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Thermal-mechanical coupling stress field is mainly analyzed as the following three steps.
(a)Thermal analysis is conducted; the temperature field of structure is obtained; (b) the analysis unit in the model is changed into the corresponding structure analysis unit, and thermo analysis obtained first is imposed on the nodes as the body load; (c) the options needed in the other structural analysis are defined, and the structural analysis is conducted. 4.1 Steady-state thermal analysis 4.1.1 Boundary conditions of temperature As Engine cylinder head works under the complex conditions such as high temperature and pressure, actual thermal boundary conditions are affected by a lot of internal and external factors, resulting in the larger difficulty to calculate accurately actual thermal boundary conditions.
The thermal properties of materials are defined; the heat transfer coefficient of materials can be defined in the material model window according to the above thermal boundary conditions.
And other properties will be defined during the structural stress analysis.
The mechanical property and thermal expansion coefficient as well as the elastic modulus and Poisson's ratio for materials are defined in accordance with the definition of material properties for the mechanical stress under preload conditions.

The experimental configuration of this study was planned using Taguchi orthogonal array, where the drill diameter, rotation speed, power and feed rate were taken as the experimental factors.
The effect of control factors on the holes quality was discussed from the straightness deviation and maximum material removal rate of related factors on the holes when the Taguchi method was used in rotary ultrasonic machining of holes drilling.
Experimental results showed that cutting force direction might affect holes deviation on inclined plane of work pieces.
The experiment was done in three steps: first, four experimental parameters are chosen based on MRR affecting cutting operation, as shown in Table 1; second, three level values are given to each experimental parameter, and 9 groups of tests are carried out according to Orthogonal Array (OA) of L9 (32) chosen; third, mean value of Taguchi Method is used for analysis, and the characteristics of surface roughness of target function are converted into Signal Noise Ratio (S/N).
The contribution on MRR of every factor shows as in Table 3.

For this reason the problem of accelerating manufacture the ceramic molds with advanced physical and mechanical properties is important.
The process is cycled, unlike usual methods it provides the higher degree of GM cladding evenness at smaller CA consumption due to the following factors: – the extend of the working face CA with the GM particles as a result of its feeding in the form of spray; – the absence of "crushing" loads between GM particles in the liquid state, which lead to delamination of the CA film; – every CA spray worked-out GM particle's committing oscillatory and rotating modes, providing even bleeding CA over all the GM particle surface.
Besides, developed technology contributes to improving the physical and mechanical properties of ceramic molds.
Herewith, there were estimated physical and mechanical properties of the given molds, and there was also studied the kinetics of the ceramic coating layers freezing.
In Table 2 there can be seen the studying results of physical and mechanical properties of ceramic samples, and in Figure 3 there is represented the micro structure of the molds with the use of clad stucco.

The existing models should be perfected by the three aspects of enlarging the sample size, selecting main factors, F-test and t-test.
Dependence of biodiesel fuel properties on the structure of fatty acid alkyl esters[J].
Impact of fatty acid methyl ester upon cold flow properties for biodiesel[J].
Impact of composition and molecular structure upon the cold flow properties for biodiesel[J].
Blending effects of biodiesels on oxidation stability and low temperature flow properties[J].

These alloys are thermo-mechanically processed, and their formability and mechanical properties is dependent on a number of factors.
Alloys with small amounts of Mn have been found to give variations in properties such as extrudability and mechanical properties[7].
This would affect the precipitation behaviour of the ageing elements, which could influence the final ageing.
It is uncertain how the presence of Cu may affect the precipitation behaviour.
[3] O Reiso, U Tundal and J Andersen, The effect on cooling rate after homogenization and billet preheating practice on extrudability and section properties. part2: Microstructural investigation, Metall and Mat Trans A, 1 (1995) 141-147

Second, the deposition temperature caused the changes of the deposition type such as debris, whiskers and films and these changes of morphology affect the various properties.
Silicon carbide whiskers have been widely researched since they are effective materials for the reinforcement of various composite materials with their outstanding mechanical and chemical properties [3,4].
Among these properties, the most important factor is the minimizing pressure drop since it is directly related to decreasing the energy efficiency of combustion engines.
It means that the deposition morphology affects not only the mechanical strength but also gas permeability.
After CVI process onto the porous Al2O3 substrate, the mechanical property was improved.

Addition of different types of calcined bauxites to the ceramic plate formulation was performed to study effects on the firing and properties of the resulting ceramic plates.
The degree of secondary mullitization was the main factor affecting the performance of the ceramic plate.
Zanelli, et al, Processing and properties of large-sized ceramic slabs, Boletín De La Sociedad Española De Cerámica Y Vidrio, 4 (49) (2010) 289-295
Bó, et al, Effect of reduction of thickness on microstructure and properties of porcelain stoneware tiles, Ceramics International, 9 (40) (2014) 14693-14699
Romero, Effect of microstructure on mechanical properties of porcelain stoneware, Journal of the European Ceramic Society, 30 (15) (2010) 3063-3069.

Piston ring-cylinder liner is an important influence factor of the engine ideal combustion.
Their tribological properties exhibit a direct impact on environmental protection and energy saving of the entire engine.
Besides, the strengthening effect of nanocrystalline and multilayer composite structure caused a substantial increase of wear resistant and lubricating properties of Cr / CrN coatings.
The presences of these large droplets not only affect the surface morphology, but also reduce other properties of the films, such as corrosion resistance and mechanical properties.
Hu, Effect of nitrogen ratio on phase structure and tribological properties of CrNx coating, Transactions of materials and heat treatment. 28(2007) 134-137,144

Special attention should be paid to the strength against crack initiation at a free-edge (i.e. intersection point of the interface and a free-surface) as a severe stress concentration occurs depending on the edge shape and the elastic properties of the materials [1].
Recent advancements in micro-mechanical tools that can be combined with various microscopes (SEM, TEM, AFM) have enabled one to implement quantitatively reliable minute experiments [2-4].
The effect of free-edge shape on the properties of crack initiation strength is then carefully compared with the previous results [5].
In a Type B specimen, the near-edge sy shows rectilinear distribution represented approximately by sij = Kij/rl, where l is the singularity index and Kij the stress intensity factor.
On the other hand, the crack initiation in Type A specimens is affected by factors other than the free-edge.

Hydrogen in many metallic materials, such as carbon steel [1-5], stainless steel [6-9], and aluminum alloys [10-12], affects their mechanical properties negatively.
However, the reported hydrogen permeation reduction factors vary significantly.
Hirth, Effects of Hydrogen on the Properties of Iron and Steel, Metall.
Nakai, SCC properties of 7050 series aluminum alloys in T6 and RRA tempers, J.
Shibata, Evaluation of Mechanical Properties of Metals at 45 MPa Hydrogen, J.