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Rapeseed oil was provided by Dantu grain and oil chemical plant, China. -10PD was obtained from China Petroleum & Chemical Corporation.
Table 2 Main chemical composition (wt.%) of RME a RME Content RME Content C14:0 0.33 C16:1 0.44 C16:0 9.35 C18:1 40.33 C18:0 3.51 C20:1 3.05 C20:0 0.79 C22:1 6.95 C22:0 0.49 C18:2 25.25 C24:0 0.22 C18:3 7.38 aCm:n is shorthand of fatty acid methyl ester. m is the number of carbon atom in fatty acid group. n is the number of double bond.
RME was mainly composed of long chain fatty acid methyl esters (FAME) of 14-24 even-numbered C atoms.
To organic compounds with similar composition and structure, substance volatility got poor with increasing the molecule mass (the number of carbon) and molecule 3D-structure.
It was chiefly because -10PD was mainly composed of alkane of 8-26 C atoms, and RME was mainly composed of FAME of 14-24 even-numbered C atoms.

The critical need for use of a scientific approach to optimize plunge depth for a given tool material and test machine in fewer number of steps is emphasized.
The weld nugget (WN) is essentially a recrystallized central portion of the TMAZ and has substantially smaller equiaxed grains than the base metal.
Grains are elongated in the direction of rolling with the size varying from 300 μm to 500μm.
Invention of the FSW process made a number of aluminium alloys, especially the copper containing 2000-series and 7000-series, receptive to welding, which were previously considered to be unweldable primarily because of their sensitivity to cracking due essentially to a wide freezing range during solidification coupled with the formation of partially melted zones in the heat-affected zone near the fusion line.
Further, a higher heat input favours: (i) coarsening of the grains, (ii) an elimination of hardening to a wide range of work hardened materials, and (iii) over-aging in precipitation hardenable aluminium alloys in the HAZ.

Algeria is today faced with an ever increasing problem of providing adequate yet affordable housing in sufficient numbers.
Grain size distribution.
Figure 10 shows the percentage of weight loss with the number of wetting-drying cycles for static and dynamic compaction.
This figure indicates that the weight loss increases with the number of cycles.
Even for dynamic compaction, with an incorporation of 5% cement content, the weight loss evolves according to the number of cycles of wetting-drying.

It is known that when mechanical strain exceeds the irreversible strain, cracks will form at high-angle grain boundaries and cause the degradation of critical current [12].
The samples were numbered 1#, 2#, and 3# respectively.
Parameters of the samples used in monotonic tensile experiment Sample number 1# 2# 3# Critical current Ic0 (A) 158.96 156.43 152.34 Strain 0.485% 0.458% 0.439% Normalized critical current 96% 96% 93% Fig. 2 Normalized critical currents and stress versus strain relation in copper reinforced Bi-2223/Ag (77K, self-field) Fig. 3 Stress-strain curve in copper at room temperature Critical currents versus repetitive tensile stress relation.
The samples were numbered F1, F2, F3, and F4 respectively.
Effect of tensile strain on grain connectivity and flux pinning in Bi2Sr2Ca2Cu3Ox tapes.

Among the advantages of this technique as compared to other tools such as transmission electron microscopy, is the fact that accurate, quantitative numbers can be provided for the characteristics of the precipitate size distributions, measured on a very large number of particles.
Al3Zr precipitates are used as anti-recrystallisation agents due to their ability to pin grain and subgrain boundaries.
Since Zr and Sc atoms have very different atomic numbers, it can be expected that the chemical inhomogeneity inside the precipitates results in a specific small-angle X-ray scattering signal.
Once these parameters are known for a given metallurgical state, the average precipitate composition is known and the precipitate volume fraction fv can be calculated from the integrated intensity Qo : ()2mp 2 o v 2 Q f ρ−ρπ ≅ , where ρp and ρm are the electron densities of the precipitate and matrix and ()∫ ∞ = 0 2 o dqqqIQ is calculated from the experimental data. 0 50 100 150 200012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate radius (Å) 0 100 1 10 -3 2 10 -3 012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate volume fraction 0 20 40 60 80 100 012345678 Time (h) Zr/(Zr+Sc) in the shell (%) 5°C/min 10°C/min 430°C/min 10 100 1000 10000012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate number density (µm-3 ) Figure 5: Precipitation kinetics at 450°C of the AlZrSc alloy, as a function of the heating rate: (a) precipitate size, (b) precipitate volume fraction, (c) composition of the
These features of fast nucleation and slow growth and coarsening enable to obtain a remarkably stable microstructure of fine Al3(Zr,Sc) dispersoids, which have proven to be very effective in controlling the grain size of many Aluminium alloys.

