| As a rare metal,silver is favored by human because of its good financial and metallic properties.At present,silver has gradually evolved from the original jewelry product industry to the industrial direction due to its good wire properties and thermal conductivity.With the development of electronics industry and aviation industry,silver has been widely used in many kinds of fields,such as electrical,electronic,pharmaceutical,chemical,disinfection,antibacterial,photosensitive materials and so on.Anaerobic silver is the metal material with the best conductivity,excellent ductility and excellent thermal conductivity among all metals which has been known at present.However,silver will incorporate a large amount of oxygen during the "solid-liquid" phase transition,and the oxygen that is incorporated will quickly precipitate in large quantities when it cools and solidifies during the "liquid-solid" phase.On the one hand,the "splash" phenomenon of oxygen during precipitation will bring about gaps and pores on the inner and outer surfaces of silver.On the other hand,a portion of oxygen that is not completely precipitated will residue in the solid silver lattice which greatly reduced the integrated performance of silver.Currently,the high temperature casting process of silver is mainly carried out in the air.It greatly increases the difficulty of obtaining anaerobic silver.At the same time,the use of manual pouring not only wastes a lot of labors,but also threatens the personal safety of the operators.In order to obtain high-purity anaerobic silver which contains excellent wire properties,thermal conductivity and ductility relatively.The lattice structure and vibration law of silver in solid state and the dynamic behavior of oxygen assimilate into and separate out of silver has been researched in this paper by mainly focused on the theory of thermodynamics,lattice dynamics and lattice vibration.At the same time,the mechanism why nitrogen does not blend into silver has been explained,too.The integration mechanism of oxygen assimilate into silver and the results of its existence form in the silver have been derived when silver is converted between "solid-liquid" and "liquid-solid".Which are when the temperature is less than 800?,the residualoxygen that has not been completely released in the last round remains in the solid silver with the form of a meta atom;When the temperature is greater than 800?and less than 961.63?,very few of oxygen atoms will blend into the surface of the silver lattice;when the temperature is greater than 961.63?,the oxygen atoms will be deeply incorporated into the liquid silver in a very short time.Based on the above theory,this paper developed a metal automatic pouring machine specially for metal such as silver which named oxygen-containing automatic pouring machine.And explaining its general working principle and working process.The biggest feature of the pouring machine is the ability to isolate oxygen which ensure the metals are protected away from oxygen during "solid-liquid" and "liquid-solid" phase transitions.In addition,The pouring machine can greatly improve the pouring efficiency and pouring precision by the ability of automatically control the pouring process.The motion model of the pouring machine during the pouring process and the working torque of the drive input shaft are obtained with theoretical analysis of kinematics and dynamics.Apart from this,This paper combines the actual situation with kinematics and finite element simulation analysis of the pouring machine based on the above theoretical analysis.The parameters such as the trajectory,speed and so on in each moving part are obtained by kinematics simulation through ADAMS to simulate its motion state during work.Finally,the feasibility of the oxygen-containing automatic pouring machine was verified by ANSYS which can carry out the finite element simulation analysis of dynamics and temperature field of some components during operation. |
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