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Selective Transfer Phenomenon in Copper-Steel Tribological Systems Andrzej Kotnarowski1, a 1 Department of Mechanical Engineering, Radom Technical University al.
In this layer, the elastic-plastic deformations generated during friction process act under the principle of a diffusion-vacancy mechanism, don not affecting deeper zones of cooperating elements surface layers.
To identify real factors influencing µ (p) characteristics subsequent investigations should be carried out concerning mainly surface layer composition.
Marczak: Garkunov effect in mechanical engineering.
Kotnarowski: Influence of differences in copper chemical content o its tribological properties.

Frictional Characteristics of Tool and Material in Turning Particulate Reinforced Iron-based Composites Lifa HAN 1,a, Shengguan QU 2,b, Shouyan ZHONG1,c , Chunxiao XIE1,d 1 College of Mechanical Engineering, Dongguan University of Technology, Dongguan, China 2 College of Mechanical Engineering, South China University of Technology, Guangzhou, China a tonyhan98@21cn.com , b Qusg@scut.edu.cn, cszhongy@263.net, dchun-xiao@163.com Keywords: Friction, Iron-based composites, Turning, Coated carbide tool Abstract.
Although iron-based composites have many excellent properties, the machining of such materials faces serious challenges[7-9].
Due to the influence of reinforcing particulates, pores and oxide impurities in matrix, serious tool wear will happen in short period of time, which causes adverse affect on machining quality.
As the frictional status between tool and workpiece materials strongly affects the tool wear, sequentially affects the machining accuracy and surface integrity, therefore, the frictional characteristics of cutting tool and workpiece should be paid great attention in machining iron-based composites.
Among these two contributing factors, the scraping of hard particulates on the tool is dominant, thus, the average tool-chip friction coefficient (µav) increases with the increase in NbC mass fraction.

IPNs have been extensively studied because of their simplicity in combining the properties of a wide range of materials, ranging from plastics and elastomers to hydrogels and the formation of IPNs tends to enhance the desirable properties of each constituent polymer, resulting in what is commonly known as positive synergism effects
But the PNIPPAm hydrogel have poor mechanical properties which limits its application, while polyurethane(PU) exhibits high tensile strength and breaking elongation which can supplement hydrogel's shortcomings.
[12] Therefore, with the BIS amount increasing, the ESW of composite films formed in water increases, and the properties of PNIPAAm are the leading factor in film structure.
Summary PNIPPAm formed semi-interpenetrating polymer networks with polyurethane, and the interactions between polymer chains and solvent molecules are the leading factor in determining the properties of film.
The content of crosslinker and the solvents' properties dominate the composite film's nature.

名词 1. mechanical 2. machinery 3. machine 4. mechanism 2.
The wall of the package becomes thicker and thicker so that volumetric efficiency and productivity are reduced, significant energy is wasted, and also the quality of aluminum is affected.
Considering various factors comprehensively bigger cutter plate diameter is 630mm and number of teeth z1 is 36.
A clear analysis of structure and properties of machine tools [J].
Mechanical engineer, 2008.12 [2] Ke Tao, Shiquan Yu.

CNC Cutting Performance in Processing Using Cool-air Cutting Technology Jing He 1, a, Guangsheng REN2,b 1 Department of Electrical and Mechanical Engineering Chongqing Engineering Polytechnic College, Chongqing 400037, China 2 The State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, China ahjlth@163.com, brgs_tiger@163.com, Keywords: Traditional cutting; Dry cutting; Oil solution cutting; Cool-air cutting technology; Life expectancy of cutter; environmental pollution.
Steel 45, alloy 2WCrNi and titanium alloy are analyzed under different cooling conditions; cutting life and processing quality are evaluated and contrasted to find out the phenomenons which affect the cutting life.
Alloy of titanium (Ti-6AL-4V) has good mechanical properties and excellent high-temperature deformation ability.
Tool wear will be significantly reduced when cool-air cutting technology is used in processing. 2) The attrition value of Flank under different cutting environments almost equal in initial wear stage (VB within 0.11mm).As the factors which influence the state of tool wear in initial wear stage is the form of the tool itself, the contact surface between Flank and finished surface is small (almost a line) and with high stress, so the tool wear rate is higher in primary stage.
Research on BT20 Titanium cutting force under low temperature [J]. mechanical engineer,2006.9

