Study on Microstructure and Properties of WE83 Magnesium Alloy Ring by Centrifugal Casting
Large high strength and toughness magnesium alloy integral ring has a wide application prospect in aerospace field,but it is difficult to prepare large magnesium alloy ingot due to dendrite coarseness and serious segregation,therefore,the technical route of large ingot-large ring of traditional integral metal ring is not suitable for the production of magnesium alloy ring.In this paper,centrifugal casting technology was used to prepare thick-walled WE83 magnesium alloy rings.The centrifugal force field was introduced to control the solidification structure of the ring castings,and the influence of centrifugal force field on the solidification structure and mechanical properties was studied.The results show that the grain size of centrifugal casting magnesium alloy ring is remarkably refined,the difference of average grain size of casting at different sampling positions is reduced,a large number of lamellar LPSO phases are precipitated on the matrix,and ultimate tensile strength(UTS)and tensile elongation were 259MPa and 9.9%,respectively,which was significantly higher than that of the permanent mold casting.It lays a foundation for the development of fine crystallization and homogenization technology for large-scale magnesium alloy ring castings.