响应面法优化2A97铝锂合金化铣工艺的研究

目的研究响应面法在优化2A97铝锂合金最佳化铣液配方中的可行性。方法在传统铝合金化铣氢氧化钠、硫化钠、三乙醇胺及溶解铝溶液体系,探索2A97铝锂合金化学铣切工艺,研究化铣液配方对2A97铝锂合金表面质量的影响,从而优化工艺参数并获得最佳化铣工艺。在单因素试验的基础上,以表面粗糙度为响应值,应用响应面法中的Box-Behnken设计四因素(氢氧化钠、硫化钠、三乙醇胺及溶解铝浓度)三水平试验,通过回归分析,得到了化铣液各组分参数对响应值的影响规律,并且通过优化分析得到了最佳2A97铝锂合金化铣液配方。结果通过响应面设计试验分析可得,当2A97铝锂合金化铣液配方为氢氧化钠130 g/L、硫化钠15 g/L、三乙醇胺50 g/L、溶解铝70 g/L时,采用该化铣液对2A97铝锂合金试样进行化铣,得到的试样表面平整一致,腐蚀速度为0.031 mm/min,粗糙度Ra=1.36μm,无晶间腐蚀及点蚀等缺陷。结论拟合模型决定系数R~2=0.967 927,说明模型的拟合性良好,可以采用响应面法对2A97铝锂合金化铣工艺进行分析,具有一定的参考价值。

Optimization of 2A97 Al-Li Alloy Chemical Milling Technology in Response Surface Method

The work aims to study feasibility of response surface method in optimizing optimum chemical-milling solution formula of 2A97 Al-Li alloy. In traditional aluminum alloy milling of NaOH, Na2S, TEA and Al3+ solution system, effects of chemical-milling solution formula on surface quality of 2A97 aluminum lithium alloy, so as to optimize process parameters and obtain optimal chemical milling process. Based on single factor test, law of effects of chemical milling solution composition pa-rameters on response value was obtained through regression analysis by performing Box-Behnken four design factors (NaOH, Na2S, TEA and Al3+) three level test in response surface method with surface roughness as response value. The optimum 2A97 Al-Li alloy chemical milling solution formula was obtained by optimization analysis. According to the test analysis of response surface design, when the 2A97 Al-Li alloy chemical milling solution formula was as follows: 130 g/L NaOH, 15 g/L Na2S, 50 g/L TEA and 70 g/L Al, the chemical milling solution was applied to chemical milling of 2A97 Al-Li alloy specimen, specimen surface was smooth and consistent, corrosion rate was 0.031 mm/min, surface roughnessRa=1.36μm, and free from pitting corrosion and intergranular corrosion. Fitting model coefficientR2=0.967927 shows that the model is fit well, and response sur-face method is of certain reference value and can be used to analyze chemical milling process of 2A97 Al-Li alloy.