In terms of nucleation and growth, when a layer is cooled to 700°C, a large number of fine β-particles nucleate.
This results in a smaller amount of growth of the columnar structure, that results in smaller columnar grains at the top layer.
The martensitic decomposition is a classic “nucleation and growth” process, and when a layer is cooled to 700°C, a large number of very fine β-particles nucleate.
The regions close to the upper edge are the last to be printed and hence are subjected to a lower number of reheating/cooling cycles.
The less repeated heating results in a lower amount of growth of the columnar structure, and subsequently smaller columnar grains on the top layers are obtained.

The addition of TiC significantly improved the grain size and enhanced the strength of the composites.
The composite samples treated for 1 hour followed by aging for 2 hours also have a higher number of precipitates than the samples aged for 1 hour only [17].
Hybrid matrix composite compositions utilized in this investigation Composite Number AA6061 wt% TiC wt% Mos2 wt% 1 100 0 0 2 89 8 3 3 88 10 2 Fig 1.
This is due to the formation of fine grains of aluminum and magnesium precipitates in the composite, which allows to resist plastic deformation under different loads and sliding distances better.
Rockwell Hardness number for various composition Composite specimen As Cast Age hardening AA6061 44.3 56.4 AA6061+8%Tic+3% Mos2 59.02 91 AA6061+10%Tic+2%Mos2 63.1 99.3 Fig 6.

The Hardness Number as a measure of the degree of plastic deformation Hardness tests have been conducted for a long time to characterize materials, mostly because of their characteristics (simple, non-destructive, low-cost), as well as for their capacity to assess low-volume mechanical characteristics, [1].
As known, [2], the hardness Number represents a measure of degree of plastic deformation suffered by some materials.
For normal 1C45 (1.053) steel, the graph of Fig. 2a allows the conclusion that high hardness values are registered in the zone where fatigue crack was initiated, which required a significant number of loading cycles, about 120.000.
Vickers hardness increases in the area of the sudden fracture of the specimen (the final zone, with bigger and more brilliant grains), the values registered in this zone occurring within a certain level.
The hardness values are higher in the zone where the fatigue crack is initiated, for which a relatively high number of fatigue cycles are necessary.

When coupled with large and variable grain sizes, the HCP structure has in the past lead to less than optimum mechanical properties.
While the weight savings with magnesium has the potential to be enormous, in comparison with aluminum the tensile strength of magnesium is approximately 25% less, fatigue behavior (number of cycles to failure) is 35% less, hardness 30%, modulus, 40%, and thermal expansion 15% less.
(9) Where cσ∆ and p cε∆ denote local stress and strain of a randomly distributed single crystal while σ∆ and p ε∆ are the overall stress and strain that are considered as the average of the local stresses and strains over all randomly distributed single crystal grains. 1 1 i � p p c i� ε ε ' = ∆ = ∆ '∑
Stress-strain hysteretic loop data were captured following linear increasing cycle number basis at the first 5 cycles.
As observed in Figure 10, the cyclic mean stress mσ decreases with increasing cyclic number N for AM60 with strain amplitude aε =0.3% and R ratio R=0.7 obviously.

In cyclic conditions, the weight gain vs. cumulative cycle number curves showed approximately parabolic behavior at 850 and 950°C.
Cycle number 0 25 50 75 100 125 150 Mass variation (mg/cm²) -2 -1 0 1 2 3 Fe-17Cr-0.4Ti Fe-17Cr Fe-17Cr-0.2Ti Fig. 4.
Number of cycles Fe-17Cr Fe-17Cr-0.2Ti Fe-17Cr-0.4Ti 150 0.7 % 0.23 % 7.3 % 300 0.02 % 0.54 % 3.2 % Oxide characterization.
It was also observed on the cross sections that both reference and low-Ti grades exhibited marked interface undulation, whereas the high Ti grade exhibited a flat interface, except at the locations of grain boundary emergence.
Scale adhesion seemed to be directly linked to chromia scale keying into the steel substrate at locations of grain boundary emergence.