Material Introduction

　　Steel: Steel is a material made into various shapes, sizes, and properties as needed through pressure processing of steel ingots, billets, or steel. Steel is an indispensable important material for national construction and the realization of the four modernizations. It has wide applications and numerous varieties. According to the different cross-sectional shapes, steel is generally divided into four major categories: profiles, plates, pipes, and metal products, which are further divided into heavy rails, light rails, large-section steel, medium-section steel, small-section steel, cold-bent steel, high-quality steel, wire rods, medium and thick steel plates, thin steel plates, silicon steel sheets for electrical use, strip steel, seamless steel pipes, welded steel pipes, and metal products, etc.

　　Characteristics

　　Ferrous Metals: Ferrous metals mainly refer to iron, manganese, chromium and their alloys.

　　Steelmaking: Steel is obtained by smelting pig iron used for steelmaking in a steelmaking furnace according to a certain process.

　　Non-ferrous Metals: Metals other than ferrous metals are called non-ferrous metals, such as copper, tin, lead, zinc, aluminum, as well as brass, bronze, aluminum alloys and bearing alloys, etc.

　　Relevant Terms

　　Carbon Steel: Carbon steel, also called carbon steel, is an iron-carbon alloy with a carbon content (wc) of less than 2%. In addition to carbon, carbon steel generally contains small amounts of silicon, manganese, sulfur, and phosphorus. According to its purpose, carbon steel can be divided into three categories: carbon structural steel, carbon tool steel, and free-cutting structural steel. Carbon structural steel can be further divided into two types: structural steel for buildings and structural steel for machinery manufacturing. According to the carbon content, carbon steel can be divided into low-carbon steel (wc≤0.25%), medium-carbon steel (wc 0.25%~0.6%) and high-carbon steel (wc>0.6%). According to the phosphorus and sulfur content, carbon steel can be divided into ordinary carbon steel (higher phosphorus and sulfur content), high-quality carbon steel (lower phosphorus and sulfur content) and high-grade high-quality steel (even lower phosphorus and sulfur content). In general carbon steel, the higher the carbon content, the higher the hardness and strength, but the lower the plasticity.

　　Carbon Structural Steel: This type of steel mainly ensures mechanical properties; therefore, its grade reflects its mechanical properties, represented by Q + number, where "Q" is the first letter of the pinyin of the Chinese character for "yield point" (屈), and the number represents the yield point value. For example, Q275 indicates a yield point of 275 MPa. If the grade is marked with letters A, B, C, D, it indicates different steel quality grades, with the amounts of S and P decreasing successively and the steel quality increasing successively. If the letter "F" is marked after the grade, it is boiling steel; if "b" is marked, it is semi-killed steel; if neither "F" nor "b" is marked, it is killed steel. For example, Q235-A·F represents grade A boiling steel with a yield point of 235 MPa, and Q235-c represents grade C killed steel with a yield point of 235 MPa. Carbon structural steel is generally not heat-treated and is used directly in the supply state. Generally, Q195, Q215, and Q235 steels have low carbon mass fractions, good weldability, good plasticity and toughness, and certain strength. They are often rolled into thin plates, reinforcing bars, welded steel pipes, etc., and used in bridge and building structures and for manufacturing ordinary rivets, screws, nuts, and other parts. Q255 and Q275 steels have slightly higher carbon mass fractions, higher strength, and good plasticity and toughness. They can be welded and are usually rolled into steel profiles, bars, and steel plates for structural parts and for manufacturing connecting rods, gears, couplings, pins, and other parts of simple machinery.

　　High-quality Structural Steel: This type of steel must ensure both chemical composition and mechanical properties. Its grade uses two digits to represent the ten thousandth of the average carbon mass fraction (wс × 10000) in the steel. For example, 45 steel indicates that the average carbon mass fraction in the steel is 0.45%; 08 steel indicates that the average carbon mass fraction in the steel is 0.08%. High-quality carbon structural steel is mainly used for manufacturing machine parts. It generally needs to undergo heat treatment to improve its mechanical properties. Different applications exist based on different carbon mass fractions. 08, 08F, 10, and 10F steels have high plasticity and toughness, excellent cold forming and welding properties, and are often cold-rolled into thin plates, used for making instrument casings and cold-pressed parts on automobiles and tractors, such as car bodies and tractor cabs; 15, 20, and 25 steels are used for making smaller parts with lighter loads, wear-resistant surfaces, and low core strength requirements for carburizing parts such as piston pins and templates; 30, 35, 40, 45, and 50 steels, after heat treatment (quenching + high-temperature tempering), have good comprehensive mechanical properties, namely higher strength and higher plasticity and toughness, used for manufacturing shaft parts. For example, 40 and 45 steels are often used to manufacture crankshafts, connecting rods of automobiles and tractors, main spindles of general machine tools, machine tool gears, and other shaft parts with less stress; 55, 60, and 65 steels, after heat treatment (quenching + medium-temperature tempering), have a high elastic limit and are often used for manufacturing springs with small loads and sizes (cross-sectional dimensions less than 12-15 mm), such as pressure and speed regulating springs, plunger springs, and cold-wound springs.

