al18b4o33wal复合材料表面电沉积ni p合金的耐蚀性研究word格式论文.docxVIP

摘 要电沉积法通常称电镀，可以在相对简单的条件下获得晶粒尺寸为 1～ 100nm的各种纳米晶体材料，是一种通过外加电源使电流经阴极、电解液、 阳极，在阴极表面还原金属的方法。本文利用电沉积方法在Al18B4O33w/Al 复合材料基体表面制备Ni-P合金。通过SEM、TEM和XRD观察分析材料表面形貌、组织结构的影响，结 果表明：随着电流密度的增大及镀液pH值的升高，电沉积Ni-P合金镀层的 厚度逐渐增大，各镀层与Al18B4O33w/Al复合材料基底均有良好的结合；当 沉积电流密度为 2000A/m2 ，镀液pH值为 2，电镀时间为 3h时，电沉积Ni-P 合金镀层的表面最为平整，非晶态程度最大。表面观察不到气孔、瘤状物等 缺陷的存在；随着电沉积时间的延长，Ni-P合金镀层表面的致密度不断提 高，Ni-P合金镀层的厚度也不断增大，同时非晶态程度也不断增加；Ni-P率 先在Al18B4O33w/Al复合材料中晶须与基体的界面上沉积，而且在这些区域 的沉积速率较快。动态极化曲线测试表明：随着电沉积时间的延长，Ni-P 合金镀层的耐 腐蚀性能不断增加。电化学阻抗谱(EIS)表明： Ni-P 合金镀层本身具有较高的耐蚀能力，在 NaCl 溶液中浸泡初期，镀层自身存在自修复过程，Nyquist 图中的圆弧直径 随浸泡时间的增加而不断增大，随后呈下降趋势。热处理试验表明：经 200℃与 400℃退火热处理以后镀层表面出现不同 程度的晶态组织，两种热处理温度对镀层表面晶化程度的影响显著不同。从 而导致其耐腐蚀性明显不同；经 400℃退火热处理使得镀层的耐腐蚀性能下 降得更为显著。关键词电沉积；Ni-P 合金；腐蚀；热处理AbstractGenerally, electrodeposition which is also called electrophoretic coating, can achieve all kinds of nanocrystal materials whit size of 1~100nm under certain simple conditions. It is a method that deacidize the metal on the catelectrode surface, applying a external voltage makes the current flows through the catelectrode, electrolyte, electrode. In this paper, the preparation of Ni-P alloy is based on the electrodeposition on the surface of Al18B4O33w/Al composite.By the analyzing to the pattern of the surface and the histology of thematerial, through SEM, TEM and XRD, we get the consequence that: the thickness of the plating Ni-P film is thickening when the current density and pH are raising. Each film has a good bonding with the composite basis; In the condition of current density is 2000A/m2, pH reaches 2 and the time of plating is 3h, the surface of the plating Ni-P film is the smoothest, it also has the biggest amorphous state. No observation of blow holes and objects in nodular form; Enlarging the plating time, the density and the amorphous degree of the surface of plating Ni-P film are all better, the thickness is thickening, too; Ni-P gets a better plating speed and firstly deposits on the area of the interface between the whiskers and