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However, the studies mentioned above have been made to study the effect of some parameters that affect the life of the die.
Factors to be considered in this work are material grain flow and forging force and tool stresses, which were then used to determine part quality and tool life.
Material properties, used in the FE simulation, for die insert and die ring shown in Table 1 were taken from reference [14].
The shear friction factor used in the analysis of each step is 0.1.
Table 1 Mechanical properties of die and workpiece Description Material Elastic modulus E [GPa] Poisson‘s ratio Yield stress [MPa] Strength coefficient [MPa] Strain hardening exponent Fatigue strength coefficient [MPa] Fatigue strength exponent Work piece AISI 1015 199.9 0.29 490 784.6 0.1 Die insert 84WC-16Co 470 0.22 2,100 33,145 -0.289 Die ring AISI D2 209 0.3 1,200 Result and Discussion Flow lines from FE analysis, shown in Fig. 3, exhibit that acceptable screws will be produced because the metal grain flow lines follow the shape of the forged part [15].

The transient temperatures generated by grinding and the heat flux produced at the wheel workpiece-interface, are the major factor, which influence surface integrity and phase transformation on the machined surface [2, 3].
In order to simplify the simulation, a 2D FE model is chosen with temperature-dependant thermal material properties for the grinding of high speed steel workpiece.
The involved expansion of the very small heat affected volume of material surrounded by cold material, assumed as rigid, leads to compressive stresses.
A thermo mechanical finite element model shows that residual stresses decrease beneath the surface and it is found out that there is a significant relation between temperature and residual stress.
The next step is to verify the model experimentally .A metallurgical thermo-mechanical finite element will be conducted in order to understand microstructure changes of the high speed steel material and its effects on the presence and the nature of residual stress in the workpiece.

Hardness and toughness have been identified as significant factors effecting cavitation erosion of materials.
Erosion mechanism of steel was mainly plastic deformation, whereas in case of coating, (i) lack of adhesion between splats (ii) lower toughness of alumina (iii) loosely bonded un-melted alumina particles, were dominant factor controlling the erosion mechanism of coating.
Among various types of coatings, cermet coating provide better combination of requirement properties.
The low fracture toughness of alumina seems to be Fig. 4: Resistance against cavitation erosion offered by uncoated and coated steel one of the major controlling factors in the erosion response of the coating.
In present case, lack of adhesion between Ni and Al2O3 splat affected the erosion resistance.

The agglomeration can be affected by two factors, such as instability between particles during the preparation and synthesis process due to increased surface tension between grains in the particles.
The reduction of magnetic domain spins can cause the magnetic properties of iron sand to decrease.
So, it can be seen that magnetic properties such as saturation remanence and coercivity are summarized in Table 2.
Iron sand before and after synthesizing has magnetic properties as shown in Table 2.
Panjan, “Synthesis conditions , structure, particle shape analysis , cytotoxicity and magnetic properties,” J.

In the case of mechanical adaptation the micro-plasticity hysteresis is only observed and for fatigue resistance estimation the models of high-cycle fatigue are applicable.
If there is no mechanical adaptation under cyclic mechanical loading then the macro-plastic hysteresis is observed, resulting in low-cycle fatigue failure with a short service life.
Table 1 Comparison of model (1) predictions with experimental data Exp. № Beam length, m Section height, mm Maximal tension Number cycles before failure Prediction by Eq. 1 Experimental data 1 0.58 68 42 0.0028 100 237 2 0.58 68 50 0.0143 30 24 3 0.27 38 25 0.0184 70 64 4 0.27 38 30 0.0453 32 16 5 0.27 38 30 0.0468 49 16 Influence of Stress Gradient at the Stress Concentration The quality of the surface (roughness, scratches, sharp transitions, edges) essentially affects the behavior fatigue of structures (according [9] data at the depth 0.125-0.22 mm) and attenuates the strength properties.
Firstly this approach was used for determining the notch factor in the case of static failure.
Peterson, Application of stress concentration factors in design, Proc.

It is widely used in the production of new materials that require specific chemical and physical properties [1].
It has been shown [3, 4], that Ni100-xFex, (10properties that lead to widespread use of these materials in variety of applications.
Applications based on the soft magnetic properties include: read-write heads for magnetic storage, magnetic actuators and high performance transformer cores [7,8].
The growth Kinetics of three-and two dimensional (3D and 2D) clusters have been examined by many authors [9,13] and under different experimental conditions accounting for various limitation factors.
Finally, the marked reproducibility of these Ni-Fe alloys needs an extended study of other physical properties.

High manganese steel is widely used in various fields of actual production due to its characteristics of excellent mechanical properties and low cost of production and so on.
Considering the surface quality, hardness, wear resistance and other factors, when the content of Ti+C was 80%, the coating has the optimal performance: the average hardness was 48 HRC and the relative wear rate was 40%.
Microstructure Evolution and Wear Properties of In-situ Synthesized TiB2 and TiC Reinforced Steel Matrix Composites[J].
Effect of Process Parameters on Properties of TiC Reinforced High Manganese Steel.
Microstructure and Properties of Fe–TiC Ceramic–metal Composites[J].

.%) Al Mn Zn Fe Si Be Cu Mg 3.19 0.334 0.81 0.005 0.02 0.01 0.005 Balance Mechanical properties test at room temperature Uni-axial tensile tests at room temperature were carried out with 1.0mm thickness specimens.
The flow stress behavior of AZ31 Mg alloy at low and constant strain rate, and at room temperature can be simplified with the Hollomon equation (see Eq.1), here, K and n are the work hardening coefficient and exponential factor, respectively
(1) The mechanical properties of the material were measured by the stress-strain curve, and shown in Table 2.
Table 2 Mechanical properties of AZ31 Yield stress, σs [MPa] Tensile strength, σb [MPa] n K, [MPa] 183 257 0.184 425.96 Experiments The SHPB tests have been performed with Ф5mm×5mm cylinder specimens on the high-temperature SHPB system of the Northwestern Polytechnic University of China, which was given in Ref.[4].
Flow stress is obviously affected by deformation temperature and decreases with the rise of temperature at a certain strain rate.

Introduction The grinding-hardening is a new technology utilizing heat and mechanical composite effect induced in grinding to quench the surface of steel directly.
Brinksmeier and other scholar proposed this new technology [1], many scholars studied on the grinding-hardening technology, but the relevant research was confined to the aspects such as one-pass surface grinding or cylindrical grinding-hardening, the microstructure and properties of hardened layer at the part of workpiece and the prediction of the hardened layer depth etc [2-11].
This paper was based on surface grinding-hardening experiment, and studied the effects of grinding parameters and grinding method on the organization and properties in the grinding-hardened workpiece of 65Mn steel.
All of these factors caused the heating temperature of the material in the workpiece's surface to be above quenching phase-transition temperature from the cut-in point in reciprocating grinding.
Liu: China Mechanical Engineering, Vol. 15 (2004) No. 17, pp.1573-1576.

Cross sectional area of single filaments, a key parameter to characterize fiber properties, was experimentally studied using a desktop scanning electron microscope.
Introduction Precise measurement of cross sectional area of fiber samples is one of the important tasks in characterizing mechanical properties such as tensile strength and modulus[1-4], and electrical properties such as resistivity[2, 5, 6] for fiber materials.
(COV~5%) SDM High Affected little by the angle to electron beam.
(COV<1.6%) ADM Low Affected substantially by the angle to electron beam.
[15] "ASTM D4018 - 11 Standard Test Methods for Properties of Continuous Filament Carbon and Graphite Fiber Tows", 2011