1.2311

Plastic Injection Moulds – Widely used for manufacturing medium to large plastic injection molds. Compression Moulds – Suitable for molds used in compression molding processes. Mould Bases and Inserts – Ideal for mold bases, supports, and cavity inserts. Die Casting Dies – Used for zinc and aluminum die casting applications. Prototype Moulds – Perfect for short-run or prototype molds due to ease of machining. Blow Moulds – Applied in the production of plastic bottles and containers. Tooling Components – Used in jigs, fixtures, and tooling supports for molding processes. Automotive Parts Moulds – Molds for plastic automotive interior parts and trim. Consumer Electronics Housings – Molds for casings and components in electronics. Medical Device Moulds – Precision molds used in medical and packaging industries.

We are a trusted supplier, stockist, and dealer of 1.2311 Plastic Mould Steel (P20 grade), serving mold makers, tool manufacturers, and engineering industries across India and international markets. Our 1.2311 steel is available in various forms such as round bars, flat bars, plates, and blocks, cut to customer specifications. Each batch is supplied with mill test certificates (MTC) to ensure quality, consistency, and traceability.

Pre-Hardened Condition: Typically supplied with a hardness of 28 to 32 HRC (Rockwell Hardness C). This pre-hardened state allows for easy machining without the need for additional heat treatment. After Heat Treatment: If further hardened, 1.2311 steel can achieve hardness values up to 50 HRC, but this is not common for most mold applications as it may cause distortion. Surface Hardening: Surface treatments like nitriding can increase surface hardness up to 60–65 HRC, enhancing wear resistance while keeping a tough core.

Pre-Hardened Supply: 1.2311 is usually supplied in a pre-hardened condition with hardness around 28–32 HRC, ready for machining. Annealing: To soften the steel for easier machining, anneal by heating to 680–720°C, hold until uniform temperature is reached, then cool slowly in the furnace. This reduces hardness to about 180–220 HB. Hardening : Heat to 830–870°C for austenitizing, soak depending on section size (typically 30–60 minutes). Quench in oil or polymer to form martensite. Achieves hardness up to 50 HRC but risks distortion. Tempering: Temper at 500–650°C after quenching to relieve stresses and improve toughness. Tempering temperature controls the final hardness and toughness balance. Nitriding: Heat in a nitrogen-rich atmosphere at 500–530°C to harden the surface. Surface hardness can reach 60–65 HRC without affecting the core toughness.

Preheating: Heat the steel gradually to prevent thermal shock. Preheat in stages: first to around 300–400°C, then to 600–650°C. Austenitizing (Hardening Temperature): Heat uniformly to 830–870°C. Hold for sufficient time based on thickness (usually 30–60 minutes per 25 mm of thickness). Quenching: Quench in oil or polymer medium to cool rapidly and form martensitic structure. Small sections may be air cooled carefully to reduce distortion. Tempering: Temper immediately after quenching at 500–650°C to reduce brittleness and improve toughness. Tempering time depends on the section size. Resulting Hardness: Core hardness can reach up to 50 HRC after hardening and tempering. However, most plastic mould applications use the steel in the pre-hardened state (28–32 HRC) to avoid distortion.

Preheating: Preheat the steel to 250–350°C before welding to reduce thermal stress. Welding Methods: Use TIG (GTAW) or MIG (GMAW) welding processes. Select matching or compatible filler materials designed for low-alloy steels. Interpass Temperature: Maintain an interpass temperature of around 300–350°C to avoid hard zones and cracking. Post-Weld Heat Treatment (PWHT): Stress relief annealing is recommended after welding by heating to 600–630°C for 2–4 hours, followed by slow cooling. This helps to relieve residual stresses and improve toughness. Machining After Welding: Welded areas may become harder or more brittle, requiring additional machining or grinding.

Pre-Hardened Supply: Typically supplied with a hardness of 28–32 HRC, allowing for easy machining without the need for heat treatment after machining. Tool Compatibility: Machines well with high-speed steel (HSS) and carbide tools, supporting a variety of machining operations such as milling, turning, drilling, and grinding. Surface Finish: Capable of producing fine surface finishes and maintaining tight dimensional tolerances, essential for mold cavities. Tool Wear: The moderate hardness ensures lower tool wear compared to fully hardened steels, which reduces machining costs. Polishing: Can be polished to a mirror-like finish, a critical requirement for many plastic molding applications.