Carbon steel plate: a basic building material treasure in the industrial field

In modern industry, carbon steel plate is an indispensable foundational material. Its excellent performance, wide applicability, and economical cost have made it ubiquitous in numerous fields, including construction, machinery, automobiles, and shipbuilding. Made from carbon steel through hot or cold rolling, it is a crucial product in the transformation of carbon steel and carries a vital role in driving industrial development.

I. Basic Concepts and Composition of Carbon Steel Plate

Carbon steel plate's core components are iron (Fe) and carbon (C). The carbon content is a key indicator that distinguishes its performance and classification. It also contains trace elements such as manganese (Mn), silicon (Si), sulfur (S), and phosphorus (P). Carbon steel itself is an iron-carbon alloy with a carbon content of less than 2.11%. Carbon steel plate is a flat sheet of steel with a specific thickness (typically 4-600mm) and width, processed from carbon steel billets through a rolling process. Depending on the rolling temperature, it can be divided into hot-rolled and cold-rolled carbon steel plates. Carbon plays a crucial role in steel plates: its carbon content directly affects their strength, hardness, and plasticity. Generally speaking, higher carbon content increases strength and hardness, but also reduces plasticity and toughness. Conversely, a lower carbon content improves plasticity and makes it easier to form.

II. Main Classifications of Carbon Steel Plates
Carbon steel plates can be divided into several categories based on various classification standards, the most common of which are based on carbon content and rolling process.

(I) Classification by Carbon Content

Low-carbon steel plates: Carbon content ≤ 0.25% exhibit excellent plasticity, toughness, and weldability, making them easy to form through cold working processes such as stamping and bending. They are commonly used in the manufacture of products requiring high formability and weldability, such as automobile bodies, agricultural machinery parts, containers, and pipes.

Medium-carbon steel plates: Carbon content ranges from 0.25% to 0.60%, offering moderate strength and hardness. While their plasticity is somewhat lower than that of low-carbon steel, they still possess reasonable processability. Mainly used in the manufacture of mechanical parts such as gears, shafts, connecting rods, and bolts. Some medium-carbon steel plates can be further enhanced in strength and toughness through quenching and tempering.

High-carbon steel plate: With a carbon content of ≥0.60%, it exhibits high strength, hardness, and wear resistance, but suffers from poor plasticity and toughness, and poor weldability. It is primarily used in the manufacture of products requiring high hardness and wear resistance, such as cutting tools, molds, springs, and rollers. Heat treatment (such as quenching and tempering) is typically required before use to optimize performance.

(II) Classification by Rolling Process

Hot-rolled carbon steel plate: Made from heated steel billets, hot-rolled carbon steel plate is rolled at high temperatures. Its advantages are high production efficiency and low cost. The steel plate has an oxide scale on the surface and relatively wide thickness tolerances, but it exhibits good toughness, making it suitable for the manufacture of large structural components, machinery bases, and bridge plates.

Cold-rolled carbon steel plate: Made from hot-rolled steel plate, cold-rolled at room temperature. After cold rolling, the steel plate achieves higher thickness precision, a smoother surface, and improved hardness and strength, but with reduced plasticity. It is commonly used in the manufacture of products requiring high surface quality and dimensional accuracy, such as automotive panels, appliance housings, and precision instrument parts.

III. Performance Characteristics of Carbon Steel Plate

The widespread industrial application of carbon steel plate is closely related to its unique performance characteristics:

Strength and Toughness Balance: By adjusting the carbon content and heat treatment process, strength and toughness can be flexibly matched to meet the needs of different applications. For example, the high toughness of low-carbon steel plate is suitable for withstanding impact loads, while the high strength of high-carbon steel plate is suitable for withstanding wear conditions.

Excellent Processability: Low-carbon steel plate is easily cold-worked (stamping, bending, and drawing) and welded, while medium-carbon steel plate can be machined into complex parts, facilitating product manufacturing.

Excellent Economic Performance: Carbon steel raw material reserves are abundant, and the production process is mature. Compared to materials such as stainless steel and alloy steel, carbon steel plate has a lower production cost, offering an extremely high cost-effectiveness, making it suitable for large-scale industrial applications. Highly Modifiable: Through processes such as heat treatment (quenching, tempering, normalizing, and annealing) and surface treatment (galvanizing, painting, and chrome plating), carbon steel plate's hardness, wear resistance, and corrosion resistance can be significantly improved, expanding its application range.

