As an important engineering material, stainless steel fasteners have been widely used in various industries and fields. Especially in the fields of chemical, petroleum, pharmaceutical and Marine engineering, stainless steel fasteners often need to be exposed to corrosive environments such as acid and alkali. In this case, corrosion resistance has become one of the important indicators to evaluate the advantages and disadvantages of fasteners. This paper will discuss the corrosion resistance of stainless steel fasteners in acid and alkali environment, introduce the relevant research status, application and further research problems.
First, research status of corrosion resistance of stainless steel fasteners
The corrosion resistance of stainless steel fasteners is related to the materials selected, the surface state and environmental factors. In general, austenitic stainless steel (such as 304, 316L and 321, etc.) has good corrosion resistance in acid and alkali environments. The corrosion resistance of martensitic stainless steel (such as 410, 420, etc.) is relatively poor.
The corrosion resistance of different types of stainless steel fasteners in acid and alkali environments varies greatly. In an acidic environment, 304 stainless steel has better corrosion resistance, while 316L stainless steel has better corrosion resistance in a high-temperature acidic environment. In an alkaline environment, 316L stainless steel has better corrosion resistance, while 304 stainless steel is prone to stress corrosion cracking in an alkaline environment containing chloride ions.
The corrosion resistance of stainless steel fasteners is also affected by the surface state. In a corrosive environment, the surface of the fastener will rust, and the surface treatment can effectively improve the corrosion resistance of the fastener. For example, surface treatment methods such as zinc plating, chrome plating, and epoxy coating can increase the corrosion resistance of fasteners.
Second, the application of stainless steel fasteners in acid and alkali environment
Stainless steel fasteners are widely used in acid and alkali environments. For example, in industrial installations, stainless steel fasteners can be used to secure critical parts such as chemical equipment, pressure vessels and pipes to ensure the safe operation of equipment in corrosive environments. In shipbuilding, stainless steel fasteners can be used in key parts such as hull structure, deck and cabin to improve the corrosion resistance and service life of the ship. In the field of construction, stainless steel fasteners can be used to fix various materials, such as concrete, wood and stone, so that the safety of buildings in corrosive environments is guaranteed.
In these applications, stainless steel fasteners need to meet the appropriate standards and specifications. For example, in the chemical industry, stainless steel fasteners need to meet the requirements of HG/T 20582-2011 “Steel chemical container Material Selection Regulations” and other relevant standards. In the shipbuilding industry, stainless steel fasteners need to meet the regulations and requirements of relevant institutions such as China Classification Society (CCS). In the field of construction, stainless steel fasteners need to meet the requirements of relevant standards and specifications such as JGJ 144-2014 “Technical Regulations for Waterproof Engineering of Building External Walls”.
Stainless steel fasteners have a wide range of application prospects in acid-alkali environment. However, it exhibits different corrosion resistance in different types and environments, so it is necessary to choose the appropriate material and surface treatment method according to the specific application scenario. At the same time, in order to better guide the practical application, it is necessary to further study the corrosion resistance and influencing factors of stainless steel fasteners, and improve the corresponding standards and specifications.
