between Zn and Al and the dopants segregation in grain boundaries for higher doping concentrations.

For Z/A#3, no wear debris was observed after a number of cycles of 1×10 4, afterwards, a rectangular shape of wear track was formed, and wear debris were generated as test duration continued, but the amount of wear debris was relatively less than that from Z/A#2 for each test duration.
It seems that even though its global fracture toughness is lower than the other Z/A composites, the addition of zirconia to alumina (80%), which has a drawback of grain boundary failure, improve the microscale fracture toughness.
From the morphological observation on the wear track by a scanning electron microscope, some damage such as grain loosening followed by grain boundary cracking, pitting, and large scale crack for each Z/A composite, respectively (Fig. 5).

In this study, the grinding wheel was flat form, 9 mm in diameter, 10 mm thick and 4 mm in inner diameter; it was a ceramic bonded, 200-grain-size, K-grade CBN grinding wheel.
As coolant existed in the interface between the work piece and the abrasive grain, the frictional coefficient between them was decreased.
First of all, wear and loading occurs in abrasive grain, due to excessive friction force in a nearly dry grinding process.
Acknowledgement This work was partly supported by JSPS KAKENHI Grant Number 25289012.

Recently aluminum industry, refractory and abrasive needing for high-grade ore, causes our bauxite resources of rich ore is more and more barren, and a large number of crushing and low-grade ore is idle, which causes a serious wasting of resources [2].The development of bauxite-based homogenization grogs will be an effective way to realize comprehensive utilization of resources [3-4].Bauxite-based homogenization grogs are based on natural raw bauxite as main raw materials, after homogenization, through the forming, calcination technology to prepare refractory raw material, and comparing natural raw material, the prepared refractory raw material has the characteristic such as mineral stability, uniform composition, consistent compactness [5].
So 70 green sample's bulk density that holding for 4h at 1600°C is better, and continuing to extend the heat preservation time failed to achieve sintered sample's bulk density increasing, which is likely due to the abnormal growth of crystal grains.
Appropriate heat holding time can eliminate porosity; promoting the grain boundary migration and grain growth, so as to improve its density.

In this notation, A represents a mono-, bi- or trivalent ion, B denotes a tetra-, penta- or hexavalent ion, and m is the number of BO6 octahedral in each pseudo-perovskite block (m = 1,2,3,4,5) [9].
The shape of grains was plate-like morphology, and the grain size increased with the increasing x.
SEM showed that the shape of grains was still plate-like morphology.

A powder of abrasive and ferromagnetic grains is dispersed on the magnetic disks.
Fig. 1 Equipment for the magnetic finishing of cutting tools Due to the kinematic overlapping of these movements, the abrasive grain flows over the surface of the tool, which leads to a polishing of the tool surface and to a rounding of the cutting edge.
Several process parameters have an influence on the process result [3, 4, 5]: • Distance between disk and tool • Process time • Tool material • Grain size of the abrasive powder • Amount of ferromagnetic powder • Rotating speed of the tool • Rotating speed of the magnetic disks • Position of the tool between the magnetic disks The geometry of the cutting edge can be described by the cutting edge sections Sα, Sγ and ∆r and by the section ratio Κ (Fig. 2) [5].
The tool diameter is d = 16 mm and the number of teeth is z = 4.

Diamond abrasivetool Fig.1 Pneumatic face grinding tool with planet structure According to preparative workpiece size, the number of pneumatic motor and diamond wheel with spring jaw can be chose 2~4 sets.
So it avoids chip to stem space of abrasive, processed surface roughness of workpiece to be Outflow of cool water Fig.2 Processing workpiece with grinding tool The entrance to coolant Tool shank Diamond abrasive layer Workpiece destroyed by fall-off abrasive grains and restrains high grinding temperature. 3) The self-sharp character is that new abrasive grains are produced when abrasive grain is dulled during the grinding process.

The current material is having primary alpha grains and bi-lamellar colonies comprises of α and transformed ß.
Results and Discussion Fig.2 shows the basic microstructure of investigated Ti-6Al-4V alloy which has bimodal microstructure consisting of primary α grains and lamellar colonies of secondary α and ß.
The volume fractions of the α grains and the α+ß colonies are identical.
Acknowledgement This work is partly supported by the Structural Materials for Innovation of the Cross Ministerial Strategic Innovation Promotion Program (SIP) of Japan Science and Technology (JST), and JSPS KAKENHI Grant Number JP15H04147.

This stage is usually most of the switching process of the fatigue break.2) cracks on the interface: the dislocation set to a certain extent, will reduce the strength of the interface, the formation of separation, thereby generating cracks. 3) cracks on grain boundary: under the cycle of the stress, the stress concentration at grain boundaries was not slack. when the stress peak will be increasingly high and the grain boundary strength is exceeded, the crack is formed.4）cavity formation and cracks by connection
The fracture was detected and the rotation number of the bearing was recorded by vibration sensors and hall elements.