主办：陕西省汽车工程学会
ISSN 1671-7988  CN 61-1394/TH
创刊：1976年
汽车实用技术

汽车实用技术 ›› 2023, Vol. 48 ›› Issue (17): 128-133.DOI: 10.16638/j.cnki.1671-7988.2023.017.023

• 工艺·材料 • 上一篇    

微量 Mg 元素对 Al-Si-Cu 合金铸件组织及 力学性能的影响

杨兴国   

  1. 重庆工商职业学院 智能制造与汽车学院
  • 出版日期:2023-09-15 发布日期:2023-09-15
  • 通讯作者: 杨兴国
  • 作者简介:杨兴国（1986－），男，博士，讲师，研究方向为梯度纳米结构材料设计与制备、金属材料热加工，E-mail: yanglixgy@163.com。
  • 基金资助:
    重庆市教育委员会科学技术研究项目（KJQN202004005）；重庆工商职业学院重点科研项目（NDZD2020-02）。

Influence of Trace Mg on the Microstructure and Mechanical Properties of Al-Si-Cu Alloy Castings

YANG Xingguo   

  1. Intelligent Manufacturing and Automotive Institute, Chongqing Technology and Business Institute
  • Online:2023-09-15 Published:2023-09-15
  • Contact: YANG Xingguo

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摘要： 针对发动机气缸体因力学性能差引起热机异响故障问题，文章结合优化调整工艺参数、 改进模具浇注及冷却系统方案、增加热处理工艺等有效降低铸件缩孔、缩松率、提高铸件气 密性的措施，重点研究了微量 Mg 元素对铸态 Al-Si-Cu 合金组织及力学性能的影响。结果表 明，Mg 在含量 0.05%～0.55%范围内，随着 Mg 含量的增加，组织中存在于共晶 Si 和基体 Al 交界处的强化相 Mg2Si 逐渐增加；当 Mg 含量大于 0.3%时，铸件的抗拉强度和屈服强度分别 达到 230.6 MPa 和 157.3 MPa，提升了 43.6%和 69.9%，实际应用中可以确定 Mg 含量为 0.3%～ 0.55%，以确保铸件具有稳定的力学性能，避免诱发其他机械故障。

关键词: Mg 元素；Al-Si-Cu 合金；铸件组织；力学性能

Abstract: In view of the abnormal noise of the engine cylinder block caused by the mechanical properties of the engine, the paper took measures to optimize the process parameters, improve the mold casting system and increase the heat treatment process, and studied the effect of trace Mg elements on the organization and mechanical properties of cast Al-Si-Cu alloy. The results show that in the range of Mg content from 0.05% to 0.55%, the mechanical properties of the castings show an increasing trend with the increase of Mg content, and the strengthening phase Mg2Si, which exists in the junction of eutectic Si and matrix Al in the organization, gradually increases; when the Mg content is greater than 0.3%, the tensile strength and yield strength of the castings reach 230.6 MPa and 157.3 MPa, respectively, raising the Mg content can be determined to be 0.3%～0.55% in practical applications to ensure that the castings have stable mechanical properties and thus avoid inducing other mechanical failures.

Key words: Mg element; Al-Si-Cu alloy; Castings organization; Mechanical properties