　　Carbon Tool Steel: Carbon tool steel is a high-carbon steel that is essentially free of alloying elements, with a carbon content in the range of 0.65% to 1.35%. It has low production costs, readily available raw materials, good machinability, and after treatment, it can achieve high hardness and high wear resistance, so it is a widely used steel grade, used to manufacture various cutting tools, molds, and measuring tools. However, this type of steel has poor red hardness, that is, when the working temperature is greater than 250 ℃, the hardness and wear resistance of the steel will drop sharply, losing its working ability. In addition, if carbon tool steel is made into larger parts, it is difficult to harden and is prone to deformation and cracks.

　　Free-cutting Structural Steel: Free-cutting structural steel adds some elements that make the steel brittle to the steel, making the chips easy to break into fragments during cutting, thereby improving the cutting speed and extending the tool life. The elements that make the steel brittle are mainly sulfur, and lead, tellurium, and bismuth are used in ordinary low-alloy free-cutting structural steel. The sulfur content ws of this type of steel is in the range of 0.08% to 0.30%, and the manganese content wMn is in the range of 0.60% to 1.55%. The sulfur and manganese in the steel exist in the form of manganese sulfide, which is very brittle and has lubricating properties, making the chips easy to break and improving the quality of the processed surface.

　　Alloy steel, in addition to iron, carbon, and small amounts of unavoidable silicon, manganese, phosphorus, and sulfur, also contains a certain amount of alloying elements. The alloying elements in steel include one or more of silicon, manganese, molybdenum, nickel, chromium, vanadium, titanium, niobium, boron, lead, and rare earth elements. This type of steel is called alloy steel. Alloy steel systems in different countries vary depending on their respective resource conditions, production, and usage. Foreign countries previously developed nickel-chromium steel systems, while China developed alloy steel systems mainly based on silicon, manganese, vanadium, titanium, niobium, boron, and rare earth elements. Alloy steel accounts for about 10% of the total steel output and is generally smelted in electric furnaces. According to its use, alloy steel can be divided into eight categories: alloy structural steel, spring steel, bearing steel, alloy tool steel, high-speed tool steel, stainless steel, heat-resistant scaling-resistant steel, and electrical silicon steel.

　　Ordinary low-alloy steel is a common alloy steel containing a small amount of alloying elements (in most cases, the total amount w does not exceed 3%). This steel has relatively high strength, good comprehensive performance, and exhibits corrosion resistance, wear resistance, low-temperature resistance, as well as good machinability and weldability. Under the condition of saving scarce alloying elements (such as nickel and chromium), 1 ton of ordinary low-alloy steel can typically replace 1.2-1.3 tons of carbon steel, with a much longer service life and wider application range. Ordinary low-alloy steel can be smelted using general smelting methods in open-hearth furnaces and converters, and its cost is also close to that of carbon steel.

　　This refers to alloy steel used in engineering and building structures, including weldable high-strength alloy structural steel, alloy reinforcing steel, railway alloy steel, alloy steel for geological and petroleum exploration, alloy steel for pressure vessels, and high-manganese wear-resistant steel. This type of steel is used for engineering and building structural components. Among alloy steels, this type has a relatively low total alloy content but a large production and usage volume.

