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Finite element simulation for laser deposition process of graphite copper gradient composite of thermal stress Longzhi Zhao*1,a,Pengwei Chen1,b,Deying Li1,c, Mingjuan Zhao1,d,Jian Zhang1,e 1Key Laboratory of Ministry of Education for Conveyance and Equipment, East China Jiaotong University, Nanchang 330013, China azhaolongzhi@163.com,bcpw501@163.com,clideyingecjtu@163.com, dzhaomingjuan100@163.com,ezhangj@ecjtu.edu.cn * Corresponding Author: Professor Longzhi Zhao; Email: zhaolongzhi@163.com Key words: laser direct deposition,Gradient composites,Element birth and death technology, Thermal Stress Field Abstract.Taking account of the special structure of gradient material and take advantage of good toughness properties of copper,Based on Ansys secondary development technology, using the Gauss moving heat source and the element birth and death technology, a laser direct deposition of graphite copper gradient composite thermal coupling model was developed;On the basis of accurate
For the solid-phase area using thermal elastic and plastic theory,Isotropic hardening Mises yield criterion and Prandtl-Reuss flow incremental theory,plastic incremental theory to deal with the relationship between stress and strain,and using ideal elastic-plastic model as a mechanical model of transient thermal stress[7].
In order to obtain the ideal process parameters and simulation models,and can further simulate by process parameters of the laser, as well as the factors affecting the convective heat transfer,which thus provides theoretical guidance for laser deposition FGM.
References [1] Likai Shi,Shiyou Gao,Mingzhe Xi: Acta metallurgica sinica Vol. 42(2006),p.456 [2] Risheng Long,Weijun Liu,Hongyou Bian,Fei Xing:Chinese journal of mechanical engineering Vol. 43(2007),p.77 [3] Wenpeng Jia,Xin Lin,Jing Chen:Chinese J.Lasers Vol. 34(2007),p.1310 [4] Zhenxia Liu,Jing Chen,Weidong Huang,Dingyi Wu: Chinese J.
Lasers Vol. 36(2009),p.3227 [6] Qingfang Ma,Rongsheng Fang,Licheng Xiang,Shun Guo:Practical manual for thermophysical properties (China Machine Press Publications ,Beijing 1986) [7] Yao Fu:Numerical simulation of temperature field and stress field of laser powder deposition (Beijing Jiaotong University Publications, Beijing 2007)

Following conventional batch annealing, strip samples exhibit properties approaching those of commercial wrought sheet of an equivalent grade.
Assuming equivalent if not superior properties and performance, then the single most important factor to achieve this will be simply driven by economics.
This can be inferred from reference to mechanical properties such as ductility, tensile stress and elongation to failure for CP Grades 1 to 4 [2].
Comparison of PM derived sheet properties with wrought material.
[2] Boyer, R., Welsch, G. and Collings, E.W. (1998) Materials Properties Handbook: Titanium Alloys, ASM International

Their small sizes, high surface-to-volume ratio, high thermal properties, high energy density and catalyst role are one of the unique properties that enhance the system performance [2].
In this approach, power, duration, and dispersion volume are the major factors that influence breaking the agglomerates [7].
This condition resulted in a lower aspect ratio, causing the deterioration of the material’s tensile properties [19].
Graphene Platelets and Their Polymer Composites: Fabrication, Structure, Properties, and Applications.
An overview on the effect of ultrasonication duration on different properties of nanofluids.

As the bones used in this study were taken from different bodies, the cutting force values are closely dependent on the mechanical properties of bones.
As the bone density is one factor affecting the drilling force most, so in the next stage, we will measure the bone density so as to do more analysis on the drilling force.
(3) For the great differences of mechanical properties among the bones, cutting forces of each bone were also different from each other.
In order to discover the influence factors to the cutting forces, other factors related to the mechanical properties should be concerned such as bone density.
Krause: Mechanical effects of orthogonal bone cutting, Ph.D.

