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Introduction Sintering is one of the significant links in preparation process of ceramic tool material, since it determines the microstructure and further the final mechanical property of ceramic tool material.
However, affecting mechanism of sintering process on the microstructure is still not clear, it is difficult to accurately control grain growth and microstructure of nanocomposite ceramic tool material through experiments.
However, these models do not take into account sintering parameters that affect grain growth.
Sintering pressure is an important parameter affecting grain growth of ceramic tool material, research indicates that there exists a direct relationship between grain growth and sintering pressure [5,6].
(8) The highest sintering pressure is given 32MPa according to the properties of nanocomposite ceramic powders and hot-pressing sintering experimental equipment.

The lower bond strength obtained from these adhesives can be attributed to several factors.
Nanoindentation has enabled investigation of mechanical properties on a very small scale.
Other mechanical properties can also be determined from this experiment.
For the phosphoric acid-etching system both dentin and enamel suffer loss of mechanical properties due to aggressive etching.
For the self-etching MDP-containing system, the interface is rather thin with minimal loss of mechanical properties.

The room temperature and 600°C tensile properties were tested on ENST-1196 test machine, and the properties data were the mean value of two tested samples.
So the forging temperature and heat treatment are the central factors which affect the volume fraction of primary α phase.
Tensile Properties.
The samples isothermally forged at different temperature have different tensile properties, as shown in Fig. 5.
Fig. 5 Tensile properties of TG6 isothermal forgings: (a) at RT, (b) at 600℃ The majority of phases in TG6 alloy are α phase after the heat treatment (1015°C, 2h, AC + 700°C, 2h, AC) because of the low content of the β stabilisers, so the tensile properties are affected mainly by the morphology and distribution of α phase.

Diamond-like carbon (DLC) films have attracted great interest due to their outstanding mechanical, biocompatibility, thermal, optical and electrical properties.
The nanoindentation is an excellent method for measuring nanomechanical properties of both bulk and thin films.
Such excellent properties of DLC films suggest many practical applications immediately [5].
The levels for four factors are listed in Table 1.
Xi and Xj are the process parameters or factors.

Clearly, the electrical properties of the epilayer and, consequently, of the Schottky barrier formed on it, can be strongly influenced by the presence of these defects.
Moreover, also the quality of the metal-semiconductor interface influences the carrier transport properties [4,10].
The obtained ideality factors were about 2.
As seen, the small dimension of the C-AFM tip increases the series resistance (affecting the forward saturation current) but does not affect the linear part of the ln(I) vs.
When the area is reduced by a factor of 900 (radius reduced from 150 µm to 5 µm), a dramatic improvement is observed in the electrical properties of the diodes.

Preparation of Fe-Cu-Based Friction Material and its Adoption in Automobile Mechanical Mechanism Hao Li*, Bo He Guang'an Vocational and Technical College, Guang'an, Sichuan, China *Corresponding author e-mail: 529674144@qq.com Keywords: Fe-Cu-based friction material; automobile mechanical mechanism; carbon fiber; friction and wear.
Based on the above factors, in this study, the advantages of Fe-based and Cu-based friction materials are combined to prepare Fe-Cu-based friction materials that are of high temperature resistance for automotive machinery.
It owns the advantages of high temperature resistance of Fe-based friction materials, and also of good thermal conductivity and friction coefficient, which means it can be widely used in mechanical mechanisms.
Table 2 Properties of Fe-Cu-based friction materials with different carbon fiber content Carbon fiber content (%) 0 2 4 6 8 Actual density (g/cm3) 5.04 5.41 5.01 4.87 4.62 Theoretical density (g/cm3) 6.24 5.85 5.63 5.35 5.04 Density (%) 85.3 93.3 89.7 86.1 80.76 Porosity (%) 17.2 7.1 10.0 13.4 14.2 Hardness (HV) 83.4 118.1 120.2 89.7 103.2 The shear strength and impact strength of friction-based materials added with concentrations of 0%, 2%, 4%, 6%, and 8% carbon fiber are tested respectively.
Only the carbon fiber factors that affect the friction and wear resistance of Fe-Cu-based friction materials are studied.

., Prosecka 76, 190 00 Prague, Czech Republic avlastimil.kralik@fsv.cvut.cz, bjiri.nemecek@fsv.cvut.cz, ckoudelkap@itam.cas.cz Keywords: aluminium foam, spherical nanoindentation, micromechanical properties, plastic properties Abstract.
The aim of this paper is to identify, in addition to elastic properties, inelastic properties of tiny aluminium foam cell walls that can be directly deduced from the load–depth curves of spherical indentation tests using formulations of the representative strain and stress.
Some deviations received from different tests arose and, therefore, their effect on the evaluation of inelastic properties is discussed.
The parameter C is referred to as "constraint factor".
The correct determination of material properties by spherical indenter depends on the exact knowledge of its radius.

Introduction Laser cladding is a rapid solidification process, by using high-energy density laser beam and rapid melting the different materials on the substrate surface, forming the metallurgical bond layer with completely different composition and properties.
There are cracks and other defects on the cladding layer which using a single ceramic powder, while a single Ni-based powder coatings has been difficult to achieve high wear resistance, high hardness and other properties.
The quality of laser cladding layer depends largely on the cladding layer microstructure and mechanical properties, so it is particularly important to explore the influence of the laser process parameters (laser power, scanning speed, etc.) microstructure and micro-hardness of layers, and then control them [3].
Powder Preparation: 5% ZrO2 and 95% Ni60A powder were mechanical mixed, and baking.
Conditions and Factors for Obtaining Optimum Coatings in the Laser Coating Process by a Powder Feeding Method.

The size effect peculiarities in NMs are analyzed and the complex influence of grain size and other factors on NM properties is emphasized.
Table 3 shows the electrical properties of oxides with different grain sizes [18-20].
Table 3 Electrical properties of microcrystalline and nanostructured oxides.
It is evident that thermal activation and other factors such as radiation, deformation and chemical reactions lead to the enhancement of diffusion, relaxation and recrystallization with particular or total annihilation of nanostructure, nonequilibrium phases, different defects and residual stresses that are responsible for the NM properties.
Therefore, an understanding of the factors that affect NM stability and degradation is critical to identify the best strategies for future technology development.

Introduction Duplex stainless steel during manufacturing process may cause the precipitation of some harmful second phases, for instance, the σ phase, which seriously deteriorates the mechanical properties, increases the opportunity of stress corrosion and limits the applications of DSS [1-7].
Because the precipitation of σ phase can significantly affect the mechanical properties and corrosion resistance of duplex stainless steel, it is necessary to clarify the precipitation mechanism and influencing factors of σ phase during solidification.
Zhang, Influence of σ phases on the microstructure and properties of S32760 super duplex stainless steel, Chin.
Liang, Microstructural evolution, precipitation and mechanical properties of hot rolled 27Cr-4Mo-2Ni ferritic steel during 800 ℃aging, Mater.
Zhou, Precipitation behavior of sigma phase and its influence on mechanical properties of a Ni-Fe based alloy, J.