IV. Wide Application Areas of Carbon Steel Plate

As a fundamental industrial material, carbon steel plate is used in nearly every key sector of the national economy:

(I) Construction Engineering

In the construction industry, carbon steel plate is a core material for steel structures, used to manufacture load-bearing components such as beams, columns, and trusses. For example, large venues, high-rise buildings, and bridges often utilize hot-rolled low-carbon or medium-carbon steel plates for the main structure. Their high strength and stability ensure the safety and durability of the buildings. Furthermore, carbon steel plate is used to manufacture auxiliary components such as embedded parts, scaffolding, and steel sheet piles.

(II) Machinery Manufacturing

Machinery manufacturing is one of the primary applications of carbon steel plate. After tempering, medium-carbon steel plates can be used to manufacture key parts such as machine tool spindles, gears, and crankshafts. Low-carbon steel plates can be used to manufacture structural components such as machine tool casings and protective covers. High-carbon steel plates are used to manufacture high-wear parts such as machine tool cutting tools and molds. From ordinary agricultural machinery to heavy machinery, from general-purpose equipment to precision instruments, all rely on carbon steel plates.

(III) Automotive and Transportation Sector

In automotive manufacturing, carbon steel plates account for over 60% of all automotive steel. Cold-rolled low-carbon steel plates, due to their smooth surface and high dimensional accuracy, are commonly used to manufacture automotive body panels (doors, hoods, and trunk lids). Hot-rolled medium-carbon steel plates are used to manufacture load-bearing components such as vehicle frames, chassis, and drive shafts. High-carbon steel plates are used to manufacture parts such as automotive springs and clutch plates. Furthermore, carbon steel plates are also used extensively in the manufacture of transportation equipment such as train carriages, ship hulls, and containers. (IV) Petrochemical and Container Manufacturing

In the petrochemical industry, carbon steel plates are used to manufacture equipment such as pipelines, storage tanks, and reactors. Low-carbon steel plates, due to their excellent welding properties, are often made into large tanks and pipelines for storing and transporting media such as oil, natural gas, and chemical raw materials. Medium-carbon steel plates, after undergoing corrosion-resistant treatment, can be used to manufacture medium- and low-pressure reaction vessels, meeting the process requirements of chemical production.

(V) Other Industries

In addition to the aforementioned industries, carbon steel plates are also widely used in agricultural machinery manufacturing (tractor chassis, farm implement frames), household appliance manufacturing (refrigerator housings, washing machine drums), and hardware products (knives, kitchen utensils, and hardware accessories). They are an indispensable basic material in daily life and industrial production.​
V. Development Trends of Carbon Steel Plates

With the continuous advancement of industrial technology and increasing environmental protection requirements, the carbon steel plate industry is moving towards high-strength, lightweight, and green development:

High-strength: Through the development of microalloying technology and controlled rolling and cooling processes, the carbon content is reduced while the strength of the steel plate is increased. This achieves the goal of "thin instead of thick," reducing material usage and lowering structural weight. The use of high-strength carbon steel plates can effectively achieve lightweighting and reduce energy consumption, especially in areas such as automobiles and bridges.

Functional Upgrade: The development of carbon steel plates with specialized properties, such as weather-resistant carbon steel plates (to withstand harsh environments and reduce painting maintenance), wear-resistant carbon steel plates (for use in high-wear environments such as mining and construction machinery), and high-strength corrosion-resistant carbon steel plates (for use in marine engineering and chemical equipment), expands the scope of application.

Green Manufacturing: Optimizing production processes and promoting short-process steelmaking technology reduce energy consumption and carbon emissions during production. Strengthening the recycling of scrap carbon steel plates to increase resource recycling rates will drive the carbon steel plate industry towards a low-carbon and environmentally friendly direction.​
Conclusion
Carbon steel plate, a fundamental industrial material with a long history and a vibrant future, plays an irreplaceable role in the modern industrial system thanks to its flexible performance adjustment, wide applicability, and excellent cost-effectiveness. From skyscrapers to automobiles and ships, from precision machinery to daily necessities, carbon steel plate is ubiquitous. With continuous technological innovation, carbon steel plate will continue to develop towards higher performance, greater environmental friendliness, and greater efficiency, contributing even more to promoting industrial progress and economic development.