差热-等通道转角挤压工艺对TZK镁合金微观组织与腐蚀性能的影响
Influence of differential thermal-ECAP on microstructure and corrosion properties of TZK magnesium alloy
李亚琴 1张敏洁 1郭菲菲 1周田水 1刘德学2
作者信息
- 1. 兰州理工大学 材料科学与工程学院,甘肃 兰州 730050
- 2. 兰州理工大学 材料科学与工程学院,甘肃 兰州 730050;兰州理工大学 省部共建有色金属先进加工与再利用国家重点实验室,甘肃 兰州 730050
- 折叠
摘要
采用光学显微镜、扫描电镜、电化学、X光电子能谱分析等测试技术探究了差热-等通道转角挤压工艺(DT-ECAP)对Mg-5Sn-2Zn-0.5Zr(TZK)镁合金微观组织和腐蚀性能的影响.结果表明,当模具温度为 300℃、试样保持室温时(DT-1),TZK镁合金晶粒和第二相显著细化,且第二相呈弥散分布.此外,在DT-1 变形条件下,TZK镁合金在Hank's溶液中呈现均匀腐蚀,腐蚀速率为 1.161 mm·a-1,腐蚀电位与腐蚀电流密度分别为-1.38 V和 5.916×10-6 mA·cm-2,合金耐蚀性能最优.而当模具温度为 300℃、试样温度为 200℃(DT-2)以及模具保持室温、试样温度为 300℃(DT-3)时,合金中的第二相沿变形方向呈带状分布,且局部区域存在粗大的块状第二相,其在Hank's溶液中的腐蚀以局部腐蚀为主.
Abstract
The influence of differential thermal-equal channel angular pressing(DT-ECAP)on the microstructure and corrosion proper-ties of Mg-5Sn-2Zn-0.5Zr(TZK)magnesium alloy was explored using optical microscopy(OM),scanning electron microscopy(SEM),electrochemistry,X-ray photoelectron spectroscopy(XPS)and other testing techniques.The results show that when the die temperature is 300℃and the sample is kept at room temperature(DT-1),the grains and the second phase of TZK magnesium alloy are significantly refined,and the second phase is diffusely distributed.In addition,under the DT-1 deformation condition,TZK magnesium alloy shows u-niform corrosion in Hank's solution,with corrosion rate of 1.161 mm·a-1,the corrosion potential and corrosion current density are-1.38 V and 5.916×10-6 mA·cm-2,respectively,and the corrosion resistance of the alloy is the best.When the die temperature is 300℃,the sample temperature is 200℃(DT-2)and the die is kept at room temperature,the sample temperature is 300℃(DT-3),the second phase is distributed in band shape along the deformation direction,and there is the coarse massive second phase in the local ar-ea,its corrosion in Hank's solution is mainly local corrosion.
关键词
Mg-5Sn-2Zn-0.5Zr合金/差热-等通道转角挤压变形/微观组织/腐蚀性能Key words
Mg-5Sn-2Zn-0.5Zr alloy/differential thermal-ECAP deformation/microstructure/corrosion property引用本文复制引用
基金项目
国家自然科学基金资助项目(12162023)
甘肃省重点人才项目(甘财行[2023]11)
甘肃省创新群体项目(23JRRA757)
出版年
2024
NETL
NSTL
万方数据