　　This type of steel refers to alloy steel suitable for manufacturing machines and mechanical parts. It is based on high-quality carbon steel, with the addition of one or more alloying elements to improve the strength, toughness, and hardenability of the steel. This type of steel usually needs to undergo heat treatment (such as tempering, surface hardening) before use. It mainly includes commonly used alloy structural steel and alloy spring steel, including tempered alloy steel, surface-hardened alloy steel (carburizing steel, nitriding steel, surface high-frequency quenching steel, etc.), and alloy steel for cold plastic forming (steel for cold heading, steel for cold extrusion, etc.). According to the basic chemical composition series, it can be divided into Mn series steel, SiMn series steel, Cr series steel, CrMo series steel, CrNiMo series steel, Nj series steel, B series steel, etc.

　　The carbon content wc of alloy structural steel is lower than that of carbon structural steel, generally in the range of 0.15%-0.50%. In addition to carbon, it also contains one or more alloying elements, such as silicon, manganese, vanadium, titanium, boron, nickel, chromium, and molybdenum. Alloy structural steel is easy to harden and is not prone to deformation or cracking, making it suitable for heat treatment to improve steel properties. Alloy structural steel is widely used in the manufacture of various transmission parts and fasteners for automobiles, tractors, ships, steam turbines, and heavy machine tools. Low-carbon alloy steel is generally carburized, while medium-carbon alloy steel is generally tempered.

　　Alloy tool steel is medium- or high-carbon steel containing various alloying elements such as silicon, chromium, tungsten, molybdenum, and vanadium. Alloy tool steel is easy to harden and is not prone to deformation or cracking, making it suitable for manufacturing large-sized, complex-shaped cutting tools, molds, and gauges. The carbon content of alloy tool steel varies depending on its application. Most alloy tool steels have a carbon content wc of 0.5%-1.5%. Steel for hot deformation molds has a lower carbon content, wc in the range of 0.3%-0.6%; steel for cutting tools generally has a carbon content wc of around 1%; and steel for cold working molds has a higher carbon content, such as graphite mold steel with a carbon content wc of 1.5%, and high-carbon, high-chromium cold-working mold steel with a carbon content wc of over 2%.

　　High-speed tool steel is high-carbon, high-alloy tool steel. The steel contains 0.7%-1.4% carbon (wc) and alloying elements that can form high-hardness carbides, such as tungsten, molybdenum, chromium, and vanadium. High-speed tool steel has high red hardness; even at high-speed cutting temperatures of 500-600 degrees Celsius, its hardness does not decrease, ensuring good cutting performance.

　　Springs are used under impact, vibration, or long-term alternating stress, so spring steel is required to have high tensile strength, elastic limit, and high fatigue strength. In terms of process requirements, spring steel must have a certain hardenability, be resistant to decarburization, and have good surface quality. Carbon spring steel is high-quality carbon structural steel (including normal and higher manganese content) with a carbon content wc in the range of 0.6%-0.9%. Alloy spring steel is mainly silicon-manganese steel, with slightly lower carbon content, mainly relying on increasing silicon content WSi (1.3%-2.8%) to improve performance; there are also chromium, tungsten, and vanadium alloy spring steels. Combining China's resources and the requirements of new technologies in automobile and tractor design, new steel types have been developed by adding boron, niobium, and molybdenum to silicon-manganese steel, extending the service life of springs and improving spring quality.

　　Bearing steel is used to manufacture ball bearings, rollers, and bearing rings. Bearings are subjected to extremely high pressure and friction during operation, so bearing steel is required to have high and uniform hardness and wear resistance, as well as a high elastic limit. The uniformity of the chemical composition of bearing steel, the content and distribution of non-metallic inclusions, and the distribution of carbides are all strictly controlled. Bearing steel, also known as high-carbon chromium steel, contains about 1% carbon (wc) and 0.5%-1.65% chromium (wc). Bearing steel is divided into six categories: high-carbon chromium bearing steel, chromium-free bearing steel, carburized bearing steel, stainless bearing steel, medium-high temperature bearing steel, and anti-magnetic bearing steel.

　　Electrical silicon steel is mainly used to manufacture silicon steel sheets for the electrical industry. Silicon steel sheets are widely used in the manufacture of motors and transformers. According to the chemical composition, silicon steel can be divided into low silicon steel and high silicon steel. Low silicon steel contains 1.0%-2.5% silicon (wSi), mainly used for motor manufacturing; high silicon steel contains 3.0%-4.5% silicon (wSi), generally used for transformer manufacturing. Their carbon content wc ≤ 0.06%-0.08%.

