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Has high temperature resistance corrosion, wear-resistant properties.
A single factor method was adopt to study the temperature of 4Cr9Si2 steel during cross-wedge rolling, which namely change one factor and fix other factors respectively.
As the same time, the microstructures also will uneven due to temperature difference and thus affect the mechanical properties.
So, in order to control defeats and improve mechanical properties of product in CWR technique, it is necessary to control the rolled piece temperature difference.
So higher die temperature will greatly increase the rolled piece temperature uniformity, thereby reducing the product defects and improving the mechanical properties.

To show the effects of the materials gradients on the crackopening-displacements (CODs) and the stress intensity factors (SIFs), numerical results for a pennyshaped crack are presented and discussed.
Introduction Functionally graded materials (FGMs) are advanced composite materials with continuously nonhomogeneous material properties.
Numerical results for a penny-shaped crack are presented and discussed to show the effects of the material gradation on the crack-opening-displacements (COD) and the stress intensity factors (SIFs).
Normalized stress intensity factors versus the polar angle Summary Elastostatic crack analysis in 3D, isotropic, functionally graded and linear elastic solids is presented in this paper.
Numerical results for a penny-shaped crack are presented and discussed to explore the effects of the material gradation on the crack-opening-displacements and the stress intensity factors.

In addition to the influence of mechanical stresses during the service, corrosive environment affects metal structures, machine parts, which leads to the process of gradual accumulation of damage.
Metal fatigue is the process of gradual accumulation of damage under the influence of variable stresses (deformations), leading to a change in properties, formation of cracks and destruction [1-5, 15].
Metals and alloys are divided by changing the physical and mechanical properties during fatigue into: cyclically hardened, cyclically softened and cyclically stable.
, V (CRE) Coefficient a, [V] N0, [cycle] φ0 Value 0.05 -6.9 0.4 [V] Standard error 0.01 3.10 0.02 p – single normalizing factor Fig. 4.
Zakirova, Change in mechanical properties of two-layer steel 16GS + 08Kh13 in the process of long-term operation, Metal Science and Heat Treatment, 51 (9-10) (2009), 450-453.

Hence, methods are needed to assess the fatigue resistance of prospective of new materials based on a substantially reduced test matrix of mechanical properties.
It should be noted that this value is still well within the range of small scale yielding for the given mechanical properties.
Because there is no mismatch in elastic properties, the elastic fracture mechanics relations for the mixed-mode stress intensity factors, energy release rate and phase angle are all unchanged.
Hence, in the context of small-scale yielding, mismatches in plastic properties affect only the elastic-plastic behavior in and around the crack tip plastic zone, which in turn affects the plastic dissipation per cycle.
Indeed, applications in welding, soldering and layered manufacturing result in a heat affected zone, where a grading of mechanical properties can exist between layers.

Steel suitable for the responsible elements in general machine construction, especially designed for heat treated parts, which are used for maximum mechanical properties of the steel.
Graphs of the chosen roughness parameters after burnishing and after turning treatment on the conventional lathe (a), CNC lathe (b) and after grinding (c) In the burnishing process there are many factors affecting the quality of finish surface, e.g. the material from which the workpiece is made, the way of the burnishing, number of passes of burnishing tool, loading forces of the tool to the surface, the operation preceding burnishing process and the quality of execution of burnishing tool.
The value of the asperities height and its arrangement may affect on the tribological properties of parts.
For the steel with the pearlite-ferrite structure one can observe zone with strongly deformed, fragmented and oriented grains, creating texture, exhibiting altered mechanical properties.
Patyk, Problems Determining of the Mechanical Properties of Metallic Materials from the Tensile Test in the Aspect of Numerical Calculations of the Technological Processes, Applied Mechanics and Materials 474 (2014) 454-459

Because of their poor machinability, it is very difficult to machine Ti-6Al-4V alloy with traditional mechanical cutting [1].
Fonda et al. used EDM technology to machine Ti-6Al-4V alloy to examine the effect of thermal and electrical properties on the productivity[1].
The essential steps include identifying the factors that are to be included in the study and determining the factor levels.
Table 5 and Table 6 show that the Voltage is most significant process parameters affecting the multiple machining responses.
The voltage affecting Material removal rate and Electrode wear ratio with nearly 58% of contribution ratio and the duty factor has almost a 21% contribution.

Many external and internal factors affect the dynamics of the conduct, change and transformation of each of these processes, both individually and jointly [4, 5].
Experience has shown that such an approach does not always allow an adequate assessment of the factors under study.
Thus, the issue of studying the dynamics, physical, mechanical and chemical properties of the process of strength gain of an artificial stone based on a cement binder is still a topical issue, despite the large number of works and studies of domestic and foreign scientists.
Yerofeyev, Regression dependency of basic properties of cementstone with change of its structure and age.
Lukina, The possibility of affecting the activity of the surface of cement minerals, Cement. 6 (1992) 75-78

Introduction Epoxy resin (EP) has the excellent characteristics of chemical resistance, toughness, low shrinkage on cure, and mechanical resistances properties [1].
Polyamide-imide (PAI), which is a kind of thermoplastic resin，has good heat resistance，dielectric property，mechanical property and chemical stability[2]．Recently, one approach involves the preparation of PAI-EP composite resin, which exhibits good wear-resistance and heat-resistance [3].
Because different heating rate of resin system affect the maximum temperature of DSC curve obviously, the method of non-isothermal temperature curing DSC is often used in thermal analysis [4,5].
Fig.1 shows that the unique exothermic peak controlled the whole curing course of Polyamide-imide-epoxy resin system, and different heating rate can affect the shape of curve, curing temperature, and the heat of cure reaction of resin system.
The frequency factor A was connected to the molecular collisions will increase when reaction temperature rise.

Stress intensity factor.
The approach is presented through stages: detection of defects, stress-strain analysis of loaded component, characterization of material properties required for structural integrity assessment and application of convenient procedure.
As an example, in Fig. 2 is presented fracture of thick wall pressure vessel, experienced in 1964, caused by (1) presence of an undetected crack in welded joint and (2) poor fracture toughness properties in critical region, caused by improper heat treatment, which could not be determined that time [4], but post-festum.
analyzed numerically exploiting the property of J integral path independence [19].
Testing of experimental specimen of welded joint, shown in Fig. 8, with combined weld metal (OM-overmatched, UMundermatched WM), followed by clearly recognized different microstructures in the heat-affectedzone (HAZ) regions and ended by parent metals (BM) on both sides, revealed significant differences in crack resistance properties: high in BM, with expressed scattering in HAZ depending on region properties and crack tip position, and low, confirming crack behavior in Figs. 6 and 7.

Then the micro structure and mechanical properties of specimens sintered with the best optimal parameters have been analyzed.
After the orthogonal experiment analysis, one parameter combination was chosen to fabricate specimens with aim to further analyze the micro structure and mechanical properties.
Mechanical properties test process For further examination of the mechanical properties of sintered specimens, the experiment specimens were designed as dimension 100×10×6 mm3 in shape of dumbbell for tensile experiment, and size in 40×6×6 mm3 specimens for flexuralexperiment.
Conversely, the porosity is increase with the increase of other factors.
Mechanical properties of sintered PC specimens Except possess some medical properties, the medical parts must maintain sufficient mechanical properties for use requirement.