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Wear of metal surfaces is a complex phenomenon due to various causes and determined by a large number of factors and conditions.
Concomitant intervention of the composition or nature of materials in contact, mechanical properties, quality of surfaces resulting from the execution technology, functional parameters (load, speed, temperature), quality of lubrication and lubricant (where applicable) and many other disruptors factors cause the wear of metal surfaces to occur as a consequence of different causes / phenomena, whose action overlaps.
The same ductile behaviour can also be observed in heat affected zones, for both materials and also for the weld.
In the case of the weld, heat affected zones and the hub, almost identical measured values can be observed, which confirms the welding technology chosen for the two different types of materials.
In view of the results obtained, in particular for the base material of the axle, and the way in which it broke during operation, we can draw the following logical conclusions: The rupture of the axle in the original state could have occurred due to: - fatigue of the material over time, in the area with maximum stress, because of exceeding the service life; - improper use - operating shocks + excessive fatigue due to certain factors: wear of sliding bearings, improper mounting (misalignment of axles), wear of drive elements.

Because of the complexity of hemming process, diversification of design parameters of automotive panels hemming die, and the nonlinear of material mechanical property, it is not a easy work to predict and control the defects of hemmed panel, so in the actual manufacturing process, skilled workers have to tryout the hemming die again and again to minimize the quality defect of automotive panels.
Further in their paper studied how edge line radius, hem length and final hem force to affect forming defects during the flat surface-convex edge hemming process by the way of orthogonal matrix method [3].
In this paper, based on the finite element simulation, a mechanical model of hemming process was constructed.
Geometric and process parameters are: inner panel and outer panel thickness t = 0.9mm, punch radius Rd = 1mm, flanging die corner radius Rp = 2mm, flange length L=6mm, distance between inner panel and flanging die 2mm, gap C = 0.99mm, pre-hemmer angle = 45°, friction factor 0.1.
Mechanical model of hemming process Considering the complexity of hemming process, the finite element analysis combined with mechanical model method was proposed to analyze the bending moment and warp in the hemming forming process.

For manufacturing of micro holes Electrical Discharge Machining (EDM) can be used, which is well-established due to its thermal working principle that allows almost force free machining independent of the material’s mechanical properties.
Experiments by Kunieda et al. [1] described basic properties of the dry EDM process.
DoE is used for the optimization of processes by acquisition of control, interference and properties data [5].
The overview contains the percentage change of targets goals caused by an increase of the factors from the lower to the upper level.
The high stability of the discharges during dry EDM is a consequence of the properties of the dielectric fluid used in the process.

The major factors affecting wood density are growth rate, tree age and heredity [2-4].
The density of wood has an important effect on the physical, mechanical and chemical properties.
The relationship between wood density and fibre properties is important for the conversion of wood anatomy into wood quality.
Variation of microfibril angle and its correlation to wood properties in poplars.

The basic formula of the grouting material leads to different and different mechanical properties.
The setting time improves durability and other properties.
The retarder uses sodium citrate, sodium tetraborate, disodium hydrogen phosphate, tartaric acid, etc., a kind of concrete setting adjuster, which delays the initial and final setting time of concrete without affecting the later strength of concrete.
Experimental study on the influence of various mineral admixtures on the mechanical properties of super high-strength concrete[J].
The influence of several admixture components on the properties of sulphoaluminate cement [J].

., Xuzhou 221400; 3China University of Mining and Technology, Xuzhou 221000) a89202974@qq.com Keywords: welding, numerical analysis, storage tank, stress Abstract: Welding is the main means of the connection of tank, is also an important factor in determining tank quality.
Welding stress and deformation under certain conditions may affect the function and appearance of weldments, and therefore are the issue that must consider in designing and manufacturing . 2.
Therefore, It is appropriate selection of model of welding heat source or not will affect the simulation accuracy of welding temperature field and deformation greatly, especially near welding heat source.
(1)Definition of elements and materials (2)Definition of unit Type: Select Brick 8node 45 Unit. 4.3.2 Definition of material properties: the elastic modulus EX = 2e5, Poisson's ratio PRXY = 0.3. 4.4 Create a model of the cylinder and pipe Ammonia storage tank is bilateral symmetry and sagittal symmetry, because only consider the stress of internal pressure, we can take advantage of the symmetry of the structure to model for 1/4 of the region of opening .
Chinese Journal of Mechanical Engineering, 2005, 41(9): 228-231.

Introduction Obtaining a good compromise of mechanical properties, namely sufficient ductility while preserving tensile strength, creep and oxidation resistance, is one of the main challenges for manufacturing TiAl intermetallics components by the casting route [1].
As the mechanical properties of γ-TiAl are very sensitive to the microstructure [2], TiAl alloys are often heat treated [3,4,5].
This factor represents the height over length ratio of the ledges.
The lamellar spacing is also affected by the nominal composition of the alloy.
More specifically it has been shown recently that excellent mechanical properties of cast γ-TiAl can be obtained by tempering massively transformed samples in the (α+γ) region [14].

Whereas, when damage is activated, Figure 2(a) clearly shows that one cannot easily predict the ultimate strength and ductility using the local plasticity-damage model as both properties are mesh-dependent.
Khaleel, "Influence of martensite mechanical properties on failure mode and ductility of dual-phase steels," Metallurgical and Materials Transactions, vol. 40A, pp. 796-810, 2009
Khaleel, "On key factors influencing ductile fractures of dual phase (DP) steels," Materials Science and Engineering A, vol. 526, pp. 140–149, 2009
Priestner, "Influence of ferrite-martensite microstructural morphology on tensile properties of dual-phase steel," Journal of Materials Science, vol. 31, pp. 2091-2095, 1996/01/01 1996
Tekeli, "The effect of martensite volume fraction and particle size on the tensile properties of a surface-carburized AISI 8620 steel with a dual-phase core microstructure," Materials Characterization, vol. 49, pp. 445– 454, 2003.

Introduction Titanium alloys, possessing the high strength-to-weight ratio due to the low density, the ability to retain high strength at high temperature up to 500oC, high heat resistance due to low thermal conductivity and high corrosion resistance, have wide applications in aerospace industry because of these unique properties.
Volume fraction of primary alpha phase is also an important factor to determine the machinability of a titanium alloy because of its correlation with the strength [3].
The volume fraction and morphology of these phases which depend on the heat treatment temperature determine the deformation behavior and mechanical properties of this alloy under both quasi-static and dynamic loading conditions [4-7].
The contribution of each factor changes with increase in cutting speed.
Summary (1) Microstructure of Ti-6Al-4V alloy affects the cutting force and chip formation only at cutting speed lower than 100m/min.

These resin materials have favorable handling properties, and can be easily attached to the original tooth.
Previously, it was reported that the thickness of the HAp layer was one of the most important factors to produce well-crystallized coatings on titanium substrates under hydrothermal conditions [15].
Spector, Compressive properties of cancellous bone defects in a rabbit model treated with particles of natural bone mineral and synthetic hydroxyapatite, Biomaterials. 22 (2001) 1953–1959
Ebihara, Effects of substrate temperature on the properties of Ga-doped ZnO by pulsed laser deposition, Thin Solid Films. 513 (2006) 90–94
Xiao, Effects of substrate temperature on the properties of CdTe thin films deposited by pulsed laser deposition, Surface and Coatings Technology. 213 (2012) 84–89.