　　Rail steelRail steel primarily bears the pressure and impact load of locomotives and rolling stock; therefore, it requires sufficient strength and hardness, as well as a certain degree of toughness. Generally, the rail steel used is carbon-killed steel smelted in open-hearth or converter furnaces. This steel contains 0.6%~0.8% carbon (Wc), making it a medium or high carbon steel. However, it contains a higher manganese content (WMn) ranging from 0.6% to 1.1%. Ordinary low-alloy steel rails, such as high-silicon rails, medium-manganese rails, copper-containing rails, and titanium-containing rails, have been widely adopted. Ordinary low-alloy steel rails are more wear-resistant and corrosion-resistant than carbon steel rails, significantly improving service life.

　　Steel for shipbuildingSteel for shipbuilding refers to steel used to manufacture the hull structures of seagoing vessels and large inland river vessels. Since ship hull structures are generally manufactured using welding methods, the shipbuilding steel is required to have good weldability. In addition, it must possess a certain degree of strength, toughness, and low-temperature and corrosion resistance. In the past, low-carbon steel was mainly used as shipbuilding steel. A large quantity of ordinary low-alloy steel is now used, including steel types such as 12Mn ship steel, 16Mn ship steel, and 15MnV ship steel. These steel types exhibit high strength, good toughness, easy processing and welding, and resistance to seawater corrosion. They have been successfully used in manufacturing large ocean-going vessels.

　　Steel for bridgesRailway or highway bridges bear the impact load of vehicles. The steel for bridges requires a certain degree of strength, toughness, good fatigue resistance, and high surface quality. Basic open-hearth killed steel is often used for bridge steel, and ordinary low-alloy steels such as 16Mn and 15MnVN have been successfully used.

　　Boiler steelBoiler steel mainly refers to the materials used to manufacture superheaters, main steam pipes, and the heat-receiving surfaces of boiler furnaces. The performance requirements for boiler steel primarily include good weldability, certain high-temperature strength, and resistance to alkaline corrosion and oxidation. Commonly used boiler steels include low-carbon killed steel smelted in open-hearth furnaces or low-carbon steel smelted in electric furnaces, with a carbon content (Wc) ranging from 0.16% to 0.26%. Pearlitic heat-resistant steel or austenitic heat-resistant steel is used to manufacture high-pressure boilers. Ordinary low-alloy steels such as 12Mn, 15MnV, and 18MnMoNb are also used in boiler construction.

　　Steel for welding rodsThis type of steel is specifically used for manufacturing welding rods and wires for arc welding and gas welding. The composition of the steel varies depending on the material being welded. Based on the needs, it is broadly divided into three categories: carbon steel, alloy structural steel, and stainless steel. The sulfur and phosphorus content (Ws, WP) of these steels is no more than 0.03%, stricter than that of general steel. These steels do not require mechanical property testing but only chemical composition testing.

　　Stainless steelStainless and acid-resistant steel is referred to as stainless steel. It consists of two main parts: stainless steel and acid-resistant steel. In short, steel that can resist atmospheric corrosion is called stainless steel, while steel that can resist chemical corrosion (such as acids) is called acid-resistant steel. Generally, steel with a chromium content (Wcr) greater than 12% exhibits the characteristics of stainless steel. According to the microstructure after heat treatment, stainless steel can be further divided into five categories: ferritic stainless steel, martensitic stainless steel, austenitic stainless steel, austenitic-ferritic stainless steel, and precipitation-hardened stainless steel.

　　Heat-resistant steelSteel that possesses oxidation resistance, sufficient high-temperature strength, and good heat resistance under high-temperature conditions is called heat-resistant steel. Heat-resistant steel includes oxidation-resistant steel and heat-resistant steel. Oxidation-resistant steel is also known as scaling-resistant steel. Heat-resistant steel refers to steel that has good oxidation resistance and high high-temperature strength at high temperatures. Heat-resistant steel is mainly used for parts that are used for extended periods at high temperatures.

　　High-temperature alloyHigh-temperature alloy is a heat-resistant material that possesses sufficient creep strength, thermal fatigue strength, high-temperature toughness, and sufficient chemical stability at high temperatures. It is used for thermal power components operating under high-temperature conditions above 600 degrees Celsius. According to their basic chemical composition, they can be further divided into nickel-based high-temperature alloys, iron-nickel-based high-temperature alloys, and cobalt-based high-temperature alloys.

