研究了Mg-(4~7)Al-2Sr系列四种合金的显微组织、拉伸和蠕变性能及Al含量对其组织和性能的影响.Mg-(4~7)Al-2Sr系合金的铸态组织均由α-Mg和沿枝晶界分布的第二相构成.Al含量为4%时在晶界处形成了离异共晶和少量层片共晶Al4Sr相及大块的三元τ(Mg-Al-Sr)相.Al含量的增加使Al4Sr全部转变为更加粗大的层片状共晶,同时共晶相的体积分数增加而τ相体积分数减小,当Al含量6%时全部为α-Mg+Al4Sr共晶组织.Al含量继续升高到7%后,基体中形成了少量的Mg17Al12相.含Al 4%和5%的合金中Sr抑制了显微组织中Mg17Al12相的形成和高温下的非连续析出,并且在高温100h蠕变后显微组织没有发生明显变化,有较好的蠕变抗力.三元τ相比Al4Sr有更高的热稳定性,因此在Al含量低于6%时,随着Al量增大,τ相减少而Al4Sr相增加,导致合金蠕变性能有所下降;Al含量高于6%时,胞状Mg17Al12相非连续析出,Al含量增大使析出相增多,蠕变性能也逐渐下降.
参考文献
[1] | Pekguleryuz M.O.; .Development of Creep Resistant Magnesium Diecasting Alloys[J].Materials Science Forum,2000(0):131-140. |
[2] | A. A. Luo .Recent magnesium alloy development for elevated temperature applications[J].International Materials Reviews,2004(1):13-30. |
[3] | Mihriban O. Pekguleryuz;Eric Baril .Creep Resistant Magnesium Diecasting Alloys Based on Alkaline Earth Elements[J].Materials transactions,2001(7):1258-1267. |
[4] | Bai Jing;Sun Yangshan;Xun Shan;Xue Feng;Zhu Tianbai .Microstructure and tensile creep behavior of Mg-4Al based magnesium alloys with alkaline-earth elements Sr and Ca additions[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2006(1/2):181-188. |
[5] | Eric Baril;Pierre Labelle;Mihriban O. Pekguleryuz .Elevated Temperature Mg-Al-Sr: Creep Resistance, Mechanical Properties, and Microstructure[J].JOM,2003(11):34-39. |
[6] | PARVEZ M A;MEDRAJ M;ESSADIQI E et al.Experimental study of the ternary magnesium-aluminium-strontium system[J].Journal of Alloys and Compounds,2005,402(1-2):170-185. |
[7] | BLUM W;WATZINGER B;ZHANG P .Creep of die-cast light-weight Mg-Al-base alloy AZ91hp[J].Advanced Engineering Materials,2000,2(06):349-355. |
[8] | Zhang P.;Blum W.;Watzinger B. .Changes in microstructure and deformation resistance during creep of the die-cast Mg-Al-base alloy AZ91hp at intermediate temperatures up to 150 °C[J].Physica Status Solidi, A. Applied Research,1999(2):481-489. |
[9] | PEKGULERYUZ M;LABELLE P;ARGO D.Magnesium diecasting alloy AJ62X with superior creep resistance,ductility and diecastability[A].San Diego,CA,United States:Minerals,Metals and Materials Society,2003:201-206. |
[10] | PEKGULERYUZ M O;BARIL E.Development of creep resistant Mg-Al-Sr alloys[A].New Orleans,LA,United States:Minerals,Metals and Materials Society,2001:119-202. |
[11] | Yuan Guangyin;Sun Yangshan .EFFECTS OF Sb ADDITION ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF AZ91 MAGNESIUM ALLOY[J].Scripta materialia,2000(11):1009-1013. |
[12] | D. Bradai : M. Kadl-Hanifi .The kinetics of the discontinuous precipitation and dissolution in Mg-rich Al alloys[J].Journal of Materials Science,1999(21):5331-5336. |
[13] | Mihriban O. Pekguleryuz;A. Arslan Kayo .Creep Resistant Magnesium Alloys for Powertrain Applications[J].Advanced Engineering Materials,2003(12):866-878. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%