目的

研究微弧氧化（MAO）电解液中钙磷浓度的变化对所制备涂层微观力学性能的影响。

方法

制作直径10 mm、厚1 mm 的圆盘形Ti-6Al-4V 合金试件32 个，随机分4 组，在4 种含不同配比的乙酸钙和β-甘油磷酸二钠盐的电解液中制备MAO 涂层。 4 种电解液中β-甘油磷酸二钠盐浓度均固定为0.02 mol/L，乙酸钙浓度从0.05 ～0.3 mol/L 逐级递增。通过X 线能谱分析检测试件表面MAO 涂层的钙磷比（Ca/P），纳米压痕试验测量涂层的微弹性模量及微硬度。

结果

电解液中乙酸钙浓度从0.05 ～0.3 mol/L 逐级增加时，制备出的MAO涂层Ca/P 也相应从0.52±0.02、1.23±0.05、1.75±0.10 增加到2.44±0.05，微弹性模量分别为（56.11±8.22）、（48.46±9.74）、（32.07 ±7.07）和（28.19±6.94）GPa，微硬度分别为（3.13±0.78）、（2.56±0.85）、（1.49±0.68）和（0.68±0.27）GPa。

结论

电解液中钙磷浓度变化对MAO 涂层的微观力学性能有显著影响。 微弹性模量及微硬度随涂层Ca/P 增加而减小。

Objective

To explore the effect of the change of Ca and P concentration in the electrolyte on the micro-mechanical properties of the titanium alloy coating formed by microarc oxidation （MAO） technique.

Methods

Thirty two disc-shaped Ti-6Al-4V specimens （10 mm in diameter and 1 mm in thickness） were equally divided into 4 groups.The surfaces were treated by MAO technique in electrolytic solution containing calcium acetate （CA） and β-glycerol phosphate disodium salt pentahydrate （β-GP）.The concentration of β-GP was fixed at 0.02 mol/L，while the concentrations of CA were set at 0.05-0.3 mol/L respectively for the 4 testing groups.The Ca/P ratios of the surface MAO coatings were detected by energy dispersive X-ray analysis（EDX）.The micro hardnesses and elastic moduli were measured by a nano-indentation tester.

Results

When the CA concentration was increased from 0.05 to 0.3 mol/L in the electrolyte，the Ca/P ratios of the MAO coating increased accordingly from 0.52±0.02， 1.23±0.05， 1.75±0.10 to 2.44±0.05.The elastic moduli and the hardnesses of the 4 groups of MAO coating were（56.11±8.22）GPa， （48.46±9.74）GPa， （32.07±7.07）GPa， （28.19±6.94）GPa and （3.13±0.78）GPa， （2.56±0.85）GPa，（1.49±0.68）GPa，（0.68±0.27）GPa respectively.

Conclusions

The Ca/P concentration of the electrolyte has a significant effect on the micro-mechanical properties of the MAO coating of titanium alloy.The micro-elastic modulus and micro-hardness of the MAO coating decrease with the Ca/P ratio.