20CrMnTi square steel is a versatile low-alloy carburizing steel widely utilized in mechanical engineering and automotive manufacturing. As a member of the chromium-manganese-titanium alloy series, it strikes a balance between high surface hardness, core toughness, and excellent processability, making it a preferred material for components subjected to both wear and impact loads. Its chemical composition is carefully formulated: 0.17–0.23% carbon (C) provides the base for carburizing, 1.00–1.30% chromium (Cr) enhances hardenability and wear resistance, 0.80–1.10% manganese (Mn) boosts tensile strength and toughness, and 0.04–0.10% titanium (Ti) refines the grain structure—preventing over-coarsening during high-temperature heat treatment, which preserves fatigue resistance. Trace elements like silicon and sulfur are present in minimal amounts to optimize machinability. The core advantage of 20CrMnTi square steel lies in its dual-property profile after heat treatment. Carburizing infuses carbon into the surface, followed by quenching and tempering, resulting in a hard surface (HRC 58–62) that resists abrasive wear, paired with a ductile core (HRC 30–45) that absorbs shock without fracturing. This makes it ideal for parts that endure dynamic loads and repeated contact. The square cross-section of this material offers unique practical benefits. It is commonly processed into automotive transmission gears, drive shafts, pinions, and differential components—where a square blank simplifies machining into precise, load-bearing shapes. In industrial machinery, it is used for sprockets, bushings, and load-bearing brackets, as its uniform cross-section ensures consistent mechanical performance across the part. The square form also facilitates efficient forging and cutting, reducing material waste and production time. 20CrMnTi square steel exhibits excellent processing characteristics. It has high forgeability, allowing hot forging into complex shapes without cracking. After annealing, its machinability improves significantly, making it easy to turn, mill, or drill. The titanium content is particularly critical during carburizing: it forms stable carbides that inhibit grain growth, ensuring the surface remains fine-grained and durable. Post-heat treatment, the material maintains dimensional stability—essential for high-precision components. In summary, 20CrMnTi square steel is a reliable, cost-effective material that combines mechanical strength, wear resistance, and processability. Its widespread use in automotive and machinery industries underscores its value in producing components that demand both durability and performance. Whether in transmission systems or industrial equipment, this alloy steel remains a go-to choice for engineers seeking a balance of functionality and efficiency.