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In steelmaking, its strong affinity for sulfur is crucial; it forms manganese sulfides, preventing the formation of detrimental iron sulfides at grain boundaries and thus improving the hot workability of steel.
Property Value Atomic Number 25 Atomic Mass 54.94 u Electron Configuration [Ar] 3d⁵4s² Density 7.21 g/cm³ Melting Point 1246 °C Boiling Point 2061 °C Crystal Structure Alpha-BCC, Gamma-FCC Oxidation States +2, +3, +4, +6, +7 Electrical Resistivity 144 nΩ·m Thermal Conductivity 7.8 W/(m·K) 3.
This produces highly refined, often non-equilibrium microstructures with fine grains, leading to superior strength and ductility due to the Hall-Petch effect.
This results in coarser microstructures with larger grains and more elemental segregation.
For example, studies on high-manganese steel have shown that DED produces relatively low yield strengths (~115–149 MPa) due to large grain sizes.

., surface roughness, and crystal grain size distribution), since the displacement was small.
However, the results of the general micro–indentation test were affected by the microscopic scale of materials (e.g., surface roughness, and crystal grain size distribution).
Acknowledgment This study was supported in part by JSPS KAKENHI Grant Number 25709004.

According to the actual PDP in Qiqihar Railway Rolling Stock Company in China, the process for the grain rolling stock development is analyzed and improved, and the result is satisfactory.
In a local sub-iteration, the design activities are implemented serially, but in total they are concurrently done, i.e. concurrent design can be expressed by the addition of many components and sub-iterations [5]: ∑∑== = n 1i ij m 1j onSubIterati Design Concurrent Where, i is the serial number of sub-processes and j is the serial number of components.
(d) To introduce the mechanism of feedback, which feeds back the backward design result to the forward activities to evaluate and modify the design, and change the large design cycle into small one, that is, it can improve the quality and efficiency of design to increase the number of the small cycle instead of the large one.
The Product Development Process of Railway Rolling Stock In the application of the Chinese National 863/CIMS Project 'Concurrent Engineering for Product Development of Railway Rolling Stock', the process for the grain rolling stock development is analyzed, modeled, improved and reengineered, and the result is satisfactory.
The advanced design technology is used and the concurrent iteration and pre-release are added to increase the number of small cycle and decrease that of the large one, and the multi-disciplinary product development team is set up.

The morphology of obtained samples changed from hexagonal rods to discs shape and grain sizes increased with the increase of doped Co in SrFe12O19.
Both SrFe12O19 and SrCoFe11O19 ceramics had the hexagonal ferrite structure corresponding to JCPDS file number 33-1340.
In addition, larger grain size also contributed to the reduction of coercive force.

In this modeling, the inhomogeneous rock is generated by using Weibull parameters which are related to the microstructural properties determined by crack size distribution and grain size.
A summary of a number of test programs and their relevance to underground tunneling has been produced by Martin (1997).Increasing the confinement prevents the initiation of the primary tension fracture and failure is due to the remote and slabbing fractures (Carter 1992; Ewy and Cook 1990a, 1990b).
And simulated AE results plotted between AE counts and load steps are given in Fig.3 using RFPA (Realistic Failure Process Analysis) code. 0 1000 2000 3000 4000 5000 6000 7000 8000 0 50 100 150 200 250 St eps Load/ N ( b) ( a) ( c) 0 100 200 300 400 500 600 700 800 900 1 17 33 49 65 81 97 113 129 145 161 177 193 St eps Load ( a) ( b) ( c ) Fig.2 Simulated stress-strain curve of three specimens (Y-direction) in Fig.1 Fig.3 Simulated AE results plotted between AE counts and load steps In our modeling, the inhomogeneous rock is generated by using Weibull parameters which are related to the microstructural properties determined by crack size distribution and grain size.

In the past 15 years a number of research programmes have been executed, which included the experimental and numerical assessment of the residual stresses around dissimilar metal multi-pass piping welds.
Specimen rocking about the specified measurement location by ±2 mm was applied to improve grain statistics.
Obviously the measurements in the weld materials are compromised by grain size type effects and by the lack of availability of reference coupons.
In the fusion zone measurements were performed with and without rocking of the specimen in order to establish whether the data scatter caused by the large effective grain size and the texture distribution could be reduced.
The data obtained suggested that the data scatter might be reduced by rocking, however a higher number of measurements and – again – a suitable reference specimen would be needed to derive more robust conclusions.

