论文部分内容阅读
本工作利用KCl-Ag/AgCl微参比电极和钨微电极研究了在试样预裂纹顶部应力集中的微小区域里,应力对1Cr18Ni9Ti不锈钢在3.5％NaCl溶液中电化学及化学状态(溶液酸度)的影响。研究表明,在应力腐蚀过程中,微区的电化学和化学状态与应力的存在有关。在发生塑性变形的条件下,应力他材料发生滑移,导致表面钝化膜的破坏,使微区电位下降,每次施加应力均使微区电位突降约40毫伏,当再钝化过程受阻,裂纹开始形成时,由于金属的大量溶解,使这里的pH值迅速下降到1～2之间,造成裂纹形成时它周围的低电化、低pH环境。
In this work, the electrochemical and chemical state (solution acidity) of 1Cr18Ni9Ti stainless steel in 3.5% NaCl solution was studied in the tiny area with the stress concentration at the top of the pre-cracked specimen by using KCl-Ag / AgCl micro reference electrode and tungsten microelectrode. Impact. Studies have shown that in the stress corrosion process, the micro-electrochemical and chemical state and the existence of stress. Under the condition of plastic deformation, the stress of his material slippage, resulting in the destruction of the surface passivation film, the micro-area potential decreased, each application of stress so that the micro-area potential dip about 40 millivolts, when the passivation process When the crack begins to form, the pH value here rapidly drops to between 1 and 2 due to the large amount of metal dissolved, resulting in a low-electric and low-pH environment around the crack when it is formed.