Microstructure and Mechanical Properties of 7005 Aluminum Alloy Components Formed by Thixoforming
Microstructure and Mechanical Properties of 7005 Aluminum Alloy Components Formed by Thixoforming
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触变成型7005铝合金零件的显微组织和力学性能
DOI：
10.1016/j.jmst.2016.07.014
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发表时间：
2017-05
影响因子：
10.9
通讯作者：
Wang Ying
中科院分区：
文献类型：
--
作者：
Jiang Jufu;Atkinson H. V.;Wang Ying
在本研究中，采用再结晶和部分重熔（RAP）技术制备了7005铝合金半固态坯料，然后在不同的等温温度、预热温度和加载路径下进行触变成型。研究了触变成型产品的机械性能和微观结构。结果表明，通过三步感应加热温挤压7005铝合金获得的显微组织是均匀的、适合触变成型的球状组织。模具预热温度对7005铝合金半固态坯料的充型状况影响较大。在365°C的预热温度下获得了完全的填充状态和良好的表面质量。由相对球形颗粒组成的触变成形微观结构说明填充过程依赖于固体颗粒的滑动和旋转，而不是固体颗粒的塑性变形。由于与液相相比，固体颗粒的可调速度较慢，因此在触变成型产品的不同区域发现液相分布不均匀。由于固体晶粒粗化，等温温度的升高导致触变成型产品的机械性能略有下降。 T6热处理触变成形件的最高屈服强度、极限抗拉强度和延伸率分别为237MPa、361MPa和16.8%，在等温温度605℃时达到。加载路径对触变成型产品的力学性能和微观结构有显着影响。载荷路径2下得到的触变制品显微组织中出现了裂纹、微孔等缺陷，导致其力学性能较路径1明显下降。在612℃等温温度下，更多的液体分数引起的变形具有更好的兼容性，有利于减少触变制品不同区域的液相不均匀性。
In the present research, semisolid billet of 7005 aluminum alloy was fabricated by using recrystallization and partial remelting (RAP), then thixoformed at different isothermal temperatures, preheating temperatures and load routes. Mechanical properties and microstructure of the thixoformed product were investigated. The results showed that microstructure achieved by three-step induction heating warm extruded 7005 aluminum alloy consists of a uniform and spheroidal microstructure suitable for thixoforming. Preheating temperature of the die affected significantly the filling status of semisolid billet of 7005 aluminum alloy. Complete filling status with good surface quality was obtained at a preheating temperature of 365 °C. Thixoformed microstructures consisting of relatively spheroidal grains illustrate the dependence of filling process on the sliding and rotating of solid grains rather than plastic deformation of solid grains. A non-uniform distribution of liquid phase was found in the different regions of the thixoformed product due to the slower adjustable velocity of solid grains as compared with liquid phase. Increase of isothermal temperatures led to a slight decrease of mechanical properties of the thixoformed product due to coarsening of solid grains. The highest yield strength, ultimate tensile strength and elongation of thixoformed components with T6 heat treatment are 237 MPa, 361 MPa and 16.8%, respectively, which were achieved at the isothermal temperature of 605 °C. Load route has a significant effect on mechanical properties and microstructure of the thixoformed product. Defects, such as crack and microporosity occurred in the microstructure of the thixoformed product obtained under load route 2. It led to an obvious reduction of mechanical properties as compared with route 1. A better compatibility of deformation caused by more liquid fraction at the isothermal temperature of 612 °C is beneficial to reducing non-uniformity of liquid phase in the different regions of the thixoformed product.
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影响因子：
6.3
作者：
De-hong Lu;Ye-hua Jiang;Guisheng Guan;R. Zhou;Zhenhua Li;R. Zhou
通讯作者：
De-hong Lu;Ye-hua Jiang;Guisheng Guan;R. Zhou;Zhenhua Li;R. Zhou
DOI：
10.1016/j.msea.2004.05.004
发表时间：
2005-01-15
影响因子：
6.4
作者：
Chayong, S;Atkinson, HV;Kapranos, P
通讯作者：
Kapranos, P
DOI：
10.1016/s0921-5093(03)00528-8
发表时间：
2003-11-25
影响因子：
6.4
作者：
Liu, D;Atkinson, HV;Jones, H
通讯作者：
Jones, H
DOI：
10.1007/s11663-011-9592-4
发表时间：
2012-04
期刊：
Metallurgical and Materials Transactions B
影响因子：
--
作者：
R. Guan;Zhan-Yong Zhao;C. Lee;Qiu-sheng Zhang;Chun-ming Liu
通讯作者：
R. Guan;Zhan-Yong Zhao;C. Lee;Qiu-sheng Zhang;Chun-ming Liu
DOI：
10.1007/bf02642580
发表时间：
1972-01-01
期刊：
METALLURGICAL TRANSACTIONS
影响因子：
--
作者：
SPENCER, DB;FLEMINGS, MC;MEHRABIAN, R
通讯作者：
MEHRABIAN, R