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There is a constant need for production engineering developments ranging from purity degree - that is producing molten metal with high cleanness - to grain refinement and alloy improving including heat treatment technologies.
Figure 1: Hardness depending on different heat treatment parameters Table 2: Standard deviation of the hardness results - depending on different heat treatment parameters Serial number of the different heat treatments SD 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.
Figure 2: Tensile strength depending on different heat treatment parameters Table 3: Standard deviation of the tensile strength results - depending on different heat treatment parameters Serial number of the different heat treatments 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.
Figure 3: Elongation depending on different heat treatment parameters Table 4: Standard deviation of the elongation results - depending on different heat treatment parameters Serial number of the different heat treatments 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.

Theoretical Analysis Titanium has been widely used for thinning grains.
The formation of TiO2 micro-inclusions decreases the number of [Ti] which should be used to combine [C] or [N], and increases the number and size of complex oxide by providing basis for heterogeneous nucleation.
Either deep deoxidation or strictly controlling the mass of Ti-Fe alloy added into steel through measuring dissolved oxygen content online would be effective methods to decrease the number and size of Al2O3-TiO2 complex oxide and TiO2 simple oxide.
It would be available for decreasing the number and size of micro-inclusions to control the number of wTi·wO2 less than 3.96×10-08 before steel begins solidification through certain methods.

We performed a few test for each loading ratio, which facilitated studying of a great number of cracks.
During fatigue we measured by means of strain gauges the change of strain as function of number of cycles in the area of micro cracks.
The number of cycle's waried from 0 to 280.000 where the test was stopped.
The data on this lining are: deformation optical constant F = 4,10x10 -6 m/rad, module of elasticity E=2900 MPa, Poisson's number n=0,36 and thickness of lining h=2 mm.
From fractography we can establish that the crack length-number of cycle's ratio is not a continuous smooth. 2.

Results and discussion Fig. 3 shows the S-Nf curves (Nf: number of cycles to failure).
As seen from the figure, in the process of propagation in tensile mode, the relation between the logarithm of crack length and the number of cycle was approximated by a straight line, meaning that the crack growth rate is proportional to the crack length.
S-Nf curves 10 4 10 5 10 6 0 50 100 150 200 250 糫 糫 S-Nf curves RH25% RH85% Strees amplitude, 〉a MPa Number of cycles to failure, Nf cycles Fig. 5 shows the crack growth rate against for the term σanℓ.
The reason may be explained from that a crack of the present alloy initiated at the early stage of fatigue life even in low humidity as mentioned above, consequently the effect of humidity on the crack initiation was very small. 0 1x10 5 2x10 5 3x10 5 4x10 5 5x10 5 6x10 5 7x10 5 0.01 0.1 1 10 Coalescence of cracks Crack length, l mm Number of cycles, N cycles RH 25% 220MPa 200MPa 180MPa 160MPa 140MPa 0 1x10 5 2x10 5 3x10 5 4x10 5 5x10 5 6x10 5 7x10 5 0.01 0.1 1 10 Number of cycles, N cycles Coalescence of cracks Crack length, l mm RH85% 220MPa 200MPa 180MPa 160MPa 140MPa Fig.4 Crack propagation curves 10 7 108 10 9 10 10 10 -9 10 -8 10 -7 10 -6 RH25% RH85% 1 1 Crack growth rate, dl/dN m/cycle 絓ー膄絙縕l , (MPa) 5 m Fig.5 Crack growth rate against for the term σanℓ Fig.6 Morphology
zigzag manner being affected by microstructures like a eutectic Si, segregated Si particles, grain!

This is because active site relatively small in system when the concentration of small, the relatively large number of monomer around, easy to generate a large number molecular polyaniline, and acid doping is not sufficient, so when the concentration increase, it generate more and more acid doped polyaniline; When concentration of the acid or oxidant is too high, the sulfosalicylic acid may hinder the polymerization of aniline, and active site relatively much in system, the relatively small amount of monomer around, is not conducive to generating macromolecular polyaniline.
（a）after 64 hours morphology （b）after 124 hours morphology Fig.3 Corrosion morphology of same formulations and in the different time Figure3 are the corrosion morphology of coating by the 64 hours and 124 hours at the same time, the surface of two pictures are coarse, but B1b have small grains, it could be caused by intergranular or pitting corrosion, it can be seen that the corrosion of B1b is more severe than B1a, it because the longer of corrosion time, the greater of corrosion degree.
Fig. 4 After 64 hours morphology in different formulations The figure shows, the number of Black spot and air gap on the surface of E1a and B1a is more than D2a and C3a, and black spot much big and deep, it can be seen that E1a and B1a are more severe corrosion than D2a and C3a.
Because of the oxidant and dopant acid concentration of C3b formulations is moderate, the number of synthetic molecules is moderate, doped fully and corrosion-resistant of synthetic polyaniline is strong.
Fig.6 The polarization about different samples in 3.5%NaCl solution at room temperature Table3 Corrosion potential and corrosion current parameters of different samples (room temperature) number Ecorr (V) Icorr (A/cm2) logI (A/cm2) B4 ﹣0.8426 1.4197×10﹣5 ﹣4.8478 C3 ﹣0.5548 6.1038×10﹣6 ﹣5.2144 D2 ﹣0.7451 9.6516×10﹣6 ﹣5.0154 From the Figure 6, △Ecorr（C3）＞△Ecorr（D2）＞△Ecorr（B4）that is the highest the corrosion potential of the sample C3.

