24 common metal materials and their properties

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1, 45 – High-quality carbon structural steel; it is the most commonly used medium-carbon quenched and tempered steel. Key features: It is the most widely used medium-carbon quenched and tempered steel, offers good overall mechanical properties, has low hardenability, and is prone to cracking when quenched in water. Small parts are suitable for quenching and tempering treatment, while large parts are suitable for normalizing treatment. Application examples: It is mainly used to manufacture high-strength moving parts, such as turbine blades and compressor pistons. Shafts, gears, racks, worms, etc. For welded parts, pay attention to preheating before welding and stress-relief annealing after welding. 2. Q235A (A3 steel) – the most commonly used carbon structural steel. Key features: high plasticity, toughness, and weldability; good cold stamping properties; as well as a certain level of strength and excellent cold bending performance. Application examples: Widely used in parts and welded structures with general requirements. Such as tie rods, connecting rods, pins, shafts, screws, nuts, rings, brackets, frames, building structures, bridges, etc., which are not subject to high stresses. 3. 40Cr – One of the most widely used steel grades; it belongs to the category of alloy structural steels. Its main characteristics are: after quenching and tempering, it exhibits good overall mechanical properties, low-temperature impact toughness, and low sensitivity to notches. It has good hardenability; oil cooling allows for high fatigue strength, while water cooling can cause cracks in parts with complex shapes. Its cold-forming capacity is moderate. After tempering or quenching and tempering, it has good machinability, but its weldability is poor, and cracks tend to occur. Preheating to 100–150°C before welding is necessary. It is generally used in its quenched and tempered state; it can also be subjected to carburitriding and high-frequency surface hardening treatments. Application examples: After quenching and tempering, it is used to manufacture parts that operate at medium speeds and under moderate loads, such as machine tool gears, shafts, worms, spline shafts, and ejector pin sleeves. After quenching and high-frequency surface hardening, it is used to produce parts with high surface hardness and wear resistance, such as gears, shafts, spindles, crankshafts, mandrels, sleeves, pins, connecting rods, screws, nuts, and intake valves. After quenching and medium-temperature tempering, it is used to create parts that are subject to heavy loads and medium-speed impacts, such as oil pump rotors, sliders, gears, and spindles. After quenching and low-temperature tempering, it is used to manufacture parts that can handle heavy loads, low impacts, and have high wear resistance, such as worms, spindles, shafts, and rings. Carbonitriding is employed to produce transmission parts of larger size with higher low-temperature impact toughness, such as shafts and gears. 4. HT150 – Gray cast iron. Examples of applications: gearboxes, machine tool beds, housings, hydraulic cylinders, pump bodies, valve bodies, flywheels, cylinder heads, pulleys, bearing covers, etc. 5, 35 – Common materials for various standard parts and fasteners. Main characteristics: appropriate strength, good plasticity, high cold formability, and decent weldability. Local upsetting and drawing are possible at low temperatures. It has low hardenability; examples of its use after normalizing or quenching and tempering: it is suitable for manufacturing parts with small cross-sections that can withstand large loads, such as crankshafts, levers, connecting rods, hooks, etc., as well as various standard parts and fasteners. 6. 65Mn – a commonly used spring steel. Examples of its applications include various small-sized flat and circular springs, seat cushion springs, and spring coils; it can also be used to manufacture spring rings, valve springs, clutch components, brake springs, cold-rolled helical springs, and snap rings. 7. 0Cr18Ni9 – the most commonly used stainless steel (American grade 304, Japanese grade SUS304). Properties and applications: It is the most widely used as a stainless heat-resistant steel, in applications such as food processing equipment, general chemical processing equipment, and equipment used in the nuclear industry. 8. Cr12 – A commonly used cold-working die steel (U.S. steel grade D3, Japanese steel grade SKD1). Properties and applications: Cr12 steel is a widely used cold-working die steel that belongs to the high-carbon, high-chromium type of ledeburite steel. This steel possesses good hardenability and excellent wear resistance ； Due to the high carbon content of 2.3% in Cr12 steel, it has poor impact toughness, is prone to brittle fracture, and tends to form uneven eutectic carbides ； Due to its excellent wear resistance, Cr12 steel is widely used in the manufacture of cold stamping dies, punches, blanking dies, cold heading dies, punch and die sets for cold extrusion, drill bushings, gauges, wire drawing dies, imprinting dies, thread rolling dies, drawing dies, as well as cold pressing dies for powder metallurgy, where low impact loads and high wear resistance are required. 9. DC53 – A commonly used Japanese-imported cold-work die steel. Properties and applications: A high-strength and high-toughness cold-work die steel; it is a steel grade produced by Nippon Steel & Sumitomo Metal Corporation in Japan. After high-temperature tempering, it possesses high hardness and high toughness, as well as good wire cutting properties. Used for precision cold stamping dies, drawing dies, thread rolling dies, cold cutting dies, punches, etc. 10, SM45 – ordinary carbon plastic mold steel (Japanese grade S45C). 