Search results

Mechanical vibration cutting devices have the advantages of simple structure, low cost, convenient for operation and maintenance and its vibration parameters are little affected by load.
Scholars in Japan and the former Soviet Union believed that cutting force was centralized in a very small range of partial blade, the range of cutting force on workpiece material was very small, the transferring of energy was concentrated, the original lattice structure of material changed little, then the metallographic structures and physical properties which were similar with base metal could be got
CHEN Jie et al [9]from Chinese Academy of Engineering Physics, during the experiments of low-frequency vibration turning of tungsten-based alloy materials, regarding the machining accuracy of turning as the research subject, using orthogonal method, selecting three influential factors(feed rate, cutting speed, vibration amplitude), did full-factor orthogonal tests based on three factors and three levels.
(2) Contrast experiments Contrast experiments refer to set two or more groups of experiments, by analyzing the results comparatively, to explore the relationship between some factors and the research subjects.
[14] CHEN Guang-jun, GU Li-zhi: Mechanical Engineer Vol.10 (2005), p. 25-27.

Several factors that influence the corrosion rate in acid include pH, temperature, solution concentration, and the presence of oxidizing ions [5].
It demonstrates an increase in immersion for each specimen, influenced by the occurrence of microgalvanic corrosion due to the previously corroded ground specimen, which provides a potential difference capable of affecting the corrosion properties of the polished specimen.
Danaee, "The effect of repeated repair welding on mechanical and corrosion properties of stainless steel 316L," Mater.
Khorshahian, "Microstructure and mechanical properties of resistance upset butt welded 304 austenitic stainless steel joints," Mater.
Mahmoodian, "Effect of Applied Stress on Corrosion and Mechanical Properties of Mild Steel," J.

This method makes use of the QR decomposition linear algebra techniques and so on, and it updates the matrix square-root of the state covariance by the Cholesky factor updating.
The upper triangular part of, , is the transpose of the Cholesky factor of, i.e., ,such that.We use the shorthand notation qr{•} donate a QR decomposition of a matrix where only «± is returned[3].
Cholesky factor updating.
If S is the original Cholesky factor of , then the Cholesky factor of the is denoted as .
Conclusions In this paper the SR-CDKF control algorithm was introduced into the sensorless vector control of ship propulsion motor control system due to the CDKF algorithm is the optimal estimation method and the model of the propulsion motor in the process of actual operation can't be identical with the actual system, adopting PI speed controller system unavoidably affected by parameters change, but the SR-CDKF has better numerical properties and guarantees positive semi-definiteness of the underlying state covariance, it is not sensitive to external disturbance and parameter variation, it has very strong robustness.

Introduction Ti-6.0Al-2.0Zr-1.0Mo-1.0V alloy is a near α titanium alloy used in aviation and aerospace industries because of an attractive combination of mechanical properties such as the high specific strength, excellent fracture toughness and good heat/corrosion resistance.
The equivalent stress in three tracked points increases with the increasing of shear factor
Table 1 shows the effects of punch velocity and shear factor on the temperature rise.
Therefore, the punch velocity and friction affect the deformation load significantly.
Peng: International Journal of Mechanical Science Vol. 44 (2002), p. 2415-2425.

The principle of ground well arrangement Because of the existence of various factors, the ground CBM development has been overshadowed.
Of course, there need certain surface and geologic condition for ground well, so the topographic and geologic factors must be considered.
Discussion The above only discussed the basic principle and key factors for surface CBM well net design, but its feasibility need to be proved by field practice.
Study on Control Factors of Rock Mechanics Properties of Coal-Bearing Formation.
Research on Mechanical Property Test and Mechanism of Hydraulic Fracture of Gas Well in Coalbed.

Comparing the consequences, the sliding planes and safety factors agreed well with the result of limit equilibrium method.
The internal stress and physical and chemical properties has changed greatly.
Table 1 Rock mechanical parameters E(mpa) v (Kpa) 2800 0.2 10 30 Fig.2 The Finite Element Computing Model Fig.3 shows the sliding plane when the water depth is 30m.
And the safety factors (showed in Table 2) coincide well.
It is showed in Table 3, that the safety factors of the two conditions are very close.

Introduction Mechanical properties of dense polycrystalline ceramic materials for environmental application (such as membranes and filters) are poorly known.
In fact, those materials are always manufactured as porous and sometimes cannot exist in dense state without microcracks in a wide range of temperatures, because of their large thermal expansion and mechanical properties anisotropy.
Conversely, if the properties of the porous material are available (i.e., p, eMacro , sMacro and are measured) the dense material properties and pore morphology (m) can be evaluated.
The input material properties are given in Table 1 (taken from literature [11]).
Input properties for the FEM calculations d Element size [mm] 3.36, 4.48 Ed Element Young's Modulus [GPa] 350 nd Element Poisson ratio 0.15 g Surface crack energy density [J/m2] 0.30, 0.45, 0.60 The finite element model of the pore structure consisted of cubic volume pixels (voxels) of the same size and with isotropic mechanical properties (Fig. 2a).

Recent research results showed that the addition of non-metallic second phase particles such as oxides, borides and carbides could remarkably improve mechanical properties and wear resistance of metal matrix composites[1-5].
The addition of rare-earth (RE) in metal materials has multi-functions, such as purification, modification and alloying, thus can improve a series of properties of metal materials.
Bouchoucha et al. [8] indicated that the friction coefficient was essentially affected by the mechanical properties of the formed oxide films on the sliding surfaces.
The wear of Cu- La2O3 composites was determined by mechanical wear.
The wear of the composites was mainly affected by mechanical wear when the electrical current is low.

The smoothness of surface finish is one of the properties that determine the performance of a stent.
Annealing is the key technology that affects the material’s final crystal grain size.
Gachon et al.[2]examined the influence of laser cutting accuracy on the mechanical properties of stents.
Becher, Laser cutting: influence on morphological and physicochemical properties of polyhydroxybutyrate, Biomaterials. 22 (2001) 2447–2452
McHugh, Accuracy of laser cutting and its influence on mechanical behavior of stents, Proceedings of SPIE. 4876 (2003) 574-581

Introduction Concrete cracks are caused by many factors, and the mutual influences are complex[1].
Concrete thermal stress test can simulate and control the concrete specimens in different temperature histories and different constraint degrees[6], it is possible to test the characteristics and parameters of the concrete from the curing begins (such as zero- stress temperature, the cracking temperature, stress, volume deformation, coefficient of linear expansion, etc.), it can quantitatively evaluate the cracking sensitivity of the concrete with comprehensive factors in early age.
As we know, the concrete cracking is affected by its temperature history when it is restrained.
So the development of the concrete mechanical properties such as strength, elastic modulus will be faster than general in approximate adiabatic heating mode, which overestimated the highest temperature and the cooling point of the concrete and underestimated the actual cracking resistance.
Because the chemical deformation and the creep of concrete is complicated within the different temperature processes which is not a linear relationship, the generation of stress are related to the deformation, temperature, modulus of elasticity and other mechanical properties.