Take One Step From The Yingjiang Containing Scandium Rare Earth Ore System Aluminum-magnesium Scandium Master Alloy

This article introduces basic characteristic of metal scandium as well as the way to produce scandium. Additionally, this article presents the outstanding property of aluminium scandium alloy, introduces the recent research of aluminium scandium alloy in the world wide, and analyzes the main problems which impact the large-scale application of aluminium scandium alloy. This article argues that scandium oxide can be extracted through rare earth, chloride scandium oxide to produce non-water chloridized scandium fulgurates; by using aluminium magnesium heat deoxidize technology. We created a new technology to produce aluminium magnesium scandium alloy. In order to correct the warp of scandium alloy, we simulate and calculate magnetic field and whirling field of the electric-magnetic agitation crystallization machine, By using this technology, scandium can be used effectively, manufacturing of scandium alloy can be shortened, the cost can be deoxidized, therefore, large-scale application of scandium can be promoted. The main research can be concluded in the followings:(1) Put forward a brief introduction of rare earth resource, scandium manufacture and current situation of aluminium scandium alloy. Presents the difficulty of aluminium scandium alloy manufacture, presents a new technology and process which extract aluminium scandium alloy from rare earth directly, refined scandium could be lixiviated out by hydrochloric acid, furthermore, use highly purified chloride scandium solution to produce non-water chloride scandium fulgurate, then use aluminium magnesium heat method to deoxidize aluminium scandium interalloy.(2) Calculate Jibuse free energy change in the process of aluminium deoxidize to chloride scandium, Jibuse free energy change in the process of magnesium deoxidize to choride scandium, and Jibuse free energy change in the process of magnesium aluminium deoxidize to chloride scandium. These three kinds of reaction under the condition of purified substances indicate that: under 1200K, 1Pa, aluminium cannot deoxidize chloride scandium to scandium, while, magnesium can be used to deoxidize chloride scandium to scandium, the standard balance constant K is not big, aluminium magnesium can deoxidize chloride scandium to scandium very easily, and the standard balance constant K is quite big. This demonstrates feasibility of using aluminium magnesium deoxidize scandium is more available. Similarly, in the process of reaction, both of aluminium and magnesium take part in reaction, magnesium is the main effect, and aluminium is the auxiliary, Al₃SC was produced in this process.(3) Based on properties of rare earth, use select ore method of mineral selection to extract scandium oxide from rare earth, figure out the process of manufacturing of basic selection of scandium and refined selection of scandium. In the process research, we use 120,000V super high voltage suspending electric selective machine to do this experiment, which is a patent of our research group. After research, we discover the optimal condition to manufacture aluminium magnesium scandium alloy from rare earth, which is the base of manufacture aluminium scandium interalloy.(4) Use OA theory to research scandium's physical properties, scandium is a kind of very active metal, could react with acid easily, metal shine can be lost in air quickly, but the erosion of water is slow, can be oxide by air under high temperature. Researching from the process of extract and separation, analyze the main factors which impact rare earth extract balance, modelling rare earth extract balance distribution. By using this method, analyze four mechanisms of scandium extract from rare earth: scandium's neutral phosphorous extract, acid phosphorus extract, anime extract and integrated extraction, put forward the method and difficulty of using balance calculation model to extract and to separation.(5) On the basis of research of manufacture aluminium magnesium scandium interalloy by rare earth, experiment research of scandium extract has been done. In the aspect of rare earth lixiviate scandium, we research lixiviate density, lixiviate liquid to solid rate, lixiviate temperature, lixiviate time, lixiviate granule rate and lixiviate solution. In the aspect of extract scandium from rare earth, we research extract acid degree, extract time, extract rate and anti-extract vibration time, and get our optimal result.(6) Scandium's effect in alloy indicated that Sc's strengthened effect is far more effective than other rare earth metals. Sc whose atom diameter is the least among rare earth metal incurs the least distortion, the highest solution rate, the difference between purified aluminium melting point and Al-Sc duality temperature is also the least one, these properties made Sc to be saturated by solid solution easily, and produce Al₃SC in the process of heat and extrusion. Al₃Sc can nail crystal border and keep in small gain, improve alloy's intensity, restrain re-crystallization, improves alloy's heat stability.(7) According to the research above, we conduct the process experiment of aluminium magnesium scandium interalloy production through rare earth, in which we adopt the new process of restraining the generating of ScOCl and dehydration for crystal water rare earth chloride: Inert gas temperature increases rapidly to a certain centidegree to dehydrate ammonium chloride and crystal water. We did the experimental research for the temperature of crystal water, amount of ammonium chloride, time, temperature growth speed, influence of inert gas flow toward to scandium percent hydrolysis, whereby, we conclude the optimal process condition in this period: Temperature: 400°C, proportion of oxidized scandium and ammonium chloride is 1:1.5(Proportion of oxidized scandium and additional salt is 1:5.4), time is 120minute, temperature growth speed is 10℃.min^-1 inert gas flow is 5L.min^-1.(8) As far as scandium aliquation concern, we put forward the method of electric-magnetic stirring to correct scandium aliquation. On the basis of ANSYS software, we did the simulative calculation of electric-magnetic stirring magnetic field. We formulate the calculation procedure and steps, discussed the difficulty in modelling, and adopt the method of magnetic field/flow field coupling to get the following result: by the drive of electromagnetic force, the liquid in crystallizer rotates. The rotation speed and liquid rotation area is associated with the magnitude of electromagnetic force. The magnitude of magnetic field is high within the central cross section of electric-magnetic stirring equipment, therefore, the flowing area of rotation is big, and moreover, the flowing speed in central area of broadside is higher than narrow side and corner. Consequently, rotative magnetic field drive the rotative flowing of liquid, which bring a strong scour against the solidifying front of broadside, heat exchange is fast, the development of columnar crystal is restricted, electric-magnetic stirring improve the intermediate alloy aliquation in a good extent.