摘要
Rectangular cross-section specimens with different section thicknesses were prepared to study the influences of pouring temperature, mould temperature and squeeze velocity on the fluidity of squeeze cast AZ91D magnesium alloy by means of orthogonal test design method. The results show that pouring temperature, mould temperature and squeeze velocity can significantly affect the fluidity of magnesium alloy specimens with wall thickness no more than 4 ram, and the pouring temperature is the most influential factor on the fluidity of specimens with wall thickness of 1, 2 and 3 mm, while mould temperature is the one for specimens with wall thickness of 4 mm. Increasing pouring temperature between 700 ℃ and 750 ℃ is beneficial to the fluidity of AZ91D magnesium alloy, and increasing mould temperature significantly enhances the filling ability of thick （3 and 4 mm） section castings. The fluidity of squeeze cast magnesium alloy increases with the increase of wall thickness. It is not recommended to produce magnesium alloy casting with wall thickness of smaller than 3 mm by squeeze cast process due to the poor fluidity. The software DPS was used to generate the regression model, and linear regression equations of the fluidity of squeeze cast AZ91D with different wall thicknesses are obtained using the test results.
Rectangular cross-section specimens with different section thicknesses were prepared to study the infl uences of pouring temperature, mould temperature and squeeze velocity on the fl uidity of squeeze cast AZ91D magnesium alloy by means of orthogonal test design method. The results show that pouring temperature, mould temperature and squeeze velocity can significantly affect the fluidity of magnesium alloy specimens with wall thickness no more than 4 mm, and the pouring temperature is the most infl uential factor on the fl uidity of specimens with wall thickness of 1, 2 and 3 mm, while mould temperature is the one for specimens with wall thickness of 4 mm. Increasing pouring temperature between 700 °C and 750 °C is benefi cial to the fl uidity of AZ91D magnesium alloy, and increasing mould temperature signifi cantly enhances the fi lling ability of thick(3 and 4 mm) section castings. The fl uidity of squeeze cast magnesium alloy increases with the increase of wall thickness. It is not recommended to produce magnesium alloy casting with wall thickness of smaller than 3 mm by squeeze cast process due to the poor fl uidity. The software DPS was used to generate the regression model, and linear regression equations of the fl uidity of squeeze cast AZ91D with different wall thicknesses are obtained using the test results.
基金
the open program of State Key Laboratory of Materials Processing and Die&Mould Technology(No.08-04),Huazhong University of Science and Technology,China