The microstructure of tested steel is ferrite and second-phase particles, the level of the grains is 7.
Add to the number of movable dislocations did not change more, so BH value no change basically.
Due to the increase of dislocations, the number of "Cottrell atmosphere" is also increased.
This is due to the small strain can make the steel plate produce a small number of new dislocation and formed the "Cottrell atmosphere" with solute atom, so as to improve the bake-hardening value.
It will reduce the number of free dislocation instead and the number of formatting "Cottrell atmosphere" will decrease, so as to reduce the BH value.

The desired final grain size in the product is 35mm.
The optimum ram velocity for achieving the above grain size is found to be 160mm/s when billet temperature is 1080oC.
The measured average grain size was 38mm, very close to the designed value.
This is a first of its kind dual purpose system in the country and has been applied for a number of applications.
Acknowledgements This paper is written based on the innovative ideas and consistent efforts of a large number of dedicated scientists at IGCAR, mostly from the Metallurgy and Materials Group.

Additionally, the elastically scattered peak intensity can be used to map grain structure in multicrystalline samples.
Grain boundary structure from elastically scattered peak.
In addition, the dimensions of a particle smaller than the beam spot size can also be determined: Knowing the depth of an impurity particle (and thus, the attenuation of the exiting X-ray fluorescence), and calibrating the µ-XRF count rate with a standard material with known impurity concentration (typically a NIST SRM 1832 or 1833 foil), it is possible to determine the number of impurity atoms comprising the particle by using the equation: )(cm (atoms/g) )(g/cm [M] (cts/s) (cts/s) =(atoms) 2 Std 2 Std Std Prec Prec A D C C N ⋅ ⋅ ⋅ , [Eq. 3] from Ref. [8], where Nprec is the number of atoms in a precipitate, Cprec is the XRF count rate with the beam focused on the precipitate and adjusted for the depth of the particle, Cstd is the XRF count rate of the standard sample, [M]Std is the known metal concentration within the standard, DStd is the density of the standard material in terms of atoms/g, and A is the X-ray beam spot size.
Oxidation state, degree of covalent or ionic bonding, and coordination number are factors that heavily influence XANES and depend on local bonding.
The operations of the Advanced Light Source at Lawrence Berkeley National Laboratory and of the Advanced Photon Source at Argonne National Laboratory are supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under Contract Numbers DEAC03-76SF00098 and W-31-109-ENG-38, respectively.

The presence of boron nitride, BN, in the coating, which positively effected a reduction in the oxygen content in the molten alloys, resulted in an increase in the number of cases of impermissibly high nitrogen content (Table 1).
These precipitates appeared as clusters at the grain boundaries and small particles inside the grains (Fig. 5).
A visible effect of rolling was the refinement of the grains and precipitates present in the microstructure (Figs. 8b, 9b), and this effect was particularly large in the alloy deformed at a higher temperature (Fig. 9b).
Summary The results of the authors' own previous studies and those conducted in this work on evaluating the possibility of melting titanium alloys in vacuum induction furnaces equipped with metal and ceramic crucibles and coated ceramic crucibles have indicated that the material of the crucible, the material and means of applying the coating, and the number of melts carried out in the crucible dictate the purity of the alloys.
Despite their presence, these alloys can be plastically deformed under multipass hot-rolling processes that produce high overall deformation, which results in considerable refinement of the grains and precipitates present in the microstructure.

Results showed that with increasing Si content martensite got coarsening and the number and content of primary carbide increased; The type of primary carbide was M7C3 and Si mainly dissolved into martensite by XRD analysis; The wear resistance was effectively improved while Si content increased.
It can be seen from the Fig. 3 that carbide grain size was less than 1µm and distributed homogeneously which is helpful to improve the wear resistance when the content of silicon ranged from 1.0% to 2.0%.
Table 2 presented the percentage by weight of carbides extracted from the structure of the specimens and the type of carbides in the structure is shown in the Fig. 4.: Table 2 Effect of silicon content on the percentage of carbides(wt%) Specimen Number 1 2 3 Mass Percentage of carbides 4.23 5.38 5.97 The mass percentage of carbides extracted from the specimens during the same heat treatment was increasing when the content of silicon ranged from 1.0% to 2.0%, as shown in Table 2.
Table 3 The wear volume loss and relative wearability of specimens Specimen Number Wear volume loss V/mm3 Relative wearabilityε 1 0.1103 1 2 0.0679 1.62 3 0.0575 1.92 Table 3 showed the effect of silicon content on the wear resistant of the samples.