摘要
研究了Al-Mg-Si合金中过剩硅和Mg2Si的含量以及热处理工艺对该合金汽车板材的显微组织和力学性能的影响。结果表明,增加过剩硅含量,模拟烘烤前板材的抗拉强度提高30%左右,伸长率提高15%左右;而模拟烘烤后板材强度的增加不超过15%,伸长率则没有明显变化。随着Mg2Si含量增加,模拟烘烤前后板材的强度均有所增加,但不会对板材伸长率产生显著影响。在T4P状态下,当Mg2Si含量由1.25%增加到1.97%时,模拟烘烤后板材的抗拉强度分别由316MPa增加到383MPa。预时效对合金模拟烘烤前的屈服强度和塑性影响不大,因此不会对板材的变形性能产生显著影响。但对模拟烘烤后的力学性能影响显著,板材的抗拉强度最高可以达到383MPa,接近T6状态的抗拉强度,同时塑性有所增加,有利于提高板材的服役性能。
The effects of excess Si and Mg2Si content and the heat treatment cal properties of the AI-Mg-Si alloy automotive body sheets were investigated. process on the microstructure and mechani- The results show that, the tensile strength of the sheets can increase obviously about 30% before simulated paint baking, and the elongation increases approximately 15% with increasing the excess Si content. After simulated paint baking, however,the tensile strength of the sheets increases less than 15% and the elongation does not change significantly. With the increase of Mg, Si content.the strengthof the sheets before and after simulated paint baking increases, but the effect on the elongation of the sheets is trifling. When the Mg2Si content increases from 1.25% to 1.97% ,the tensile strength of the sheets increases from 316MPa to 383MPa in T4P condition after simulated paint baking. The effect of pre-aging on the yield strength and elongation of sheets is unnoticeable before simulated paint baking,which means that it cann＇t affect the deformation ability of sheets. Mter simulated paint baking, however, its effect is remarkable. The value of 383 MPa of tensile strength of the sheets can be obtained, which is close to that of the tensile strength in T6 condition. The elongation of the sheets increases simultaneously, which is beneficial to the improvement of performance of the sheets.
出处
《金属热处理》
EI
CAS
CSCD
北大核心
2006年第6期20-24,共5页
Heat Treatment of Metals
