Experimental Study On Optimal Preparation Of Fe-Cu Prealloyed Powder

With the development of hydrogen metallurgy technology driven by the green economy,powder metallurgy technology has gradually developed in a green and low-carbon direction.The application of hydrogen energy in the field of powder metallurgy has also received extensive attention.In the field of powder metallurgy,there are many preparation methods for pre-alloyed powder,which are mainly divided into three categories:mechanical alloying method,atomization method and hydrometallurgical method.This article combines the above preparations,the process characteristics of the method and the development and optimization of the preparation process of the pre-alloyed powder according to the deficiencies of various methods.The Fe-Cu pre-alloyed powder with small particle size and uniform morphology was prepared by mechanochemical method,and the process was efficient.No pollution,simple production equipment,short preparation cycle,low production cost,suitable for large-scale production.In this paper,the Fe-Cu pre-alloyed powder is prepared by a pre-alloyed powder preparation process combining mechanical ball milling and hydrogen reduction.First,the basic process route is summarized,During the period,the thermodynamic calculations were performed on the reduction of Fe₂O₃ and Cu O by hydrogen,and the feasibility analysis of the experiment was carried out,and then use mechanical ball milling to pre-alloy the mixed oxide.By comparing the particle size and morphology of the obtained powder,the optimal ball milling time is selected,and the precursor is prepared by granulation And analyze the influence of mixed oxide pre-alloying on the reduction process,and then prepare Fe-Cu pre-alloyed powder by hydrogen direct reduction method,by adjusting the reduction temperature and time and other parameters,discuss the above factors on the reduction rate,The influence of the particle size,morphology and phase composition of the pre-alloyed powder,and the selection of the best preparation process parameters,and finally on the basis of the process,La is added to the precursor powder to prepare La-containing Fe-Cu pre-alloyed powder,and The effect of adding La in the process of preparing pre-alloyed powder on the reduction temperature and time,as well as the optimization of powder morphology,particle size and phase composition are analyzed experimentally.The particle size of the powder can be effectively refined by mechanical ball milling.After 3 hours of ball milling,the particle size of the mixed oxide powder is fine,the morphology is uniform,and the dispersibility is good.It is suitable as a precursor powder for reduction;and the mixed oxide powder can be Produce oxide composite phase,realize the pre-alloying of mixed oxide powder,and the pre-alloying effect can realize the simultaneous reduction of hydrogen of each oxide while reducing the reduction temperature;during the hydrogen reduction process,the reduction temperature is under the same time condition The higher is,the higher the reduction rate is.Under the same temperature condition,the longer the reduction time is,the higher the reduction rate of precursor powder is.In the case of ensuring complete powder reduction,the higher the temperature,the larger the powder particle size during the reduction time.The Fe-Cu pre-alloyed powder prepared at 750?,40 min,and hydrogen flow rate of 1 L/min has an average particle size of 0.68?m,uniform size and approximately spherical shape,and the alloy phase is in the form of intermetallic compound Fe Cu₄ exist.In addition,the addition of element La can optimize the preparation of Fe-Cu pre-alloyed powder,reduce the required reduction temperature,and refine the particle size of Fe-Cu pre-alloyed powder.The element La content is 0.1wt%,the hydrogen flow rate is 1 L/min,and the reduction temperature The average particle size of Fe-Cu pre-alloyed powder prepared at 700?and holding for 40 min is 0.4?m,uniform particle size distribution,good dispersibility,approximately spherical shape and high surface finish,and element distribution is in a uniform solid solution state.