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The advantages of squeeze casting include elimination of gas and shrinkage porosity, reduction of metal wastage and improvement of mechanical properties.
The results indicate that the properties of the SiCp/Al composites depends on the particle volume fraction and are greatly improved by hot extrusion, while, the extrusion ratio does not affect the properties of the extruded composites.
Because of the addition of the aluminum powder in the preform, some Al2O3 phases were introduced in the SiCp/Al composite, which affects the properties of the composite.
The mechanical behavior of a composite is affected by the presence of reinforcement particles dispersed in matrix material.
The yield strength of the matrix in the extruded composite may, in fact, be higher than that in the as-cast composite because of factors such as increased dislocation density and reduced grain size.

All in all, the research on rock Rheological properties has a very important and practical significance on engineering, and it’s one of the hot and difficult problems in rock mechanics research.
In addition to the rock samples in strictly accordance with the International Society of Rock Mechanics (ISRM) test procedures to process, in order to prevent the moisture affects the rheological mechanical properties test results the processed rock samples should maintain the original and natural moisture content, and the test state is natural state.
The formulated and improved BP neural network can analyze the rock rheological constitutive model[7-8].朗显示对应的拉丁字符的拼音 The stage loading method was used in rock rheological mechanical properties test, which means that after applying a certain stress level, then observe the rheological deformation.
It can be seen from the figure that the network predicted values are very close to the experimental values when considering temperature influence, so it can reflect the nonlinear properties under stage loading very well.
The Improved BP neural network model through appropriate self-learning that can automatically grasp the complex rheological mechanical properties of rock and can reasonably reflect the nonlinear relationship of the rheological parameters, which provide another way to analyze and solve the long-term stability and security of rock engineering.

It has been established that all of the mechanical and physical properties characteristic for nodular cast iron are the result of the graphite being substantially or entirely in the spheroidal/nodular shape such that its bulk physico-mechanical properties are determined primarily by the steel-like matrix [1].
The resulting properties of the cast iron are affected depending on the matrix type.
Characterisation of the Graphite Phase To correlate the graphite phase with the mechanical properties of cast iron, the graphite particles are characterized according to the shape by several different parameters.
Angus, Cast Iron: Physical and Engineering Properties.
Vaško, Analysis of the factors influencing microstructure and mechanical properties of austempered ductile iron, Communications, Vol. 11, 2009, No. 4, p. 43-47

It is clearly noticed how the modified epoxy maintains the mechanical properties even at temperatures higher than 200 °C.
In addition to the enhancement of mechanical properties (strength), the carbon nanotubes show low electrical resistivity and good thermal conductivity.
In the case of glass reinforced epoxy pipe, it is known that the epoxy resin can absorb water that will affect the resin's mechanical and creep behaviour.
This will reduce the loss in mechanical properties.
Using nanoreinforcements will be possible to improve the fire resistance behaviour without affecting their mechanical properties and avoiding the use of hazardous materials.

Finite element analysis for performance of cap seal rings in the Stirling engine piston rod Chang Jun1, a 1School of Mechanical Engineering, Lanzhou University of Technology, Lanzhou city, Gansu province, China achangjun0931@163.com Keywords: Rod seal; cap seal structure; stress analysis; Finite Element Analysis.
Abstract: Cap sealing reciprocating seals are dry friction conditions, the paper separately from the main factor moving the cap seal sealing mechanism, wear mechanism, elastic modulus theoretical analysis of its sealing properties and tribological law.
Introduction Stirling engine as key components of plate type heat generators system, its performance directly affects the working efficiency of plate type heat power generation system.
Because the cap seal is under the condition of dry friction of reciprocating dynamic seal, so the factors for influence effects of cap seal is complex.
Summary This paper, using the finite element software ANSYS to analysis the cap sealing in the “installation” state and mechanical properties under medium pressure at working, studied the cap type sealing ring contact stress and the Von Mises stress regularities of distribution with the change of sealing medium pressure, It is possible tear failure location for sealing rings, O shaped rubber ring contact began form center, and along the top of the piston rod contact position, this conclusion in order to further improve the sealing performance of Stirling engine piston rod sealing device and, provides a way to predict sealing rings of tearing failure location.

For the situation that concrete engineering required rapid and timely repair after nature disaster, setting time and influencing factors of phosphate rapid repair material were studied in this paper.
Phosphate cement with an early rapid hardening, low-temperature hydration properties, volume stability, corrosion resistance[2,4], was suitable for the rapid prepair of concrete engineering after disaster.
Meanwhile, in order to improve the mechanical, microstructure properties and color of phosphate cement it often need to adjust the water-cement ratio, the ratio of phosphate and dead-burned magnesium.
Therefore, the effect of these factors on setting time of phosphate cement should be studied and it can provide the theory support for the rapid prepair of concrete engineering.
With the continuous growth of hydrate nucleation, grow up and even with each other and make contact with magnesium phosphate cement to form a dead body burned MgO particles as a framework, phosphate binder crystalline hydrate crystal structure for the network, so that hardening magnesium phosphate cement paste with high mechanical properties for the hardened body [2].

Secondly, the analysis of mechanical properties of AZ31 magnesium alloy sheets at high temperature The relation between the temperature and tensile strength, the yield strength and elongation of AZ31 magnesium alloy sheets after fracture are shown as Fig.3.
The deforming temperature is one of the main factors of plastic deformation capacity.
The properties of various phases are different when AZ31 magnesium alloy is deformed.
The depth of the dimples is mainly affected by the deforming capability.
On the other hand, the grains grow abnormally, prone to oxidation corrosion, and the mechanical properties and surface quality decline when drawing at the temperature more than 400˚C.

Constitutive modeling [3-5] is an effective method to evaluate mechanical characteristic of a material.
The frequently cited constitutive model, which has taken the factors of environmental temperature and density into account, is developed Sherwood and Frost.
Materials and methods The new cushioning material uses polyether polyol and polyisocyanate as matrix and corn straw fiber as reinforcing factor.
Therefore, the proposed static model and dynamic model are able to characterize the cushioning properties of the experiment material, and to offer theoretical guidance to further research.
Wang: Study on the corn stover fiber cushioning package materials and its dynamic properties [D].

Currently for the restoration of worn functional surfaces or the production of surfaces with properties exceeding the properties of base material often the processes of arc welding are used.
In the paper there is a choice of particular components presented, surfaces of which are worn by the combination of various tribodegradation factors in the operation.
As the abrasive medium aluminum oxide was used (Fig.6), the physical properties of which are shown in Tab. 7.
Conclusions The paper presented options of the components renovation, surfaces of which are exposed in the operation to extreme tribodegradation factors.
From these factors the most common are abrasive-adhesive wear combined with impacts, high surface pressures as well as corrosion.

Research reveals that the formation of slivers is closely related to the processes of steel making and rolling as well as conditions of equipment in operation, and, in most cases, due to different factors affecting together.
Therefore, during steel making and rolling, it is an important target to achieve good surface quality while maintaining good chemical composition, metallographic structure and mechanical property of the strip.
Discussion Analysis of cause of the defect As previously described, sliver defects on the surface of cold rolled strip present in different features, and the affecting factors and forming mechanism are very complicated.
It’s clear that the causes of defects are very complicated, the affecting factors involving steel making, continuous casting and rolling, as well as status of equipment in operation.
It’s necessary to have a comprehensive analysis on various affecting factors as regards all the related procedures in the whole steel making and rolling process before conclusion could be made.