Evaluation of Hot Tensile Behavior of Fine-Grained Mg–9Al–1Zn Alloy Tube Processed by Severe Plastic Deformation
Evaluation of Hot Tensile Behavior of Fine-Grained Mg–9Al–1Zn Alloy Tube Processed by Severe Plastic Deformation
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DOI：
10.1007/s12666-016-0933-5
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发表时间：
2017-07
影响因子：
1.6
通讯作者：
A. Fata;G. Faraji;M. Mashhadi;H. Abdolvand
中科院分区：
文献类型：
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作者：
A. Fata;G. Faraji;M. Mashhadi;H. Abdolvand
采用平行管道角挤压(PTCAP)工艺，在300℃下对铸态镁合金管材进行不同道次的转角挤压，研究了管材在室温和高温下的力学性能和组织演变。结果表明，应变越大，室温下的强度、硬度和延伸率越高。实现了显著的晶粒细化。对于第三道次加工的管材，强度从最初的150微米降低到4微米。经过第二道次PTCAP工艺后，强度显著增加到约92%。经皮冠状动脉腔内成形术(PTCAP)首次通过后强度增加56.5%。在室温下，延伸率也相对增加。第三道次加工后的试件出现微孔洞和微裂纹。与第一次和第二次加工的样品相比，这导致了强度和延伸率的损失。两道次加工后的试样在400℃拉伸试验中的延伸率为178%。第三道次PTCAP工艺后，硬度提高了约77%。力学性能测试结果与显微组织分析结果一致。
In the present study, parallel tubular channel angular pressing (PTCAP) process was implemented to as cast Mg–9Al–1Zn magnesium alloy tubes via different number of passes at 300 °C. Mechanical properties and microstructure evolution of the tubes were investigated at room and elevated temperatures. The results showed that an increase in strain leads to a higher strength, hardness, and elongation at room temperature. A significant grain refinement was achieved. It was decreased to 4 µm for a third pass processed tube from an initial value of 150 µm. Strength increased notably to about 92 % after the second pass PTCAP process. Increase in the strength after first pass PTCAP was 56 %. Elongation relatively increased at room temperature, too. Microvoids and microcracks appeared in the third pass processed specimen. This led to a loss in strength and elongation in comparison with first and second pass processed samples. Two pass processed sample revealed ~178 % ductility in 400 °C tensile test. Hardness increased by about 77 % after third pass PTCAP process. The result of the mechanical properties and the microstructure were consistent with each other.