摘要
通过材料的替代研究,得到了AE44镁合金油底壳压铸件。模拟结果显示该合金的充型能力和凝固顺序等铸造性能都满足此油底壳的工艺条件。利用OM、SEM、XRD对本体组织和物相分析,结果表明:本体组织主要由α-Mg基体和沿晶界分布的Mg-RE化合物组成,这些化合物主要为Al11RE3、Al2RE、Al2.12RE0.88。Al11RE3和Al2.12RE0.88稀土相的存在,对材料性能的提高起到很大的作用。因Al2RE相较粗大,将对性能造成不利影响,应尽量消除。该油底壳本体的室温屈服强度为140 MPa,抗拉强度达到248 MPa,明显高于ADC12铝合金材料228 MPa的抗拉强度指标,有较好的力学性能。断口分析表明,该油底壳本体合金的断裂为准解理断裂。
The die cast oil pan of AE44 magnesium alloy has been developed through the material substitution.The simulation result shows that the casting properties of the alloy,such as filling ability and solidification sequence,can meet the technology requirements of the oil pan.The analysis,by OM,SEM,XRD,of body structure and phase shows that the structure is mainly composed of α-Mg matrix and the Mg-RE compounds which were distributed along the grain boundary.The compounds mainly are Al11RE3,Al2RE,and Al2.12RE0.88.Al11RE3 and Al2.12RE0.88 phases play a significant role in the improvement of the material properties.Al2RE phase should be eliminated due to its coarse size and adverse effect on properties of the alloy.The yield strength of the oil pan is 140 MPa,and the tensile strength is 248 MPa,which is clearly higher than the 228 MPa tensile strength of ADC12 aluminum alloy,and the mechanical properties are good.The analysis on the fracture shows that main mechanism of tensile fracture is the quasi-cleavage fracture.
出处
《铸造》
CAS
CSCD
北大核心
2010年第9期895-898,共4页
Foundry
基金
重庆市科技攻关项目(CSTC
2008AB4111
CSTC
2009AB4010)