　　Precision alloyPrecision alloys are alloys with special physical properties. They are indispensable materials in the electrical industry, electronics industry, precision instrument industry, and automatic control systems. Precision alloys are divided into seven categories according to their different physical properties: soft magnetic alloys, deformable permanent magnetic alloys, elastic alloys, expansion alloys, thermal bimetals, resistance alloys, and thermocouple alloys. The vast majority of precision alloys are based on ferrous metals, with only a few based on non-ferrous metals. Note: Wc, Ws, Wmn, and Wp represent the mass fractions of C, S, Mn, and P, respectively.

　　Common Terminology

　　1. Standards: Standards are unified regulations for repetitive things and concepts. They are based on the comprehensive achievements of science, technology, and practical experience, agreed upon by relevant parties, approved by the competent authority, and released in a specific form as a common rule and basis for compliance. The standards implemented for steel products in China include national standards (GB, GB/T), industry standards (YB), local standards, and enterprise standards. 2. Technical Conditions: The various performance indicators and quality requirements that a product should meet as stipulated in the standard are called technical conditions, such as chemical composition, external dimensions, surface quality, physical properties, mechanical properties, process properties, internal structure, and delivery state, etc. 3. Assurance Conditions: According to the provisions of the technical conditions for metallic materials, the manufacturer should conduct inspections and ensure that the inspection results meet the specified requirements for performance, chemical composition, internal structure and other quality indicators, which are called assurance conditions. 4. Quality Certificate: The production of metallic materials, like the production of other industrial products, is carried out according to unified standard regulations, implementing a product factory inspection system; unqualified metallic materials are not allowed to be delivered. For delivered metallic materials, the manufacturer provides a quality certificate to guarantee its quality. The quality certificate for metallic materials not only specifies the name, specifications, number of delivered items, weight, etc. of the material, but also provides the complete inspection results of the specified guaranteed items. 5. Quality Certificate: The quality certificate is the confirmation and guarantee of the inspection results of this batch of products by the supplier, and it is also the basis for the purchaser to conduct re-inspection and use. 5. Quality Grades: According to different requirements for steel surface quality, shape, and dimensional tolerances, the quality of steel is divided into several grades. For example, first-grade products and second-grade products. Sometimes, different grades are set for a certain requirement. For example, for surface quality, it is divided into first-grade, second-grade, and third-grade; for surface decarburization depth, it is divided into group one, group two, etc., all indicating differences in quality. 6. Precision Grades: For some metallic materials, the standard specifies several dimensional tolerances, and according to the different sizes of dimensional tolerances, they are divided into several grades, called precision grades. Precision grades are divided into ordinary precision, higher precision, and high precision according to the allowed deviation. The higher the precision grade, the smaller the allowable dimensional deviation. When ordering, attention should be paid to including the precision grade requirements in the contract and other relevant documents. 7. Grade: The grade of metallic materials is the name given to each specific metallic material. The grade of steel is also called steel grade. The grades of metallic materials in China generally reflect the chemical composition. The grade not only indicates the specific variety of metallic materials, but also can be used to roughly judge its quality. In this way, the grade simply provides a common concept of the quality of specific metallic materials, bringing great convenience to production, use, and management. 8. Variety: The variety of metallic materials refers to products with different uses, shapes, production processes, heat treatment states, particle sizes, etc. 9. Model: The model of metallic materials refers to the code representing products of different shapes and categories, such as profiles and cemented carbides, using Chinese Pinyin (or Latin) letters and one or more numbers. The numbers indicate the nominal dimensions of the main parts. 10. Specifications: Specifications refer to different dimensions of metallic materials of the same variety or the same model. Generally, different dimensions have different tolerances. In product standards, the specifications of varieties are usually arranged in order from small to large. 11. Surface State: Mainly divided into bright and non-bright. Common in steel wire and steel strip standards, the main difference lies in whether bright annealing or general annealing is used. Polishing, grinding, pickling, and plating are also considered as surface states. 12. Edge State: The edge state refers to whether the strip steel is sheared or not. Sheared ones are sheared strip steel, and unsheared ones are unsheared strip steel. 13. Delivery State: The delivery state refers to the final plastic deformation processing or final heat treatment state of the product delivery. Those delivered without heat treatment include hot-rolled (forged) and cold-rolled states. Those treated with normalizing, annealing, high-temperature tempering, quenching and tempering, and solution treatment are collectively called heat-treated delivery states, or are called normalizing, annealing, high-temperature tempering, quenching and tempering states, etc. according to the heat treatment categories. 14. Material Hardness: This refers to the different hardness of steel obtained by using different heat treatments or degrees of work hardening. In some strip steel standards, it is divided into extra-soft strip steel, soft strip steel, semi-soft strip steel, low-hard strip steel, and hard strip steel. 15. Longitudinal and Transverse: The longitudinal and transverse directions mentioned in steel standards refer to the relative relationship with the rolling (forging) and drawing directions. Those parallel to the processing direction are called longitudinal; those perpendicular to the processing direction are called transverse. Samples taken along the processing direction are called longitudinal samples; samples taken perpendicular to the processing direction are called transverse samples. The fracture on the longitudinal sample is perpendicular to the rolling direction, so it is called a transverse fracture; the fracture on the transverse sample is parallel to the processing direction, so it is called a longitudinal fracture. 16. Theoretical Weight and Actual Weight: These are two different methods for calculating the delivery weight. Delivery by theoretical weight is the delivery weight calculated according to the nominal dimensions and density of the material. Delivery by actual weight is the delivery weight obtained by weighing (weighbridge) the material. 17. Nominal Dimensions and Actual Dimensions: Nominal dimensions refer to the nominal dimensions specified in the standard, which are the ideal dimensions hoped to be obtained during production. However, in actual production, the actual dimensions of steel are often larger or smaller than the nominal dimensions. The dimensions actually obtained are called actual dimensions. 18. Deviation and Tolerance: Because it is difficult to achieve the nominal dimensions in actual production, the standard stipulates an allowable difference between the actual dimensions and the nominal dimensions, which is called deviation. A negative difference is called a negative deviation, and a positive difference is called a positive deviation. The sum of the absolute values of the allowable positive and negative deviations specified in the standard is called the tolerance. Deviation has directionality, that is, it is represented by "positive" or "negative"; tolerance does not have directionality. 19. Delivery Length: There are four regulations for the delivery length of steel in current standards:

