激光喷丸诱导镁合金表面微织构的电化学腐蚀性能

发布时间：2018-11-28 10:39

【摘要】：利用脉宽为8 ns的Nd:YAG脉冲激光对AZ31B镁合金表面进行激光喷丸处理,研究激光喷丸诱导微织构对AZ31B镁合金耐腐蚀性能的影响,进行表面微织构的形貌分析,测量试样表面的动电位极化曲线。结果表明,激光喷丸产生的微织构周围未出现烧蚀现象,其微凹坑的直径和深度随激光能量的增加而增大,随喷丸次数的增加呈现先增大后趋于饱和趋势。与未处理试样相比,在相同微织构间距下,激光能量为1.0 J、1.5 J、2.0 J时试样的自腐蚀电位分别向正移95 m V、123 m V、151 m V,自腐蚀电流密度分别减少36.48%、50.26%、60.42%;在相同激光能量下,微织构间距为1.0 mm、1.5 mm、2.0 mm试样的自腐蚀电位分别向正移145 m V、134 m V、123 m V,自腐蚀电流密度分别减少50.26%、46.19%、44.34%。研究表明激光喷丸诱导的微织构提高了AZ31B镁合金表面的耐腐蚀性,且激光能量越高,喷丸间距越小,抗腐蚀性能越好。
[Abstract]:The surface of AZ31B magnesium alloy was treated by Nd:YAG pulse laser with pulse width of 8 ns. The effect of laser shot peening induced microtexture on the corrosion resistance of AZ31B magnesium alloy was studied, and the morphology of surface microtexture was analyzed. The potentiodynamic polarization curve of the sample surface was measured. The results show that there is no ablation around the microtexture produced by laser shot peening, and the diameter and depth of the microcrater increase with the increase of laser energy, and then tend to saturation with the increase of shot peening times. Compared with untreated samples, at the same microtexture spacing, the self-corrosion potential of the samples with laser energy of 1.0 J ~ (1.5) J ~ (2. 0) moves forward to 95 MV ~ (123) m V ~ (-1) V ~ (151) MV, respectively, when the laser energy is 1.0 J ~ (1.5) J ~ (-1) J, respectively. The corrosion current density was reduced by 36.48% and 50.26%, respectively. At the same laser energy, the self-corrosion potential of the sample with a microtexture spacing of 1.0 mm,1.5 mm,2.0 mm shifted forward to 145mV / 134mV / 123mV, and the self-corrosion current density decreased 50.26m / 46.19m, respectively. 44.34. The results show that the micro-texture induced by laser shot peening can improve the corrosion resistance of AZ31B magnesium alloy, and the higher the laser energy is, the smaller the peening distance is, and the better the corrosion resistance is.
【作者单位】：江苏大学机械工程学院;
【基金】：国家自然科学基金(51175236) 高等学校博士学科点专项科研基金联合(20123227110022) 江苏省科技支撑(工业)(BE2013097) 中国博士后科学基金54批面上(2013M540417) 江苏大学高级人才启动基金(13JDG109) 江苏大学大学生科研立项(13A604)资助项目
【分类号】：TG665;TG146.22

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