During actual calculations, perforators could only contribute gravity load, therefore such presumption would not affect strength analysis of perforating gun.
Because dynamic load was not taken into account in the calculation, the hypothesis would not affect the strength calculation of the structure.
It also has good wear resistance, high tensile strength and the excellent relaxation properties.
After decreasing thickness, buckling factor decreased, but still was stable.
Sheng: Detail of CATIA Mechanical Design command(Machinery Industry Press, Beijing, China, 2009)

Rossello [4][5] and Ashraf Ragab [6] Mohamed’s researches indicated that the property of ITZ between aggregates and mortar in concrete would affect the crack’s extension route.
If the interface has exorbitant adhesive strength and excessive interface mechanical properties (strength, elastic modulus and fracture energy), the “trans-aggregate” cracks will exist; otherwise, the “along aggregate” cracks will exist.
At present, plenty of researches have been carried out on the interface and the concrete’s properties with the quantitative relationship between the interface phase properties and the concrete’s toughness indefinite nevertheless.
What kind of properties that the interface phase material shall feature to have the optimal toughness?
The 2D concrete model with random distributive aggregate is adopted to calculate the mechanical property of concrete with flexible interface phase material.

The joint characterization program consisted in the assessment of welded joints creep properties.
Mechanical and creep properties of weldments were measured both in the as welded and post weld heat treated conditions and proper WPS's were designed in a manner such that industrial production needs were satisfied.
Accordingly, welding techniques are highly needed for joining these materials with comparable high temperature properties [2].
Mechanical properties of both grades fulfil the ASTM requirements, Table 2.
The welded joints creep strength, of utmost importance for materials used in high temperature applications, must be assessed in order to obtain safety factors for the design and to ensure safe working conditions of the components.

Use elastic theory method[6] to analyze the factors affecting pile settlement, we can obtain the following conclusions: not only do the lower pile modulus mixing pile exhibit the characteristics of flexible piles, but also the higher pile modulus ordinary pile will show the characteristics of flexible piles with the increasing pile length; the division of flexible and rigid piles depends on the aspect ratio of the pile and pile stiffness(the ratio about elastic modulus of pile and elastic modulus of the soil ).
When the loads on the piles reach their ultimate bearing capacity and the settlement of pile top reaches its allowed top settlement amount, the soil layers around piles are always in the elastic-plastic phase, therefore, we must establish the calculation models which can reasonably describe the load transfer characteristics of the super-long pile, and can also consider the pile top load, pile top settlement, mechanical properties of soil, the material of pile, the geometrical dimension of pile, and pile formation technology etc, in order to reasonably determine the effective length of single pile through the control method of the ultimate bearing capacity and the control method of settlement of pile top.
Relationship curve of effective pile length and the control factors Calculation method of the load-settlement curve.
(3)Determining effective pile length is a very complex problem, it is related to many factors.
(4)Due to the influence factors of effective pile length is very complex, there are still big differences in determining the effective pile length between the static load test, model test, field monitoring and numerical analysis method at present.

SMPU properties can be customized depending on a variety of factors, including molecular weight and type of soft segment, symmetry and type of hard segment, and chain extender which will essentially affect the morphology-property relationships.
PU produced using symmetric diisocyanates and urea as hard segments showed superior microphase separation, crystallinity, good mechanical behaviour and elastomeric properties as compared to unsymmetrical MPDI, TDI and HMDI.
The thermal properties of the PU samples were investigated using DSC analysis.
Shape memory properties of the synthesized PU is summarized in Table 4.
Ding, Largely improved mechanical properties of a biodegradable polyurethane elastomer via polylactide stereocomplexation, Polymer 137 (2018) 1-12