Craciunescu1b 1 "Politehnica" University of Timisoara, P-ta Victoriei nr. 2, 300007 Timisoara, Romania a email:ion.mitelea@mec.upt.ro, b email:craciunescucm@yahoo.com Keywords: friction welding, dissimilar materials, carburized steels, microstructure, properties Abstract Friction welding is one of the most reliable joining techniques for various materials due to a high reproducibility, lack of ecological treats and a relatively narrow thermomecanical affected zone.
Friction welding of dissimilar materials is a known procedure, but still subject of research activities in order to optimize the resulting properties [1-3].
The processing history of the parts on the friction welding is also considered in order to estimate the resulting properties [6].
The properties of the surface layer are known to be influenced by the carburization conditions such as the carbon potential, the temperature and the duration of the process as well as by the hardness gradient over the thickness.
Conclusions The main factor that is influencing the expulsion of the rich carbon layer from the joint plane of two carburized low alloyed steels is the friction path.

Applying modification on PVDF membrane can improve its hydrophilicity and anti-fouling properties, of which blending modification is expected to be a hotspot of study in future.
Solvent type, coagulation bath medium, temperature, and additives are all important factors that have influences on PVDF membranes.
The composition and the temperature of coagulation bath will influence the exchange rate between solvent and non-solvent, thus affecting membrane structure and performance.
The retention rate of bovine serum protein increased from 25.11% to 67.20% and mechanical properties are certainly improved.
Conclusions During the process of preparing PVDF by means of immersion precipitation, solvent, coagulation bath and additives are vital factors of influencing the structure and performance of membrane.

In recent years, people pay more attention to study the relationship between the structure and properties of SGF-TPU composites.
The structure of SGF-TPU composites for example, fiber orientation, distribution and fiber length, has great effect on the properties of SGF-TPU composites [5].
So it is meaningful to further study the properties of SGF-TPU composites academically and experimentally.
The tensile properties were obtained from INSTRON 1185.
Kutty, Mechanical Properties of Short Polyethylene Terephthalate Fiber Thermoplastic Polyurethane Composite, Int.

The analysis of variance (ANOVA) was adapted to identify the most influential factors on the CNC end milling process.
The cutting speed is found to be the most significant factor affecting the surface roughness of work piece and tool wear in end milling process.
These superior properties plays an important role in the modern manufacturing industries, especially in aerospace ,automobiles, electronics and cutting tool industries.
Methods and Materials Surface roughness is one of the important factors to measure the quality of machine components.
Literature shows that [17-19] machining parameters like feed rate, cutting speed and axial depth of cut is the most dominant factors.

But the electrical resistivity of RB-SiC had not affected by the oxidation at 900�.
The oxidation mechanism of RB-SiC and the affecting factor on oxidation of RB-SiC were analyzed and discussed.
Though the effect of high temperature oxidation on silicon carbide mechanical properties has been understood long before and studied [1-3], the studies on the oxidation of reaction-bonded silicon carbide (RB-SiC) are reported seldom.
It can be seen that the oxidation of RB-SiC didn't affect its electrical resistivity and the RB-SiC with large particles sizes still held lower electrical resistivity.
The microstructures of RB-SiC were sounder and the oxidation of RB-SiC took place on it surface, so that the oxidation of RB-SiC could not affect its electrical resistivity.

This form of piezoelectric films present unique challenges in determining its properties.
In the event that the specimen survive the preload, friction force between the force probe and the specimen may cause it to penetrate the top electrode hence affecting the accuracy of measured piezoelectric charge coefficient [13,14].
Influence of Piezoelectric Film Geometry and Material Properties on d33.
Effect of Substrate Material Properties on d33.
To assess the influence of substrate material properties on determined d33 coefficient and calibration factor, the substrate material (brass) was replaced with aluminium and silicon (see Table 3 for material properties details).