Disadvantages Of Corrosion Essay

2.1 Introduction

This chapter gives a summary of the studies which are related to the subject matter and studies which are already present in literature. The primary aim of this chapter is to bring the risk associated with corrosion in the limelight and to better understand the different implications associated with the latter. This chapter is divided into two main parts;

• The first part gives an overview of the different forms of corrosion, its effect and control along with its different monitoring techniques.

• The second part deals with an introduction of the corrosion risk assessment process.

2.2 Corrosion

Corrosion is a naturally occurring phenomenon and can be defined in a number of ways. For instance, Fontana (1986) described this process as the

2.3 Forms of Corrosion

The corrosion process occurs widely in different forms. Its classification is usually determined by the following factors (ASM International, 2000):

• the corrodent’s nature;

• the mechanism of corrosion and;

• the appearance of the corroded metal. Figure 1: Common forms of Corrosion Source ASM 2000

Fontana (1986) characterised the different forms of corrosion depending on the way the metal manifests itself and the appearance of the corroded metal. A brief description of the basic forms of corrosion entails.

2.3.1 Uniform Corrosion

This form of corrosion is defined as the even deterioration of the surface of a metal, when exposed to a particular environment, without any appreciable localisation (NACE, 2015). It usually takes place when a metal or an alloy is subjected to a liquid, gaseous or hybrid electrolyte medium. The different types of general corrosion are listed below (Perez, 2004):

• Atmospheric corrosion

• Galvanic Corrosion

• High Temperature Corrosion

• Stray Current Corrosion

Table 1: Types of Uniform