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Nomination Continuous energy input Pulsed energy input Number of pulses: 1 2 Intermediate time: tint (cycle) 0 15 Weld time: tw (cycle) 12 6 Weld current: Iw (kA) 5.75 6.35 Weld voltage: Uw (V) 1.40 1.46 Electrode pressure: Fs (bar) 3 3 Fig. 1 Hardness distribution, spot weld and impact test specimen of the joints of DP 1000 steel examined in the experiment, welded a) with a continuous energy input, b) with a symmetric double pulse b) a) Fig. 2 SEM pictures from the structure of nuggets a) dendrite structure with continuous energy input, b) tempered ring with symmetric double pulse.
In order to capture the correct microstructure evolution, a number of material properties are required for present simulations.
The short time above Ac3 was limited grain growth, producing an ultra-fine structure upon cooling in this region.

The reason was attributed to their chemically homogeneous structure and the absence of grain boundaries, second phases and segregations.
According to Faraday’s law, the corrosion rate, Rcorr, only depends on the corrosion current density, and can be calculated as [18]: (1) Where Aw is the average atomic weight of metal, ρ is the density, z is the charge number which indicates the number of electrons exchanged in the corrosion reaction and F is the Faraday constant.

This is also visible in the high number of papers published on the topic in a substantial number of journals worldwide [1].
M., Synthesis and characterization of high purity, fine grained mullite.

Our previous works on thixo-extrusions of high strength and foundry aluminum alloys, which are difficult to hot-work, at higher solid fractions ( fsolid > 0.85 ) have shown that A7075, A2014, hypereutectic Al-Si-Cu-Mg and Al-10%Mg alloys must have a finely grained or non-dendritic fine structure, in order to obtain excellent thixo-extrudability, good mechanical property and age-hardenability of thixo-extruded products comparing to those of hot-extruded ones [1-4].
As for the cause of higher peak hardness values and also larger age-hadenabities in rheo-extruded bars, i) increase in a degree of supersaturation of solid solution due to rapid cooling from high temeperatures where the liquid phases exist, ii) refinement and increase in number of presipitates contributing to age-hardening, and iii) existence of much higher age-hardenable zones due to segregation of the solute relating to age-hardening may have to be taken into account
It was thought that this poor tensile property was attributable to existence of a large number of micro shrinkage porosities near the primary silicon particles.

Introduction As the Metal Oxide Semiconductor Field Effect Transistor (MOSFET) becomes smaller, the number of atoms in the silicon that produce many of the transistor’s properties is becoming fewer, with the result that control of dopant numbers and placement is more erratic [1].
Arenas et al. [5] used a Taguchi L9 (34) orthogonal array methodology to study the manipulation of steeping time, ratio of steeping water to corn grain, germination temperature and time for the optimization of germination percentage of blue corn.

Dividing all applications into two control classes to manage shim functionality is not nearly fine-grained enough for serious use.
Socket descriptor mapping and socket substitution for lower layers shim control system is a rule object, consisting of an IP address, a subnet mask and two port numbers.
Since network protocols typically have a large number of tunable parameters, the sysctl interface facilitates adjusting system properties without requiring editing of source code and kernel recompilation.

Even the microstructures of metals may contain grains of greater strength and lower strength.
The material parameters for Eq. 1 are given as follows where the stress in MPa and time in hour: E =1.65 x 10 5, µ =0.3, B = 4.263 x 10-16, n = 6.74, A = 8.0385 x 10-10, υ = φ = 4.23, Dcr=0.999 The structures of a number of length ratios have been calculated.
A number of cases are thus computed by assigning the different damage values of Bar 2 corresponding to different times prior to rupture repair.

The test number of each case is five.
Densification of the Ag paste depends on the evaporation of tetradecane, grain growth of Ag particles, and the decomposition of dispersant with increasing temperature and time.
The test number of each case is twenty.

During a stretch forming process, if the elongation rate is too high (i.e. exceeds certain range), then Lüdder lines occur on the appearance of the product in the beginning, and course grains and fracture in the material will be produced as the situation becomes worse; if the elongation rate is less than certain range, then spring back occurs, and as a result the contour of the product can not meet the aerodynamic requirement of an aircraft.
The total element number for the sheet blank is 60 × 30, and the total element number for the form block is 50 × 50, as depicted in Figure 3.

The discontinuous jumps of Bloch walls are due to their local pinning by different obstacles such as inclusions [9], precipitates [10], grain boundaries [11] or dislocations tangles [12].
When the number of these pinning obstacles increases, the Barkhausen noise amplitude increases too.
As it was mentioned before, the Barkhausen noise amplitude (BNA) mainly depends on the number of obstacles met by Bloch walls, that is to say in a first approximation on the proportion of one metallurgical constituent.