A novel nonlinear pressurization method for counter-gravity casting of cross-sectional mutation structures.

Area of Science:

• Materials Science
• Manufacturing Engineering
• Metallurgy

Background:

• Complex counter-gravity casting requires precise control to ensure filling integrity and metallurgical quality.
• Shortening filling time is crucial but often conflicts with preventing air entrainment.

Purpose of the Study:

• To develop a novel nonlinear pressurization method to overcome the contradiction between filling time and air entrainment in complex counter-gravity casting.
• To establish a criterion for iterative calculation of nonlinear pressurization curves and obtain an empirical expression for nonlinear pressurizing speed.

Main Methods:

• Systematic analysis of the relationship between critical gating velocity and stable filling height.
• Development of an iterative calculation criterion for nonlinear pressurization curves.
• Obtaining an empirical expression linking nonlinear pressurizing speed to filling height.

Main Results:

• A nonlinear pressurization curve design method was established based on the empirical expression.
• Water filling experiments validated the method, demonstrating reduced filling time.
• The method effectively avoided air entrainments during the casting process.

Conclusions:

• The proposed nonlinear pressurization method successfully balances filling time and air entrainment prevention in complex counter-gravity casting.
• This technique offers a valuable processing control strategy for enhancing the performance of low-pressure casting of intricate components.
• The findings contribute to improved metallurgical quality and manufacturing efficiency in advanced casting applications.