10, DCCr12MoV – wear-resistant chromium steel of domestic production; it has a lower carbon content than Cr12 steel, and the addition of Mo and V improves the uniformity of carbides. Mo helps to reduce carbide segregation and enhances hardenability, while V refines the grain structure and increases toughness. This steel possesses high hardenability; sections up to 400 mm in diameter can be fully hardened. It maintains good hardness and wear resistance at temperatures between 300–400°C. It offers higher toughness compared to Cr12, experiences minimal volume change during quenching, and boasts high wear resistance along with excellent overall mechanical properties. Therefore, it can be used to manufacture various molds with large cross-sections, complex shapes, and those subject to significant stress, such as ordinary drawing dies, punching dies, blanking dies, trimming dies, bending dies, thread rolling dies, cold extrusion dies, cold cutting scissors, circular saws, standard tools, and measuring instruments. 11. SKD11 – A tough chromium steel produced by Hitachi, Japan. It features improved casting structure in the steel, with finer grains; it offers better toughness and wear resistance compared to Cr12MOV, thereby extending the service life of molds. 12. D2 – A high-carbon, high-chromium cold work steel manufactured in the United States. It possesses high hardenability and wear resistance, as well as good oxidation resistance at high temperatures. It also has good rust resistance after quenching and polishing, with minimal deformation during heat treatment. It is suitable for manufacturing various cold work molds, cutting tools, and measuring instruments that require high precision and long service life, such as drawing dies, cold extrusion dies, and cold shearing tools. 13. SKD11(SLD) – a high-chromium steel with high toughness and no deformation; produced by Hitachi, Japan. Due to the increased contents of Mo and V in this steel, its casting structure is improved, the grain size is reduced, and the morphology of the carbides is enhanced. As a result, this steel exhibits higher strength and toughness (such as bending strength, deflection, impact toughness, etc.) compared to SKD1 and D2; its wear resistance is also increased, and it has greater resistance to tempering. Practice has shown that the service life of molds made from this steel is longer than that of those made from Cr12MoV. It is commonly used to manufacture molds that require high performance, such as drawing dies and molds for impact grinding wheels. 14. DC53 – A high-toughness, high-chromium steel produced by Nippon Datong Corporation. Its hardness after heat treatment is higher than that of SKD11; after tempering at high temperatures (520–530°C), it can reach a hardness of 62–63 HRC. In terms of strength and wear resistance, DC53 exceeds SKD11, and its toughness is twice that of SKD11. This high toughness reduces the occurrence of cracks and fissures in cold-work die manufacturing, thereby extending their service life. It also has low residual stress, and high-temperature tempering further reduces this stress. Cracks and deformation resulting from wire cutting are minimized, and its machinability and grindability are superior to those of SKD11. It is used in precision stamping dies, cold forging, deep drawing dies, etc. 15. SKH-9 – A general-purpose high-speed steel with excellent wear resistance and toughness, produced by Hitachi, Ltd. in Japan. It is used in cold forging dies, slitting machines, drills, reamers, punches, etc. 16. ASP-23 – Powder metallurgy high-speed steel of Swedish origin. It features an extremely uniform distribution of carbides, good wear resistance, high toughness, ease of machining, and dimensional stability after heat treatment. It is used for various cutting tools that require long service life, such as punches, deep drawing dies, drilling dies, milling cutters, and shear blades. 17. P20 – Plastic molds of standard size; manufactured in the United States. Suitable for electrochemical machining. Pre-hardened to HB270-300 upon leaving the factory; hardness after quenching is HRC52. 18. 718 – Plastic molds of high standards, both large and small; manufactured in Sweden. Particularly suitable for electrochemical machining processes. Pre-hardened at HB290-330 upon leaving the factory; hardness after quenching is HRC52.
19. Nak80 – Plastic molds with a high degree of surface finish and precision; manufactured by Nippon Daiyo Kogyo in Japan. Pre-hardened at HB370-400 upon leaving the factory; hardness after quenching is HRC52.
20. S136 – Plastic molds that require corrosion resistance as well as a high-quality surface finish; manufactured in Sweden. Pre-hardened at HB<215 upon leaving the factory; hardness after quenching is HRC52. 21. H13 – A commonly used die material for die-casting aluminum, zinc, magnesium, and their alloys. It is also used in hot stamping dies and aluminum extrusion dies. 22. SKD61 – A high-quality die material produced by Hitachi in Japan; thanks to the electroslag remelting process, its service life is significantly longer than that of H13. It is used in hot stamping dies and aluminum extrusion dies. 23. 8407 – A high-quality die material from Sweden. It is used in hot stamping dies and aluminum extrusion dies. 24. FDAC – Sulfur is added to enhance its machinability. The pre-hardened hardness upon delivery is 38–42 HRC; it can be directly subjected to engraving and machining without the need for quenching or tempering treatments. It is used for small-batch molds, simple molds, various resin products, sliding components, and mold parts requiring short lead times. It’s also suitable for zipper molds and eyeglass frame molds.