Component nonuniformity numerical prediction method for magnesium alloy casting parts

Abstract

The invention discloses a component nonuniformity numerical prediction method for magnesium alloy casting parts, and relates to a component nonuniformity numerical prediction method for magnesium alloy casting parts. The objective of the invention is to solve the problem that macrosegregation formation of the magnesium alloy casting parts cannot be accurately predicted by an existing method. The component nonuniformity numerical prediction method comprises the following steps: 1, simulating the growth of alpha-Mg dendrites with different growth orientations by adopting a cellular automaton method to obtain a curve that the specific surface area of the dendrites changes along with the solid phase fraction; 2, performing mesh generation on the casting system; 3, calculating an energy, component and momentum conservation equation for all grids with subscript char = 0, and obtaining distribution of temperature, average component and speed in the casting parts; 4, calculating an energy conservation equation for all grids of which the subscript chars are not 0 to obtain temperature distribution; and 5, repeating the step 2, the step 3 and the step 4 until solidification is finished, and outputting an average component field in the casting parts. The component nonuniformity numerical prediction method is applied to the field of magnesium alloy casting part component prediction.

Description

technical field

[0001] The invention relates to a method for numerically predicting composition inhomogeneity of magnesium alloy castings. Background technique

[0002] Magnesium alloy has a series of advantages such as light specific gravity, high specific strength and specific stiffness, and good damping and shock absorption performance, and is an important lightweight material. Magnesium alloy castings have broad application prospects in the fields of national defense, aerospace and automobiles. Casting is the main process for forming them. Therefore, improving the quality of magnesium alloy castings is of great significance to the development of my country's industry. Uneven composition is a casting defect that is easily formed during the solidification of castings, also known as segregation. The segregation on the macro scale is macro segregation, the alloy composition after solidification is higher than the initial alloy composition is called positive segregation, and...

Images