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Overall, the effect of fine Cr carbides on grain boundary mobility in the LC-Cr steel causes variations in recrystallisation kinetics, grain morphology and micro-textures.
With greater annealing times nuclei also form in grain interiors on deformation defects such as in-grain shear bands.
Similar to the annealing of WR Cr-alloyed LC steels [8], the significant numbers of relatively coarse cementite and alloy carbides aligned parallel to the RD (Fig. 2 and [6]) become nucleation sites during later stages of recrystallisation in both steels.
In both steels the boundary misorientation of recovered grains shows a slight increase in HAGBs compared to deformed grains after 3s (LC) and 16s (LC-Cr) annealing (Fig. 4).
While the g-fiber of nucleated grains in both steels are of similar strengths, the peaks of growing grains in LC-Cr steel are weaker and have a larger orientation spread.

Theoretical analysis Fig. 1 the heat source position From micro view, a large number of the grains rub and cut the surface of the workpiece, causes the grinding heat.
There are three heat source positions around the grain.
They are in the grain-workpiece (wear plane), chip-workpiece (shear plane) and chip-grain interfaces, as shown in the Fig. 1.
vs vw grain The chip and grain interace chip C D A B The grain and workpiece interface The chip and workpiece interface The heat generated in grinding process can be expressed as following: tot w sh gc q q q q = + + （1） Comparing with heat generated in grain-workpiece and chip-workpiece interface, the heat generated in chip-grain interface is so small, so it can be ignored.
The heat partition between the grain and workpiece interface.

Such ingots can have an as-cast microstructure with grains 2-4 cm in diameter and 20-40 cm in length.
The measured hardness was lower on grain boundaries (80HB30) and higher on grain body (120HB30).
This is a dependence on routes number of Bc rotating mode as the full numbers of rotation are 4, 8 and 12.
By passes number increase the GS was decreased and dislocation density was increased, respectively.
Kommel: in Ultrafine Grained Materials III, Ed.

Analysis method of the samples.Two types of castings after heat treatment are processed into the desired size and shape for experiment, then proceeding the analysis of metallographic structure, grain size and the type, number and the distribution form of nonmetallic inclusions.
The microstructure and the austenite grain boundaries of the experiment steel without refined treatment is shown in Fig. 2.
And the microstructure and the austenite grain boundaries of the experiment steel with refined treatment is shown in Fig. 3.
Tab. 4 Content of O, H , N , P, S in steel sample number O(ppm) N(ppm) H(ppm) P(wt%) S(wt%) Refined treatment r1# 2 34 <1 0.024 0.002 r2# 2 35 <1 0.023 0.003 unrefined treatment ur1# 65 100 <1 0.034 0.014 ur2# 63 110 <1 0.032 0.023 Observing the metallographic photographs amplified to 100 times of the experimental steel with and/or without refining we could find that the number of inclusions is in the refined steel has decreased, and the inclusions become more rounded.
The change of these two aspects reduces the number of the potential crack sources and reduces the block function on dislocation motion when the experimental steel happens to plastic deformation.

The grain size increased dramatically in the center of fusion zone and the grain grew perpendicular to the fusion line at the boundary of the fusion zone that compared to the base metal.
The coarse grain zone of the base material was near the interface to the fusion zone.
Adjacent to the coarse grain zone was the fine grain zone.
Lower the heat input by means of increasing the welding speed conduced to the reduction of grain size in the fusion zone and coarse grain zone, which was beneficial to the improvement of the microstructure of the joint.
HAZ FZ BM Fig.5 Microhardness profile of the joint Table 4 Welding parameters used in the experiment Sample number 1# 2# Tensile strength(Mpa) 280 301 Summary A good appearance and defect-free joint of QCr0.8 bronze can be obtained by electron beam welding.

a) Band contrast EBSD map of the microstructure of a titanium stabilized 409 ferritic stainless steel after cold rolling to 50% reduction followed by annealing at 750oC for 200s illustrating the unrecrystallized bands (numbered 1,2 and 3) of a-fibre oriented grains.
(1) Growth of the recrystallizing grains within the deformed a-fibre grains occurs concurrently with 1) recrystallization by “nucleation” of new grains within a-fibre regions and 2) growth of recrystallized g-fibre grains into the still deformed a-fibre grains.
One assumption is that planar growth (eqn. 2) controls the growth of g-fibre grains into a-fibre grains.
Unlike the JMAK model where continuous impingement of grains is assumed, in phase field simulations consisting of a limited number of nuclei, impingement does not commence until a significant fraction recrystallized has been achieved.
Thus, in the phase field simulations prior to impingement the fraction recrystallized varies as [14], (6) where is a geometric constant, is the number of nuclei per unit volume, is the (constant) rate of interface migration and n is the growth exponent, which for site saturated nucleation is the same as the JMAK exponent.

Although surface hardness of SFAP is decreasing with grain size number increasing, surface hardness of SFAP in different grain size is no evident distinction.
While in the same 65 wt% abrasive weight percent, Young's modulus of SFAP is decreasing with grain size number increasing, as Fig.8 shows.
Under the same load, it causes the number of the surface grains of SFAP increases escaping from SFAP.
And with the same abrasive weight percent, shear strength of SFAP is decreasing along with grain size number increasing.
Under the same abrasive weight percent, Young's modulus of SFAP is decreasing with grain size number increasing. 2.

Permanent mold cast (PMC) AJ62 magnesium alloy exhibits a fine-grained microstructure in the thin section and a coarse-grained microstructure in the thick section.
The corrosion behaviors in the fine- and coarse-grained AJ62 alloys were compared.
Integral to an alloy’s adaptation to a new process is the characterization of the alloy’s performance in a number of potential environments.
The chemical additions used, and number of them, also vary from one coolant producer to another and are not information readily disclosed.
The fine microstructures are found to form in the thin section of the casting due to a high cooling rate while the coarse grains are present in the thick part.

As the ratio of the average diameter of fine grains to that of coarse grains is increased, the yield strength of the bimodal structure is decreased.
These properties come from different deformation behavior of fine and coarse grains.
The FE polycrystal plasticity analyses were made on several bimodal structure models which have different volume ratios of coarse to fine grain size dc/df and different volume fractions of coarse grains Vc.
The equivalent stress in the bimodal structure tends to be concentrated in the fine grains near the coarse grains but the number of grains where the stress is high is decreased.
These results imply that the coarse grains in the bimodal structure may relax the stress and strain in the fine grains and thus bring about higher yield strength and relatively higher ductility of the bimodal structure.

Fine spherical grain in the semi-solid 9Cr18 slurry can be obtained at α=45°and L=600mm, the major grain equivalent diameters are less than 55μm and more than 40% of the grain shape factor is in 0.75, exhibiting better grain fine degree and roundness.
Compared to forging operations, however, SSM would reduce the number of processing steps to one single forming operation, a reduction in energy input, and an increase of component complexity.
Here, A expresses the area of measured crystal grain; L expresses the average length of measured crystal grain.
D expresses the size of the grain; the smaller the value of D is, the smaller the grain is.
Fine spherical grain in the semi-solid 9Cr18 slurry can be obtained at α=45°and L=600mm