Chemical Composition of C45 Steel Plate, JIS S45C, 1045 Steel, EN8 Steel, EN8D Steel, and DIN 1.1191 

The materials C45 Plastic Mould Steel Plate, C45 Carbon Steel, JIS S45C, 1045 Steel, EN8 Steel, EN8D Steel, and DIN 1.1191 are all medium-carbon steels widely recognized for their versatility across numerous manufacturing sectors. These grades share a similar fundamental chemical composition—usually characterized by a carbon content of 0.40% to 0.50%, which ensures a strong balance among hardness, tensile strength, and ductility.

C45 Plastic Mould Steel Plate is engineered explicitly for plastic mould manufacturing, offering enhanced machinability and uniform hardness for precision tooling that endures repetitive forming cycles. Its superior polishability helps achieve smooth surface finishes demanded in plastic molding applications. C45 Carbon Steel, along with its equivalents such as JIS S45C (Japanese standard) and AISI 1045 Steel (American standard), provides excellent mechanical strength and resilience, making these steels ideal for components such as shafts, gears, axles, and connecting rods in the automotive and machinery industries.

EN8 Steel and its variant EN8D Steel are British Standard medium carbon engineering steels, appreciated for their adaptability to heat treatment, which optimizes mechanical properties like hardness and toughness. EN8D has a slightly higher carbon content, giving it slightly higher strength and improved resistance to wear and fatigue than EN8. DIN 1.1191, the German equivalent, is produced to strict international standards, offering harmonized chemistry and physical attributes to match the needs of global engineering firms.

All these steels can be delivered as rolled plates, bars, or custom-cut pieces, and are suitable for both surface and core hardening by flame or induction processes. Industries rely on these materials for tool and mold bases, heavy-duty machine components, crankshafts, spindles, bolts, and general engineering, where robust mechanical properties and dimensional stability are crucial.

When choosing between these grades, engineers consider factors such as required hardness, toughness, machinability, and the intended heat treatment. Understanding the precise chemical composition helps select the right steel for plastic molding, forging, heavy engineering, or precision mechanical applications, ensuring optimal performance, longevity, and reliability in service. Refer to the detailed chemical composition table below for a direct comparison and informed decision-making.