　　Fixed length, any steel whose length is within the range specified in the standard and has no fixed length is called the usual length. However, for the convenience of packaging, transportation, and measurement, when cutting steel, enterprises should cut it into several different lengths as appropriate, striving to avoid inconsistent lengths.

　　Those referred to as short-length, 20 in length. Refining method refers to the type of steelmaking furnace used, such as open-hearth furnace, electric arc furnace, electroslag furnace, vacuum induction furnace, and mixed steelmaking. The term "refining method" in the standard does not include deoxidation methods (such as fully deoxidized killed steel, semi-deoxidized semi-killed steel, and rimmed steel) and casting methods (such as top pouring, bottom pouring, and continuous casting). 2l Chemical composition (product composition) refers to the chemical composition of steel products, including the main components and impurity elements, with the content expressed as a percentage by weight. 22 Smelting composition The smelting composition of steel refers to the chemical composition of steel at the end of smelting (such as in-furnace deoxidation) and during the middle of casting. 23 Finished product composition The finished product composition of steel, also called the verification analysis composition, refers to the chemical composition obtained by drilling or planing samples from finished steel products according to the specified method (see GB/T222 for details) and analyzing them according to the specified standard method. The finished product composition of steel is mainly used for acceptance of steel by users or inspection departments. The manufacturer generally does not perform a complete finished product analysis, but should ensure that the finished product composition meets the standard requirements. For some major products, or sometimes due to certain reasons (such as process changes, unstable quality, smelting composition approaching the upper and lower limits, failure to obtain smelting analysis, etc.), the manufacturer also performs finished product composition analysis. 24 High-quality steel and high-grade high-quality steel (with the letter A) Also called quality steel and high-grade quality steel, the difference lies in that high-grade high-quality steel is superior to high-quality steel in some or all of the following aspects. ① Narrower carbon content range; ② Reduced harmful impurity content (mainly sulfur and phosphorus); ③ Guaranteed higher purity (referring to low inclusion content); ④ Guaranteed higher mechanical properties and processability. The steel market shows diverging views from domestic large steel companies on the market outlook. Ansteel cut its April plate prices on March 18. Last week, Baosteel raised the futures prices of its major products for April. However, Wuhan Iron and Steel and Shougang did not follow Baosteel's lead in their main products, and even Shagang introduced a price reduction policy with subsidies.