• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2018, Vol. 54 ›› Issue (18): 62-67.doi: 10.3901/JME.2018.18.062

• 材料科学与工程 • 上一篇    下一篇

凝固速度及热处理工艺对Al-8Ca组织性能的影响

赵玉华, 满佳乐, 刘玉林, 陆皖皖   

  1. 沈阳航空航天大学材料科学与工程学院 沈阳 110136
  • 收稿日期:2018-02-01 修回日期:2018-04-16 出版日期:2018-09-20 发布日期:2018-09-20
  • 通讯作者: 赵玉华(通信作者),男,1963年出生,教授。主要研究方向为高性能轻合金。E-mail:zhaoyuhua2010@sau.edu.cn

Effect of Cooling Rates and Heat Treatment on the Structure and Properties of Al-8Ca

ZHAO Yuhua, MAN Jiale, LIU Yulin, LU Wanwan   

  1. College of Materials Science and Engineering, Shenyang Airspace University, Shenyang 110136
  • Received:2018-02-01 Revised:2018-04-16 Online:2018-09-20 Published:2018-09-20

摘要: 针对当前铸造Al-Ca合金研究不够深入的现状,通过铜模铸造、铁模铸造使熔体在102 K/s及25 K/s的冷却速度下凝固,制备相同成分的Al-8Ca (质量分数/%,下同),配合粒状化处理改变合金微观组织,研究凝固速度与热处理工艺对Al-8Ca合金组织形貌及拉伸性能的影响。研究表明:两冷却速度下,合金的显微组织均为α-Al及Al4Ca,但102 K/s合金组织更细,Al4Ca分布更均匀;两凝固工艺制备的合金在550℃下保温,Al4Ca均随时间的延长相互吞噬长大,颗粒数目减少,但冷却速度为102 K/s的合金颗粒较小,数量更多;相比冷却速度为25 K/s的合金,102 K/s合金的抗拉强度、延伸率分别由196 MPa增至386 MPa,由4.91%增至8.19%;达到最佳热处理状态后102 K/s及25 K/s合金的延伸率分别由8.19%增至13.91%,4.91%增至6.75%,抗拉强度分别由386 MPa降至359 MPa,196 MPa降至177 MPa。可见冷却速度的提高,有效优化了Al-Ca合金的微观组织,提升了拉伸性能。

关键词: Al-8Ca, 拉伸性能, 冷却速度, 粒状化处理

Abstract: On account the research of casting Al-8Ca is not through at present,the Al-8Ca(mass fraction/%)alloy ingots are prepared by two casting processes namely copper-cooled and metal-cooled in the cooling rate of 102 K/s and 25 K/s.The structure of these two types of Al-8Ca are improved by granular process,and the effects of different cooling rates and heat treatments on the structure and tensile property of Al-8Ca are studied. The results show that the structure of these two types of Al-8Ca are α-Al and Al4Ca,the alloy of the 102K/s has smaller structure and the Al4Ca is distributed evenly; the Al4Ca of these two types of Al-8Ca alloy are grow, swallow each other and reduce in 550℃ over time,and the alloy of 102K/s has smaller and more granular particles; compared with the alloy of 25 K/s,the tensile strength of 102K/s is increased from 196 MPa to 386 MPa and the elongation rate increased from 4.91% to 8.19%;the elongation and tensile strength of optimal heat treatment status of 102K/s are increased from 8.19% to 13.91% and decreased from 386 MPa to 358 MPa,and the elongation and tensile strength of optimal heat treatment status of 25 K/s are increased from 4.91% to 6.75% and decreased from 196 MPa to 177 MPa.It is observed that increasing the cooling rate of the melt,the Al-8Ca alloy of microstructure are effective optimize and tensile property are improve.

Key words: Al-8Ca, cooling rate, granular treatment, tensile property

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