Search results

All the three mechanisms are determined by the temperature field which is influenced by geometry of workpiece, laser spot diameter, scanning velocity, scanning number and path, etc.
A large number of research works on macro workpieces have been carried out.
Size effect and MSG theory As laser bending sheet size becomes small to a microscale, the material behaviour in micrometal forming differs from that in conventional forming because of different factors, such as the grain size.

The magnetic pressure, created by the inductive current pulses or oscillations can be approximated as: ( ) 2 2 2 2 0 2 sin 2 Rt L K n U C t e P LI µ ω   −    = (1) where µ0 is the magnetic permeability (in H/m), K is a coefficient depending upon the physical dimensions of the coil, n is the number of windings of the coil, ω is the LC oscillation frequency, R is the total resistance of the discharge circuit (in Ω) and t is the time (in s).
From the peripheral elongation with different discharge energy diagrams at varying static pressures, it is explicit that at about 10KJ, the initial static would not have any effect on overall elongations. 0 5 10 15 20 25 30 35 0 1 2 3 4 5 6 7 8 Ps=0 MPa Ps=20 MPa Ps=40 MPa Ps=60 MPa Peripheral elongation (%) Energie (kJ) 1 2 3 4 5 6 7 8 -10 0 10 20 30 40 50 60 70 5 % 10 % 15 % 20 % 25 % Energie (kJ) Ps (MPa) Fig. 7 - (a) Peripheral elongation versus discharge energy for different static pressures, (b) constant elongation curves in Pressure-Energy diagram The metallographic structure of grains is not significant except near the sharp change of curvature of the tube (point 2) in the expansion region (Fig. 8.a).
a. b. 100 120 140 160 180 200 220 240 1 1,2 1,4 1,6 1,8 2 1 2 3 4 5 6 7 Hv Post forming thickness (mm) Initial thickness (mm) Hv Initial Thickness (mm) Point number Fig. 8 - (a) Optical micrographs of deformed tube (Ps = 40MPa and E = 8kJ), (b) Hardness and post forming thickness Conclusions From this short technical presentation of high speed forming work under progress, some of the main features may be described.

Orthogonal test group are shown in table 3: Table3：Grouping test table The test number 0mm～0.075mm（%） 0.075mm～5mm（%） 5mm～10mm （%） 10mm～20mm （%） 20m～31.5mm（%） Water （%） SF3 3 22 15 25 35 According to the situation SF5 5 20 15 25 35 SF8 8 17 15 25 35 SF12 12 13 15 25 35 2.The research of the basic characteristics of graded crushed stone frost heave 2.1 The effect of fine powder content on the frost heave of graded crushed stone Different fine power content of frost heaving experiment results are shown in table 4: Table 4 Different fine power content of frost heaving experiment results SF12 SF8 SF5 SF3 the water mass fraction（%） amount of frost heave （%） the water mass fraction（%） amount of frost heave （%） the water mass fraction（%） amount of frost heave （%） the water mass fraction（%） amount of frost heave （%） 8.036 1.680 7.669 1.378 9.319 0.919 9.416 0.576 7.213 1.316 6.222 0.913 6.941 0.629 7.138 0.517 6.596 1.068 5.544 0.785 5.380 0.496 5.575 0.399 5.786
with the increase of fine powder content.According to the results of the test, different fine powder content of frost heaving ratio’s relationship with the water mass fraction is shown in fig. 2 Fig. 2 The relationship of different fines content rate of frost heave with the water mass fraction In Fig.2,we can see that the relationship of quality moisture content and the rate of frost heave is linear.And different fines concent has their own initial moisture content of frost heave.When the frost heaving ratio is 0, the moisture content is the initial moisture content of frost heave. 2.2 The curve of frost heaving ratio along with the change of temperature With different powder content of graded crushed stone under the condition of the filled with water, the frost heaving ratio under different temperatures is shown in table 5: (o(C)温 度 组 别 Table5 The frost heaving ratio under different temperatures tempe frozen-heave (oC) factor (%) test number
[4] Wang Zhengqiu.The impact of the grain size composition to the frost heave of fine sand[J].

In 1997, they developed a "reinforced concrete structure, Ningbo, concrete mixing with sand rust inhibitor prepared a number of provisions."
process should be careful to prevent sample loss . 3, again adding to the container with water and repeat the operation to the visual clean water container up. 1.1.2 Analysis of test results Table 1 Determination of sea sand in the clay content data Clay content /% a b c d Average Dilute the sand (on) 0.046 0.053 0.42 0.59 0.05 Dilute the sand (below) 0.185 0.172 0.164 0.179 0.175 Not dilute the sand (on) 0.74 0.78 0.62 0.86 0.75 Not dilute sand (below) 0.95 0.92 0.96 0.89 0.93 Data from the table1 and change can be seen that two points, first is a pile of sand with either dilute or not dilute, the lower the amount of sand clay is much larger than the upper sand clay content, analysis of the reasons is due to sea Sand moisture content during the time of stacking large,The second point is not dilute the amount of sea sand in the mud far greater than the diluted sea sand clay content analysis that the sand washed in fresh water during the process of desalination of sea sand in a large number
Analysis, although some fine sand in the shell powder desalination process would be washed away with fresh water, but the sand grains in the shell film is generally more dominant in terms of quality, so the sand content in the data on the performance of shell for the differences small.

