B的区别etween Anodic and Cathodic Protection

Thekey differencebetween anodic and cathodic protection is thatin anodic protection, the surface to be protected acts as the anode whereas, in cathodic protection, the surface to be protected acts as the cathode.

Anodic and cathodic protection are two electrochemical processes we use to prevent surfaces fromcorrosion or rusting. In an electrochemical process, we use an电化学细胞with two electrodes as anode and cathode. In anodic and cathodic protection processes, we use the surface to be protected (substrate) as either anode or cathode, which leads to name those processes as such. Sacrificial protection is a type of cathodic protection in which we use a metal as a sacrificial anode. In this process, this sacrificial metal corrodes while avoiding the corrosion of the cathode.

内容

1.Overview and Key Difference
2.什么是阳极保护
3.What is Cathodic Protection
4.Side by Side Comparison – Anodic vs Cathodic Protection in Tabular Form
5.概括

什么是阳极保护?

Anodic protection is a type of electrochemical process in which we can protect a metal surface by making it the anode in the electrochemical cell. We can denote this as AP. However, this method is possible only for material-environment combinations that show fairly wide passive regions. i.e.steel和不锈钢在98%硫酸。

在AP中，我们需要将金属带来高潜力。然后，由于保护层的形成，金属变得被动。但是，AP并未被广泛用作阴极保护，因为它仅限于表面上足够可靠的被动层的金属。例如，不锈钢。

There are two major considerations for the application of AP. First, we need to ensure that the whole system is in the passive range. Second, we need to have precise knowledge of ions, which can lead to extensive pitting.

What is Cathodic Protection?

Cathodic protection is a type of electrochemical process in which we can protect a metal surface by making it the cathode in the electrochemical cell. We can denote it as CP. CP can prevent metal surfaces from corrosion. There are different types of CP; for example, galvanic protection or sacrificial protection, impressed current systems and hybrid systems.

In this method, the sacrificial metal corrodes instead of the protected metal. If we use cathodic protection for large structures such as long pipelines, galvanic protection technique is not enough. Therefore, we need to provide sufficient current using an external DC electrical power source.

Moreover, we can use this technique to protect fuel or water pipelines made of steel, storage tanks, ships and boat hulls,galvanized steel, etc.

阳极和阴极保护有什么区别？

Anodic protection is a type of electrochemical process in which we can protect a metal surface by making it the anode in the electrochemical cell, while cathodic protection is a type of electrochemical process in which we can protect a metal surface by making it the cathode in the电化学细胞。So, the key difference between anodic and cathodic protection is that, in anodic protection, the surface to be protected acts as the anode whereas, in cathodic protection, it is the cathode.

此外，阳极保护涉及通过调节更具反应性金属的电势来抑制金属的反应性。但是，阴极保护涉及两个不同电极之间电流的流动。因此，我们也可以将其视为阳极和阴极保护之间的差异。

概括– Anodic vs Cathodic Protection

Anodic protection is a type of electrochemical process in which we can protect a metal surface by making it the anode in the electrochemical cell, while cathodic protection is a type of electrochemical process in which we can protect a metal surface by making it the cathode in the电化学细胞。阳极保护和阴极保护之间的主要区别在于，在阳极保护中，要保护的表面充当阳极，而在阴极保护中，它是阴极。

Reference:

1. “What Is a Sacrificial Protection? – Definition from Corrosionpedia.” Corrosionpedia,Available here.

Image Courtesy:

1. “Cathodic Protection diagram” By Cafe Nervosa – Own work(CC BY-SA 3.0)viaCommons Wikimedia
2. “Sacrificial anode” By Zwergelstern(CC BY-SA 3.0)viaCommons Wikimedia