几种金属材料在乳酸中的腐蚀性能研究

采用失重法对316L不锈钢、Ti、Ni 3种材料在不同条件下的耐乳酸腐蚀行为进行了研究,详细考察了反应温度和反应时间对316L腐蚀的影响。结果表明,316L在L-乳酸中腐蚀速率随反应温度的升高而增大,在反应时间36 h,反应温度90℃和120℃下,腐蚀速率分别为0.382 mm/a和0.801 3 mm/a,属尚耐腐蚀;150℃和180℃下腐蚀速率分别为3.85 mm/a和6.01 mm/a,属不耐腐蚀。金相显微镜分析表明,316L不锈钢表面在较低温度的乳酸中以点蚀为主。现场挂片腐蚀实验结果表明,当温度低于120℃,316L可以作为乳酸生产设备的选材。

Corrosion properties of several metal materials in the lactic acid

The corrosion properties of 316L stainless steel,Ti,and Ni in lactic acid were studied by the weight loss method.The effects of reaction time and reaction temperature on corrosion of 316L stainless steel were investigated in detail.The results indicated that the corrosion rates of 316L in lactic acid were increased with increasing reaction temperature.When reaction time was 36 h,the corrosion rates of 316L stainless steel were 0.382 mm/a and 0.801 3 mm/a at 90 ℃ and 120 ℃ respectively and it had corrosion resistance.The corrosion rates were 3.85 mm/a and 6.01 mm/a at 150 ℃ and 180 ℃ respectively and it had low corrosion resistance.The metallurgical microscope photographs showed the corrosion of 316L stainless steel in lactic acid was pitting corrosion at low temperature.The results of coupon corrosion test were that 316L stainless steel might be used as materials for the production equipments of lactic acid when the temperature was lower than 120 ℃.