​What gauge is a 1mm gi sheet?

1mm gi sheet is made of cold-rolled or hot-rolled steel plate as the base material, and the surface is covered with a layer of zinc layer with a thickness of about 1mm through hot-dip galvanizing process. Its core specifications cover four dimensions: thickness, width, length, and zinc layer quality. It not only meets the basic anti-corrosion requirements, but also adapts to various fields such as construction, home appliances, and automobiles through standardized parameters. In terms of thickness, the standard specification is 1.0 ± 0.05mm to ensure structural strength and processing stability; The width is commonly 1000mm, 1200mm, 1250mm, 1500mm, and can be customized up to 1800mm; the length is mainly 2000mm, 2500mm, and 3000mm, and can be cut as needed. The quality of the zinc layer is classified according to national standards as Z80 (80g/m ²), Z120 (120g/m ²), etc., which directly affects corrosion resistance. For example, Z120 or higher specifications are required for high humidity coastal environments. The following will provide a detailed introduction to the specifications of 1mm gi sheet sheet.

1. Basic Definition and Classification

Gi sheet refers to a steel plate with a layer of zinc coating on its surface. This layer of zinc is like a protective film, which can effectively prevent the steel plate from rusting and corroding, greatly extending the service life of the steel plate. According to different processing techniques, gi sheets are mainly divided into two categories: hot-dip gi sheets and electroplated gi sheets.
Hot dip gi sheet sheet is a process of immersing rust removed steel components in a molten zinc solution at around 500 ℃ to attach a zinc layer to the surface of the steel components, thereby achieving the purpose of corrosion prevention. The zinc layer formed by this process is relatively thick, usually over tens of microns, with good corrosion resistance and adhesion, suitable for outdoor environments with high anti-corrosion requirements, such as building exterior walls, highway guardrails, etc.

Electroplated gi sheets are coated with a thin layer of zinc through electrolysis. The thickness of its zinc layer is generally between a few micrometers and a dozen micrometers, and its appearance is relatively bright, but its corrosion resistance is slightly weaker compared to hot-dip gi sheets. Electroplated gi sheet sheet is commonly used in applications that require high surface quality and relatively mild corrosive environments, such as household electrical enclosures and indoor decoration. 1mm gi sheet is also produced according to these two processes to meet the needs of different users.

2. Size specifications

1. Thickness
One of the core specifications of 1mm gi sheet is a thickness of 1mm. This thickness achieves a good balance between performance and cost in many applications. In some situations where structural strength is not extremely high but certain corrosion resistance is required, such as indoor lightweight partitions, ventilation ducts, etc., a thickness of 1mm can ensure sufficient strength without increasing unnecessary costs and weight due to excessive material thickness.
2. Width and length
The width and length specifications of 1mm gi sheet are relatively diverse to meet the needs of different projects. Common width specifications include 1000mm, 1200mm, 1250mm, etc., and length can be customized according to order requirements, generally between 2000mm-6000mm. For example, in the field of architecture, for some small roof construction projects, a 1mm gi sheet with a width of 1000mm and a length of about 3000mm may be chosen; In the construction of large industrial plants, in order to reduce splicing and improve construction efficiency, specifications with a width of 1250mm and a length of 6000mm may be used.

Table: Common 1mm gi sheet size specifications

Width (mm)	Common Length (mm)	Suitable Scenarios
1000	2000 - 4000	Indoor lightweight partitions, small ventilation ducts
1200	2500 - 5000	General building roofs, walls of small warehouses
1250	3000 - 6000	Roofs and walls of large industrial factories

3. Zinc layer specification

The thickness of the zinc layer is one of the important indicators for measuring the quality of gi sheets. For 1mm gi sheets, the thickness of the zinc layer may vary depending on different usage environments and standard requirements. Generally speaking, the zinc layer thickness of hot-dip galvanized 1mm steel plate can reach 50 μ m-100 μ m or more, providing long-term anti-corrosion protection. In some coastal areas or highly polluted environments, products with thicker zinc layers are chosen to ensure the corrosion resistance of steel plates. The zinc layer thickness of 1mm gi sheet is relatively thin, usually between 5 μ m-15 μ m, which is suitable for indoor and other less corrosive environments.

4. Mechanical performance specifications

1. Yield strength
Yield strength is a measure of the stress at which a material begins to undergo significant plastic deformation. The yield strength of 1mm gi sheet varies depending on the material and production process. The common 1mm gi sheet made of ordinary carbon structural steel generally has a yield strength of around 235MPa. This means that when subjected to stress not exceeding 235 MPa, the steel plate can maintain elastic deformation without significant plastic deformation. In some applications that require high strength, such as automobile manufacturing and high-end building structures, 1mm gi sheets made of high-strength steel are used, with a yield strength of up to 345MPa or even higher.
2. Tensile strength
Tensile strength refers to the maximum stress that a material can withstand before being pulled apart. The tensile strength and yield strength of 1mm gi sheet are closely related. Generally speaking, the tensile strength of products made of ordinary carbon structural steel is between 375MPa-500MPa. The tensile strength of 1mm gi sheet made of high-strength steel is higher, which can meet more complex stress conditions.
3. Elongation rate

Elongation is an important indicator for measuring the plasticity of materials, which reflects the deformation ability of materials before fracture. The elongation rate of 1mm gi sheet is usually between 15% and 30%. A higher elongation rate means that the steel plate can better absorb energy under stress, is less prone to brittle fracture, and has good adaptability in some situations that require dynamic or impact loads, such as bridges, mechanical equipment, etc.

5. Surface quality specifications

The surface quality of 1mm gi sheet has a significant impact on its appearance and performance. The surface of high-quality gi sheet should be smooth and even, without obvious defects such as zinc nodules, burrs, scratches, etc. The zinc layer should be uniformly adhered to the surface of the steel plate without any missed plating, peeling, or other phenomena. When observed under light, the surface of the steel plate should have a certain glossiness, reflecting good galvanizing quality. In addition, for some applications with special requirements, such as food processing equipment, pharmaceutical manufacturing, etc., there are strict requirements for the surface cleanliness and hygiene of gi sheets, which require the use of special production processes and surface treatment technologies to meet them.

As a basic material in the industrial field, 1mm gi sheet has a specification design that accurately matches the dual needs of practicality and economy. The tolerance control of thickness 1.0 ± 0.05mm ensures stability during processing; Standardized dimensions with a width of 1000-1500mm, balancing transportation efficiency and flexibility in use; The customized length feature further enhances material utilization.