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DC Supply;Aluminium Anode;Lead Cathode;Sulphuric Acid;Electr

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DC Supply;Aluminium Anode;Lead Cathode;Sulphuric Acid;Electrolyte
Figure 1:Electrolysis Setup of Anodized Aluminum
Analysis of metals under different process modification such as anodization (whether chemical; electrolyte,or electrical input) impart distinct microstructural changes to the anodic film when compared to the microstructures of anodic films formed through other means.16,17,18,19
EXPERIMENTAL PROCEDURE
Materials and Equipment
Aluminum Alloy 5052 with chemical composition shown in Table 1 was used for the laboratory experiment.Other materials used include sulphuric acid of 98% purity,washing detergents,distilled water,tissue papers,caustic soda,and thermoplastic resin,abrasive paper,etching reagent and alumina powder.The equipment used include beaker,conical flasks,laboratory mercury thermometer,scissor,(lead),digital weighing balance,car batteries,hack saw,coarse file,Rockwell (indented hardness testing machine and metallurgical microscope.The electrolyte used for this experiment,was prepared from sulphuric acid of 98% purity,1.84 specific gravity and 98.08 molecular weight.
Molarity (mol/dm3) = 1000 x specific gravity x percentage purity / molecular weight (1)
i.e molar concentration (molarity) = 1000 x 1.84 x 98% / 98.08
= 18.4mol/dm3 (standard concentration)
From the expression above,the solutions of 15%,20%,30%,40% and 50% by volume of the acid were prepared.
Procedure
The aluminum substrate was first washed and cleaned thoroughly to remove oils,grease and scales,before it was anodized.The sequence of the anodization process and examination of the microstructure carried out according to.5,14 The aluminum sample was dipped in hot tank containing alkaline solution to remove all surface dirt then rinsed to avoid contaminating the solution in subsequent tasks.The sample was dipped again in sulphuric acid at room temperature for about 3 seconds and then rinsed again in distilled water.Etching was performed by suspending the part in a beaker containing sodium hydroxide solution for about 10 seconds.The etching done removed the shine of the aluminum and provided a soft,texture appearance.
Thereafter,the aluminum sample and lead were suspended in the beaker.The wire from the aluminum and lead were connected to two car batteries of 12V each,capable of producing DC power of 24v of electricity to complete the electrical connection.The electrical cell was complete with the aluminum piece as positive anode and lead as negative cathode.
Anodization was then allowed to take place after completing the electrical circuit at room temperature and for a constant time of 30 minutes for each sample.At the end of the experiment,the aluminum sample was then rinsed in distilled water and then finally dried and the weighing was done after 45 seconds.The metallographic examination was then carried out according to.8,9,15
图1:铝阳极氧化膜电解的设置
  分析在不同加工的金属氧化修饰(无论是化工;电解质、或电气输入)传授不同微观结构的变化对阳极氧化膜相比,氧化膜微观结构形成通过其他的方法.16、17、18、19   
实验过程 
材料和设备 
 铝合金5052年,化学成分显示在表1是用于实验室实验.使用的其他资料包括硫酸98%纯度、洗涤用品,蒸馏水、组织论文、离子膜烧碱、热塑性树脂、磨料纸、蚀刻剂和氧化铝粉末.设备使用包括烧杯、锥形瓶、实验室水银温度计、剪下来,(铅)、数字重平衡、汽车电池,黑客锯、粗糙的文件、洛(锯齿状的硬度试验机、金相显微镜.电解液用于这个实验,从硫酸法制备了98%的纯度,比重1.84和98.08分子量等.  摩尔浓度(水解/ dm3)= 1000××百分比比重纯度/分子量(1)   摩尔浓度(摩尔浓度如下料和设备)
从表达上述的解分别为15%、20%、30%、40%和50%(体积比)混合酸的准备.  
程序
  铝基体首次清洗干净彻底去除油、油脂和规模、阳极氧化之前.氧化过程的顺序和考试的微观结构进行了根据.五、14铝样品是蘸坦克含碱性溶液去除肌肤表面污垢然后冲洗避免污染解决在随后的任务.样品又在硫酸浸在室温大约3秒钟,然后又在蒸馏水清洗.蚀刻进行暂停参加一个烧杯的氢氧化钠溶液含有大约10秒.蚀刻做删除一条闪闪发光的铝,并提供了一个柔软、纹理出现.
此后,铝样品和铅被中断烧杯里.这条电线的铝铅连接了两辆汽车电池12 V的每一个,能生产24 V直流电源的电力来完成电气连接.电气细胞块完整的铝阳极和积极引导是负面的阴极.