It was shown that the higher sintering temperature of SE gives the lower number of reaction sites at the triple-phase boundary (TPB) among gas, YSZ and NiO and brings about low catalytic activity to the heterogeneous gas-phase NO2 decomposition reaction.
The lower number of reaction sites and the lower gas-phase catalytic activity were reported to be responsible for highNO2 sensitivity when the sintering temperature of SE was high.
Fig. 4 shows the representative SEM images for the surfaces of the fabricated NOx sensor (a) surface of NiO electrode, (b) ZrO2,(c) cross-section between NiO and ZrO2, (d) Pt electrode, It is clearly seen that NiO sensing electrode is composed of well-defined NiO grains and porous structure.SEM observations also revealed that there is no interaction between the NiO powder and YSZ plate even after sintering at 1400 ◦C. the interface between the NiO-SE and YSZ is assumed to be chemically stable and composed of NiO and YSZ without the formation of any secondary phases.

Apart from a large number of investigated phosphors, only a few of them can be exploited in practice and covalent nitride compounds are assumed as the most attractive ones because of their plentiful emission colors, high quantum yield and low thermal quenching.
The grain size and morphologies of the samples were observed by a Hitachi 3400N scanning electron microscope (SEM) operated at 25 kV.
Since the photoluminescent (PL) properties and QY do not correlate directly with the purity of the phase composition, the silicon/aluminium ratio or particles morphology it is clear that the observed variation in the PL properties must be related to a number of Eu2+ ions successfully placed in the appropriate Ca2+ sites of the Ca,Eu-a-sialon structure.

There are many facets source region, the expansion area is along the grain characteristics and the final fracture zone is characterized by cleavage.
At the interface of the layered structure, there is a large number of micro-defects[4].
When the cracks extended the solder alloy layer and the substrate interface, there were two possibilities to be considered: if there were a large number of microscopic defects between the interfaces, the combination of the solder alloy bonding layer and the substrate would be weak, and it would form an interface crack, leading to the lamination between the solder alloy layer and the interface layer, even peeling; while if the interface had less microscopic defects, the combination of the solder alloy layer and the substrate would be stronger, the part can be seen as a notched specimen, the matrix at the part would generate stress concentration, resulting alloy layer deposited weld cracks within the matrix through the interface into the fracture [6]

Prediction of blast pressure Blast wave parameters for conventional high explosive materials have been the focus of a number of studies from 1950’.
The fragmentation debris can be analyzed in terms of the shape parameter, which is the ratio between grain length and width.
Therefore, to simplify the analysis, a number of assumptions related to the response of structures and the load has been proposed and widely accepted.

North temperate continental monsoon climate Forest, grain Tonghua More than 2/3 of the area is mountainous, basin topography humid continental climate Forest, drugs, mineral 4.1.3 City Syntax The space integration shows different features in evolution of the empirical urban space axis and their intricate miniature structure reflects the richness and diversity of texture space.
The four cities are surrounded by rivers, and the main hydrographic features are showed below: 4.2.2 Hydrographic Feature Analysis The four cities are connected by roads, and the main traffic features are showed below: 4.2.3 Roads Elements framework analysis Table 4 Traffic Feature Table 3 Hydrographic Feature City The pattern of urban roads Number of Highways Tonghua four horizontal and one vertical 2- Huadian a one-hour economic circle of Jilin and Changchun two-hour economic circle 2 Dunhua four vertical three horizontal and a ring 1 Jiaohe seven vertical and six horizontal, both inside and outside the ring 2 City rivers The cities was divided into several parts River naviga- tion capacity Tonghua Hunjiang 4 Good Huadian Baishan Lake, Hongshi Lake, Songhua Lake 2 General Dunhua One River and 17 Creeks, Mudanjiang 3 Good Jiaohe Most rivers are of the Songhua river system, a small number of rivers of Mudanjiang river system. 3 Good 4.3 Urban Spatial

One of the most important hardening mechanisms in concrete is the junction with bridges between aggregate grains.
Lubricator Number of tested specimen [pc] Number of successful tests [pc] Success [%] Oil 25 4 16.0 Wax 30 12 40.0 The influence of the chosen form lubricator to the results The influence of the chosen form lubricator markedly influenced the amount of the caverns in the specimens and it had a definite action on the tests.