新型倾斜板技术制备半固态AlSi6Mg2合金及触变成形

Preparing Semisolid AlSi6Mg2 Alloy by Novel Sloping Plate Process and Thixoforming

采用自制的波浪型倾斜板技术装置,对制备半固态AlSi6Mg2合金坯料及触变成形进行研究。结果表明,采用波浪型的倾斜板可制备组织性能优良的半固态合金坯料,坯料由细小的球形晶和少量玫瑰晶组成。在本试验条件下,制备AlSi6Mg2半固态坯料的浇注温度范围为660-680℃。在坯料二次加热温度为597℃,保温90min,模具预热温度为400℃,保温120min的试验条件下,可得到表面光洁、组织优良的成品制件。触变压铸时,液相流动成为主要的变形方式,制品上部由于液相偏聚,对应的硬度较低,下部由于固相的微塑性变形,对应的硬度较高。

By using self-made wavelike sloping plate setup, preparing semisolid billets of AlSi6Mg2 alloy and thixoforming were studied. It is shown that the semisolid billets with good microstructures andproperties can be prepared by the proposed process, and the billets were composed of fine spherical grains and a little part of rosette grains. Under the current experimental conditions, proper casting temperature range of 660-680 ℃ for AlSi6Mg2 alloy is suggested. When the reheating temperature is 597 ℃, holding time is 90 min, mould preheating temperature is 400 ℃ and the holding time is 120 min, thixoforming product with fine surface and good microstructures can be manufactured. During the die casting, liquid flow is the mainly deformation pattern, due to the liquid aggregation in the upper part of the product, the corresponding hardness is lower, however, there is a small solid plastic deformation in the bottom of the product, the corresponding hardness is higher.