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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)

Water Content Test As a solvent and media,water is the raw material of crop photosynthesis,and also an important factor for keeping metabolism and constituting the plant’s body.When water is shortage,the crops will reduce productions,even die[2].The water mainly coming from the moisture of soil is absorbed by crops’ roots,so the water content in the soil can directly affect the growth and yield of crops[3].Our team tested the water content in the fresh samples by the way called drying and weighing.The results are shown by Form 3-1.
WC(%) A1 14.59 C1 11.82 A2 22.81 C2 21.41 A3 46.40 C3 43.49 B1 11.34 D1 13.41 B2 22.21 D2 22.81 B3 42.51 D3 47.68 PH Value Wheat is the main crops in China.Its yield and quality is affected by their own characteristics,but the main factor is the environment of growth,including soil conditions,climate factors, geographic location,etc.The PH value can largely affect the fertility factors , physical and chemical properties in soil[4].The best PH value for wheat growing is 6.5.When the PH value is higher than 7 or lower than 6,the activity of amylase, protease and lipase are reduced during the wheat seeding;the rate of breathing and endosperm decomposing become slowly;germination is slow;the seeding grow slowly caused by low activity of roots and nitrate reductase,chlorophyll content,rate of photosynthesis
The form 3-3 shows that the water suction in Class A is a little higher than Class C,but it is lower than Class B and D.However, the thickness of covered soil in Class C is approximately two times of Class A which cause the cost of reclamation much more higher,and the water content in Class C is lower than Class A on the natural condition.So according to all the above factors,Class A is the best
Conclusion The on-site investigations and researches of reclaimed land in Shangyao town show that:①The layer of fly ash has good properties of water-resisting, water-saving, water-holding and water-supplying for covered soil;②There are different properties of water-saving,water-holding and water-supplying between different levels of covered soil.Under the lowest condition of soil the wheat needs, considering the costs of reclamation and efficiencies of yield at the same time,the best thickness of covered soil in reclaimed land of Shangyao is between 24cm and 40cm.
[6] Fink P K.Lusth J C.Expert system and diagnostic expertise in the mechanical and electrical domains[J].IEEE Trans SMC,1987,17(3):340-349

Friction stirring typically induces microstructural changes and grain refinement, affecting the processed material's constitutive response.
In terms of mechanical properties, FSW can result in desirable microstructures as it can produce refined equiaxed recrystallized grains, and it allows for controlling the residual stresses during the welding process [4], [7].
However, the effect of friction stir on materials' high-strain-rate properties remains insufficiently characterized or understood, though it might be significant.
Several factors may contribute to this observation.
Miller, “Effect of friction stir welding on dynamic properties of AA2024-T3 and AA7075-T7351,” Welding Research Supplement, vol. 80, pp. 196–200, 2001

Accord to the production technology of metal mines, this paper analyses the reason of environmental pollution, concludes the existent pollution factors and their harmfulness and finally discussed technology measures of treating and controlling for environmental pollution in production process of metal mine.
Introduction Because of excellent mechanical properties, processing properties and low cost, metal materials become the largest used and most widely applied materials in the present mechanical industry.
Because different minerals have their own physical properties, chemical properties and so on, they also have different beneficiation methods.
The Control of Pollution Factors There are different levels and types of pollution in various stages of metal mines production process.
It will affect direct or indirect environment pollution by means of dust flying or poisonous gas diffusing and rain erosion. ④.

It was found that the mechanical properties of microhardness values are between 151.70 to 155.80 HV and the tensile strength values are between 472.71 to 491.12 MPa according to transverse and longitudinal sections of the specimens.
Cost reduction and versatility are the main driving factors in both production and product design.
Mechanical properties of the deposited material were quantitatively tested by microhardness inspection, centered around the centerline of the wall.
It will induce the downflow of liquid metal, and the surface quality of the component will be atrocious, affecting the quality of the part.
Feng: Effect of location on microstructure and mechanical properties of additive layer manufactured Inconel 625 using gas tungsten arc welding.

Moreover, most of ER fluid properties are changed under condition of temperature variation [4,5].
In the case of long-time use of ER device, the performance of ER device can be affected by the temperature of ER fluid which is caused by mechanical friction.
Four kinds of ER fluids are prepared with different optimized compositions and important properties of ER fluids are measured and compared.
These values are determined by not only static factors such as particle concentration but also dynamic factors such as operating temperature.
In this work, the properties of ER fluid operated under the shear mode are investigated.

The components of self-lubricating composite coating can be easily designed, could behavior self-lubricating and wear-resistance special properties on the basis of excellent mechanical property of the matrix materials, and greatly save raw materials and production time by the usage of coats lubricate.
Although the generation and properties of solid self-lubricating film have drawn great attention from material sector and tribology sector, and have make much research on it.
This essay discusses the self-lubricating effect and action mechanism of MoS2 film in the Ni60A/MoS2 composite coating by means of researching the tribological properties of the Ni60A /MoS2 composite coating.
When MoS2 in the coating rub with other materials, it could form a layer of solid lubricate film between two surfaces, which affects lubricating and elevating anti-friction properties.
It is because of MoS2 in the friction course to the counterparts, could generate a layer of solid lubricate film, which plays a role in lubrication and improves its wear resistance properties.

Identifying the influencing factors, however, was known to be difficult due to the complex interaction between yarns, in which multiple factors were often studied in a coupled manner and cannot be isolated.
Comparison between energy absorption capacity and mechanical properties of different woven fabrics, damage mechanisms, and influencing factors remains an area yet to be explored.
Material models of aramid yarns (Kevlar® 29) were constructed using mechanical properties obtained through experiments.
Transversely isotropic elastic mechanical properties were used to simulate the anisotropic response of the yarns.
The mechanical properties of yarn include a density of 1230 kg/m3 and a failure strain at 3.5%.

Introduction In addition to the physical properties of rock and the exposed area of surrounding rock, the main factors affecting the radon exhalation rate in tunnel include the weather conditions and ventilation styles.
Fig. 5 Relationship between natural ventilation quantity and radon exhalation rate 2) Correlation analysis of radon exhalation rate and temperature (1) Regression equation Based on the mechanism of radon exhalation, the key factor affecting the radon exhalation rate is the pressure difference between the inside and outside of the tunnel and the pressure difference is due to the temperature change.
A vortex will be formed when the air flows through the air door [9], seriously affecting the uniformity of radon distribution in tunnel.
Determination of radon reduction rate and exploration on its influence factors[J].
Estimating large-scale fractured rock properties from radon data collected in a ventilated tunnel[A].

The study from [2] stated that sawdust briquettes as fuel have physical and mechanical properties as well as thermal.
Table 3 summarizes the interactions between the response variables and the predictive factors.
Research on the relationship between factors in the volatile matter is in line with research by [11] which explains that the decomposition of biomass structure significantly affects temperature.
Carbonization could improve the physical properties of teak sawdust.
Bakhri, The Effect of Particle Size, Pressure, Holding Time and Drying Temperature to the Physical and Mechanical Properties of Briquettes, Mater.