郭长刚,许益蒙,王凌倩,曹宝成.激光表面强化对镁合金在模拟体液中腐蚀行为的影响[J].表面技术,2017,46(8):188-194.
GUO Chang-gang,XU Yi-meng,WANG Ling-qian,CAO Bao-cheng.Effect of Laser Surface Strengthening on Corrosion Behavior of Magnesium Alloy in Simulated Body Fluid[J].Surface Technology,2017,46(8):188-194 |
| 激光表面强化对镁合金在模拟体液中腐蚀行为的影响 |
| Effect of Laser Surface Strengthening on Corrosion Behavior of Magnesium Alloy in Simulated Body Fluid |
| 投稿时间：2017-02-13 修订日期：2017-08-20 |
| DOI：10.16490/j.cnki.issn.1001-3660.2017.08.031 |
| 中文关键词: 镁合金 SBF 激光强化 脉宽 腐蚀性能 表面处理 |
| 英文关键词:magnesium alloy SBF laser strengthening pulse width corrosion resistance surface treatment |
| 基金项目:国家自然科学基金青年科学基金项目（51505464） |
|
|
|
|
| 摘要点击次数: |
| 全文下载次数: |
| 中文摘要: |
| 目的 通过对镁合金表面进行激光强化处理，改善医用AZ91D镁合金在模拟体液中的耐腐蚀性能。方法 采用不同脉宽的Nd:YAG脉冲激光对医用AZ91D镁合金表面进行处理，激光能量密度分别为28、23、18 J/mm2，对激光处理后镁合金强化层的组成、显微结构、厚度、元素分布以及耐腐蚀性能等进行测试和分析。结果 AZ91D经过激光强化处理后形成致密的强化层，强化层中相的组成与基材相的组成相同，均由α-Mg和β-Mg17Al12组成，强化层的厚度达到300 m。Mg和Mg17Al12的X射线衍射峰均向低角度偏移（约0.2°），且镁合金表面晶粒均得到细化，β相的大小从平均55.705 μm减小到平均6.447 μm。EDS分析表明，经过激光处理后，Mg的质量分数由82.88%减少为70.13%，Al的质量分数由16.28%增加为28.08%，且Al的分布更均匀。激光处理后，镁合金在模拟体液中的电化学测试结果表明，镁合金的腐蚀电位从原来的1274 mV增加到1215 mV，腐蚀电流密度从8.920×105 A/cm2减小为8.826×106 A/cm2，同时，阻抗也从原来的1000 Ω增加到60 000 Ω，可知激光强化镁合金的耐腐蚀性能较原始镁合金的耐腐蚀性能均有一定程度的改善。结论 医用AZ91D镁合金在不同脉宽的Nd:YAG脉冲激光处理后，表面晶粒得到了细化，强化层中富集Al，在模拟体液中的耐腐蚀性能得到改善。 |
| 英文摘要: |
| The work aims to improve corrosion resistance of AZ91D magnesium alloy in simulated body fluid by means of laser melting on the surface of magnesium alloy. Being treated with Nd:YAG pulse laser of different pulse width, laser energy density of medical AZ91D magnesium alloy was 28, 23, 18 J/mm2, respectively. Composition, microstructure, thickness, element distribution and corrosion resistance of the magnesium alloy strengthened layer were tested and analyzed. A dense melt layer was present on LSM-treated magnesium alloy AZ91D. Phase composition of the strengthened layer was identical to that of the substrate, both were composed of α-Mg and β-Mg17Al12. Thickness of the strengthened layer was over 300 microns. X-ray diffraction peaks of Mg and Mg17Al12 slightly shifted toward lower angles (about 0.2). Grains on the surface of the magnesium alloy were refined, size of β phase was reduced from an average of 55.705 μm to 6.447 μm. EDS analysis showed that, after laser treatment, Mg mass fraction was reduced from 82.88% to 70.13% while Al mass fraction increased from 16.28% to 28.08% and Al was distributed more uniformly. Electrochemical Al tests results in simulated body fluid after laser treatment indicated that corrosion potential of magnesium alloy increased from 1274 mV to 1215 mV, corrosion current increased from 8.920×105 A/cm2 to 8.826×106 A/cm2 and impedance also increased from 1000 Ω to 60 000 Ω, corrosion resistance of the laser strengthened magnesium alloy was better than that of the original magnesium alloy to certain degree. Surface grains are refined, Al is enriched on the strengthened layer and corrosion resistance of the medical AZ91D magnesium alloy was improved in simulated body fluid after Nd:YAG pulse laser treatment with different pulse width. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|
渝公网安备 50010702501715号