The material is WCB; should it be classified as carbon steel or low-alloy steel?

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The material is WCB; should it be classified as carbon steel or low-alloy steel? It is equivalent to 25#/35# steel, as it has good fluidity and is commonly used in casting applications. Its properties are similar to those of ZG230-450, which belongs to carbon cast steel. According to ASTM standards, the main chemical components are: C (less than or equal to 0.25), Si (less than or equal to 0.60), Mn (less than or equal to 0.70), P (less than or equal to 0.04), S (less than or equal to 0.045); residual elements include Cr (less than or equal to 0.50), Ni (less than or equal to 0.50), Mo (less than or equal to 0.20), Cu (less than or equal to 0.30), V (less than or equal to 0.03). What is the material of ST 37-2? What is the material of RST 37-2? Simply put, RST 37-2 is a German-standard material, equivalent to China’s Q235 material. As defined by EN10027-2, this standard provides a numerical identifier for the steel’s composition, but it is not a production specification sheet. They are based on Germany’s “Werkstoff” coding system: 1. The digits XXYY – the first digit represents steel, while the subsequent digits (XX) indicate the characteristics of that steel. Examples are as follows: 00 Base Steel; 01 Ordinary structural steel with a yield strength of less than 500 N/mm²; 03 Steel with a carbon content of less than 0.12% or a yield strength of less than 400 N/mm²; 04 Steel with a carbon content between 0.12% and 0.25%, or a yield strength between 400 and 500 N/mm²; 05 Steel with a carbon content between 0.25% and 0.55%, or a yield strength between 500 and 700 N/mm²; 43 Stainless steel with Ni > 2.5%; 44 Stainless steel with Ni > 2.5% + Mo; 48 Heat-resistant steel with Ni > 2.5%. YY represents the serial number assigned by the Standards Committee. For example: Both 1.4401 and 1.4404 are 316-type stainless steel, as indicated by the number 44. The last two digits indicate that although the two steels are similar, their alloy contents differ; however, they do not show by how much. 1.4401 corresponds to 316, while 1.4404 corresponds to 316L. What does material 20G mean? What are sheets made of this material commonly used for? Ms. Wang from the procurement department of a machinery factory in Nanjing called to ask: When purchasing steel recently, she found plates labeled as 20G; she is wondering what their composition and mechanical properties are What is the difference from the common Q235 material? Online answer: Steel of 20G grade is high-quality carbon structural steel, intended for use in boilers. Its carbon content ranges from 0.16% to 0.24%, with a tensile strength of 410 Mpa and a yield strength of 230–250 Mpa. There is also a 20-grade grade in high-quality carbon structural steel; its carbon and silicon contents are slightly higher than those of 20G, while its tensile strength and yield strength remain roughly the same. Steel of Q235 grade is a common carbon structural steel; its carbon and silicon contents are lower than those of 20G, and its tensile strength and yield strength are also relatively lower. Obviously, although steel plates made of Q235 and 20G can often be used interchangeably in many applications, the mechanical properties of 20G steel are superior. Consequently, its market price is relatively higher. In situations where high tensile strength and impact resistance are required, steel plates made of 20G should be chosen; examples include the manufacture of boilers. For general applications, considering the purchase cost, it is more appropriate to choose steel plates made of Q235 material. 316L and 316Ti: 316Ti stainless steel is obtained by adding Ti to 316 stainless steel in order to improve its resistance to intergranular corrosion. It is also a variant of 316 stainless steel, used in equipment that must resist sulfuric acid, phosphoric acid, acetic acid, and vinegar. Physical properties: Chemical composition of 316 stainless steel – C: ≤0.08, Si ≤1.00, Mn ≤2.00, P ≤0.035, S ≤0.030; Ni: 11.00–14.00, Cr: 16.00–19.00, Mo: 1.80–2.50; Ti: ≥5%C% + 0.70. It is also commonly referred to as Mo2Ti or 316Ti. 316L stainless steel (00Cr17Ni14Mo2) is a ultra-low carbon version of 0Cr17Ni12Mo2, and it exhibits better resistance to intergranular corrosion compared to 0Cr17Ni12Mo2 (SUS316). Chemical composition of 316L stainless steel: C≤0.03, Si≤1.00, P≤0.035, S≤0.03; Ni: 12.0–15.0, Cr: 16.0–18.0, Mo: 2.0–3.0. Tensile strength: 620 MPa minimum; Yield strength: 310 MPa minimum; Elongation: 30% minimum; Area reduction: 40% minimum. Characteristics: Due to the addition of Mo, it exhibits excellent corrosion resistance, resistance to atmospheric corrosion, and high-temperature strength, allowing it to be used in harsh conditions ； Excellent work hardening property (non-magnetic) ； Excellent high-temperature strength ； Non-magnetic in the solution-treated state ； Cold carbon steel: 20#, Q235A, Q235B, 20G, ASTM A234 WPB, etc ； Stainless steel: 1Cr18Ni9Ti, 0Cr18Ni10Ti, 0Cr18Ni9, 00Cr19Ni10, 0Cr17Ni12Mo2Ti, 00Cr17Ni14Mo2, 00Cr17Ni12Mo2, WP/TP/F 304, WP/TP/F 304L, WP/TP/F 316, WP/TP/F 316L, WP/TP/F 321, WP/TP/F 310, etc ； Alloy steels include 16Mn, 16MnR, Cr5Mo, Cr9Mo, 12Cr1MoV, 10CrMo910, 15CrMo, A335 WP22/WP11/WP12/WP5/P91, A234 WP5/WP9/WP11/WP22/WP91, A420 WPL6, A860 WHPY 45/52/60/65/70/70, etc. A860 WHPY52 belongs to the X-grade low-temperature carbon steel and is also considered an alloy steel. A694 F65 is a low-temperature carbon steel, while WP9 is an imported alloy steel that corresponds to Cr9Mo in China; it is often used in the manufacture of certain special types of pipe fittings. FOR H-71401 is equivalent to alloy steel P9. A420 WPL6 refers to low-temperature seamless or welded pipe fittings according to American standards; the corresponding pipe material is A333 Gr.6, which is generally used in environments with temperatures as low as -45 degrees Celsius. In China, 16Mn pipes are usually used as a substitute, as 16Mn can be used in working environments with temperatures down to -40 degrees Celsius