Tool Steel Selection Guidelines for High Volume Injection Moulding Tooling Baseline Fabrication
High-volume injection moulding baseline tooling demands martensitic stainless or pre-hardened steels matched to polymer abrasiveness and cycle volume.
Bohler M333
Meaning
Corrosion-resistant plastic mould steel provides high-performance tooling material for processing chemically aggressive polymers like polyvinyl chloride. Developed specifically for injection moulding, bohler m333 offers exceptional polishability to achieve high-gloss surfaces on finished parts. This grade maintains stable dimensions during heat treatment, reducing the need for post-mould corrective machining.
Alloy Design
Chromium alloying is critical to prevent corrosive attacks from acid byproducts released during the moulding of chlorinated resins. To enhance this protective effect, bohler m333 utilizes a balanced matrix that minimizes carbide precipitation along the grain boundaries. This design preserves the chromium content in solid solution, ensuring uniform corrosion resistance across the entire cavity.
Highly refined steel prevents localized pitting and micro-cracking, which are common issues in standard grades of tool steel that are exposed to aggressive gasses during long production runs.
Processing Benefit
Optical clarity in transparent polymer products relies on a flawless mirror finish within the mould cavity. Using bohler m333 enables manufacturers to achieve a superb polish that prevents surface cosmetic defects on plastic lenses. The reduction in rejection rates lowers the overall cost per part in high-volume production.
Tooling Wear
High mechanical stress during high-speed moulding runs can accelerate mold degradation if the steel lacks tough structures. Utilizing bohler m333 helps mitigate heat cracking and erosive wear from glass-filled resins. The resulting thermal conductivity helps maintain short cycle times and prevents premature tooling failure.