电弧增材制造(WAAM)Al-7Si-0.6Mg-xFe组织与性能的研究

Investigation on Microstructure and Properties of Al-7Si-0.6Mg-xFe Alloy by Wire Arc Additive Manufacturing (WAAM)

摘要:

本文研究了Fe含量对WAAM Al-7Si-0.6Mg合金组织与性能的影响,并观察了合金中富Fe相形貌和分布。结果表明,WAAM成形试样中富Fe相为细小针状,为亚稳态镁硅相和π-Fe相的混合相。经T6热处理后,富Fe相中Mg₂Si脱溶而形成π-Fe相。随着Fe含量的增加,合金中的富Fe相的尺寸增大、数量增多。Fe含量在较小的范围内变化即可对WAAM成形合金的延伸率产生较大影响,而对强度作用不明显,当Fe含量由0.11%增加到0.18%,合金的断裂延伸率降低了47.1%。

Abstract:

The effect of Fe additions on the structure and properties of Al-7Si-0.6Mg alloy by wire arc additive manufacturing (WAAM) was studied and the morphology and distribution of Fe-rich phase in the alloy were observed. The results show that the fine acicular Fe-rich phase in as-deposition alloys is a mixture of metastable Mg-Si phase and π-Fe phase. After heat treatment (T6), Mg₂Si dissolves from Fe-rich phase and forms π-Fe phase. With the increase of Fe additions, the size and quantity of Fe-rich phase in the alloy increase. The change of Fe-content in a small range can have a great effect on the elongation of WAAM alloy (T6), but has no obvious effect on strength. With the additions of Fe increases from 0.11% to 0.18%, the fracture elongation of the alloy decreases by 47.1%.