Refining and purification is a significant way to obtain pure and high-quality magnesium alloy melts.This paper summarizes the flux refining methods and non-flux purification methods(blowing purification,filtration pu...Refining and purification is a significant way to obtain pure and high-quality magnesium alloy melts.This paper summarizes the flux refining methods and non-flux purification methods(blowing purification,filtration purification,electromagnetic purification and ultrasonic purification).It also introduces the composite refining technologies that have been widely researched and applied in recent years,including low-voltage pulse electromagnetic technology,ultrasonic argon purification,self-purification technology and non-flux continuous purification technology.Among them,the non-flux continuous purification technology integrates a variety of purification methods,which can produce high-quality magnesium alloy continuously and steadily,realize environmental protection production,and achieve remarkable technical and economic benefits.展开更多
The effects of non-flux purification techniques on the mechanical properties and microstructure of AZ91 magnesium alloy were investigated by ICP,OM,XRD and SEM.The results show that Ar spraying with high flow rate cou...The effects of non-flux purification techniques on the mechanical properties and microstructure of AZ91 magnesium alloy were investigated by ICP,OM,XRD and SEM.The results show that Ar spraying with high flow rate could remove non-metallic inclusions and improve the mechanical properties of AZ91.The alloy obtains the best properties after argon spraying for 30 min at the melt temperature of 740 °C.The ceramic foam filter(CFF) could effectively improve the ultimate tensile strength and elongation of AZ91 alloy,especially the elongation,which increase with increasing pores per inch(ppi) and the thickness of CFF.Non-flux purification does not change the microstructure of AZ91 alloy.However,filtration has a certain effect on the fracture pattern of AZ91 alloy.To improve the mechanical properties effectively,both filtration and gas spraying should be utilized together.展开更多
A new flux which can remove both Fe and non-metallic inclusions in magnesium alloy was introduced. The Fe content of the magnesium alloy can be decreased greatly from 0.062% to lower than 0.005% (degree of AZ91D) af...A new flux which can remove both Fe and non-metallic inclusions in magnesium alloy was introduced. The Fe content of the magnesium alloy can be decreased greatly from 0.062% to lower than 0.005% (degree of AZ91D) after being purified by this new flux. The optimum addition of B2O3 in the flux is 0.58 % by Gaussian Curve Fitting. Corrosion rate was measured after the specimen being immersed in 5% NaCl solution for 3 d. The results show that the corrosion rate of the magnesium alloy after purification by the new flux is only 0.3 mg·cm-2·d-1. On the other hand, non-metallic inclusions in the magnesium alloy decrease with increasing addition of JDMJ in the new flux. Average volume fraction of the non-metallic inclusions in the magnesium alloy decreases from 1.52% to 1.08%, which leads to improvement in the mechanical properties of the magnesium alloy by 30%. The mechanisms of Fe reduction and non-metallic inclusion-removing in magnesium melt by purification with the new flux were also revealed.展开更多
基金The authors gratefully acknowledge the financial support provided by 2018 Dongguan Key Technology Key Projects(2019622134013)。
文摘Refining and purification is a significant way to obtain pure and high-quality magnesium alloy melts.This paper summarizes the flux refining methods and non-flux purification methods(blowing purification,filtration purification,electromagnetic purification and ultrasonic purification).It also introduces the composite refining technologies that have been widely researched and applied in recent years,including low-voltage pulse electromagnetic technology,ultrasonic argon purification,self-purification technology and non-flux continuous purification technology.Among them,the non-flux continuous purification technology integrates a variety of purification methods,which can produce high-quality magnesium alloy continuously and steadily,realize environmental protection production,and achieve remarkable technical and economic benefits.
基金Project(08XD14020) supported by the Program of Shanghai Subject Chief Scientist,ChinaProject(2007CB613701) supported by the National Basic Research Program of ChinaProject(2009AA033501) supported by the National High-tech Research and Development Program of China
文摘The effects of non-flux purification techniques on the mechanical properties and microstructure of AZ91 magnesium alloy were investigated by ICP,OM,XRD and SEM.The results show that Ar spraying with high flow rate could remove non-metallic inclusions and improve the mechanical properties of AZ91.The alloy obtains the best properties after argon spraying for 30 min at the melt temperature of 740 °C.The ceramic foam filter(CFF) could effectively improve the ultimate tensile strength and elongation of AZ91 alloy,especially the elongation,which increase with increasing pores per inch(ppi) and the thickness of CFF.Non-flux purification does not change the microstructure of AZ91 alloy.However,filtration has a certain effect on the fracture pattern of AZ91 alloy.To improve the mechanical properties effectively,both filtration and gas spraying should be utilized together.
文摘A new flux which can remove both Fe and non-metallic inclusions in magnesium alloy was introduced. The Fe content of the magnesium alloy can be decreased greatly from 0.062% to lower than 0.005% (degree of AZ91D) after being purified by this new flux. The optimum addition of B2O3 in the flux is 0.58 % by Gaussian Curve Fitting. Corrosion rate was measured after the specimen being immersed in 5% NaCl solution for 3 d. The results show that the corrosion rate of the magnesium alloy after purification by the new flux is only 0.3 mg·cm-2·d-1. On the other hand, non-metallic inclusions in the magnesium alloy decrease with increasing addition of JDMJ in the new flux. Average volume fraction of the non-metallic inclusions in the magnesium alloy decreases from 1.52% to 1.08%, which leads to improvement in the mechanical properties of the magnesium alloy by 30%. The mechanisms of Fe reduction and non-metallic inclusion-removing in magnesium melt by purification with the new flux were also revealed.