The discovery of an alloy that may exhibit ideal strength in bulk is exciting from a fundamental perspective, and has generated research in a number of laboratories.
An alternate hypothesis for the strength-limiting mechanism in Gum Metal is a stress-induced martensitic transformation to the orthorhombic a” phase that is found in a number of Ti alloys.
As determined by EBSD analysis, while almost all of the crystals in the severely worked sample have <110> axes parallel to the swaging (normal) axis, the grain orientations in the plane that contains the swaging axis are nearly random, and the grains themselves are severely distorted.
The crystal planes of these grains are bent and puckered around the <110> swaging axis.
If the function B(e) is relatively soft, that is, if it does not change dramatically with direction, e, then the precipitate plates can lie in bent or puckered grains with little cost in energy.

Tab.1 Calculation parameters of Shanghai Expressway typical structure Structural layer Materials Thickness /m Modulus /Mpa Poisson's ratio Unit weight /kN•m-3 AC layer SMA 0.04 1400 0.25 24 Medium-grained asphalt concrete 0.05 1200 0.25 24 Coarse asphalt concrete 0.06 1000 0.25 24 Base course and Subgrade Three slag 0.45 1500 0.15 22 Two lime 0.20 750 0.20 18 Soil base 40 0.35 18 Tab.2 Calculation parameters of Shanghai Freeway typical structure 1 Structural layer Materials Thickness /m Modulus /Mpa Poisson's ratio Unit weight /kN•m-3 AC layer modified asphalt SMA-13 0.04 1400 0.25 24 AC-20 0.06 1200 0.25 24 AC-25 0.08 1000 0.25 24 Base course and Subgrade Roadbed Fly Ash 0.45 1500 0.25 20 Gravel 0.15 200 0.27 22 Soil base 40 0.35 18 Tab.3 Calculation parameters of Shanghai Freeway typical structure 2 Structural layer Materials Thickness /m Modulus /Mpa Poisson's ratio Unit weight /kN•m-3 AC layer modified asphalt SMA-13 0.04 1400 0.25 24 AC-20 0.06 1200 0.25 24
Comparative Analysis the Calculation Results with the Measured Results An expressway has beginning pile number K49+000 and end pile number K50+860.
Embankment height of the expressway is 3.5 m, the surface layer from top to bottom respectively are 4cm fine-grained graded asphalt concrete, 5cm medium-grained graded asphalt concrete and 6cm Coarse-grained graded asphalt concrete.

Leading sheet producers have often tried to examine properties of thin packaging sheets with the structure analysis of material (shape and size of grain, configuration of impurities and so on).
Fig. 8 Values of yield strength obtained with the uniaxial tensile test in the direction 0° and in the direction 90°, biaxial tensile test and springback test Fig. 9 Values of tensile strength obtained with the uniaxial tensile test in the direction 0° and in the direction 90° and biaxial test Fig. 10 Values of elongation A50 obtained during the uniaxial tensile test in the direction 0° and in the direction 90° and the elongation obtained with the biaxial tensile test From the results of the individual tests, it can be ascertained that the specimens number 94, 97, 72, 90 (Fig. 11) taken in the direction of rolling had values of yield strength obtained with the uniaxial tensile test a lot higher than the specimens number 13, 18, 91 a 22.
In the Fig. 11c, it is observable that the impurities have shown themselves in their entirety and they are placed mainly on the boundaries of grains.
During biaxial tensile test, there are more appropriate conditions in the grains for yield than there are in the grains during the uniaxial tensile test.

A large number of alumino-thermic rail welds are made in track each year using standard procedures and a very high proportion are reliable [3], however, some do fail.
Whatever the weld type is A or B, there are three successive zones starting from the weld centerline to the molten / base metal interface: a zone with equiaxed grains in size up to 1 mm, then a columnar region and finally, an area composed of small equiaxed crystals at the cold interface.
Then, the weld solidification leads to pearlite lamellae formation with ferrite at grains boundaries (Fig. 2).
The MZ/HAZ boundary is strongly marked by a refinement of pearlitic grains at the HAZ (Fig. 3).
The validation of a fatigue test result requires a large number of specimens.