1.What are the material requirements for pen molds (pen tip molds)?
High hardness and high wear resistance: to withstand the wear of stainless steel strip during high-speed stamping.
High toughness: to prevent brittle cracking, especially at the cutting edges of precision, thin-walled dies.
Excellent dimensional stability: minimal heat treatment deformation to ensure die precision.
Good polishability: the die cavity requires mirror polishing to ensure a smooth pen tip surface.
Uniform microstructure: any segregation or banding will lead to premature die failure.
2.What is the complete production chain for cold-rolled coils?
Steelmaking → Casting into ingots or continuously cast billets → Hot rolling into slabs/bars → (Forging into modules) → Softening annealing → Cold rolling/cold drawing
For manufacturing mold flat steel and modules: After hot rolling and forging, special steel undergoes "cold rolling" (actually "cold-rolled sheet" or "cold-rolled flat steel") or "cold drawing" (for round bars) to obtain more precise dimensions, a finer surface, and improved microstructure. The product at this stage is "cold-rolled mold steel coil" or "cold-rolled mold steel strip."
Subsequent processing: After purchasing this cold-rolled refined material, mold manufacturers will perform the following:
Cutting: Cutting the coil or sheet into mold blanks.
Rough machining.
Heat treatment: Performing precision quenching and tempering to achieve the final hardness.
Fine machining and polishing: Fabricating the mold.
3.Is it okay to use ordinary cold-rolled coils (such as SPCC) directly?
Ordinary cold-rolled coils (such as common low-carbon steels SPCC and SPCD) are fundamentally different from die steels:
**Composite Composition:** Ordinary cold-rolled coils have a low carbon content (<0.1%) and few alloying elements. Die steels have a high carbon content (>0.8%) and contain large amounts of alloying elements such as chromium, molybdenum, and vanadium, which are the basis for their high hardness and high wear resistance.
**Performance Requirements:** Even with heat treatment, ordinary cold-rolled coils cannot achieve the hardness and wear resistance of die steel and will wear out quickly and become unusable.
**Different Manufacturing Processes:** Die steel cold-rolled coils undergo complex softening processes such as spheroidizing annealing before and after rolling to facilitate subsequent processing and final heat treatment.
4.What is the relationship between cold rolling and pen-making molds?
Cold rolling is a processing method that improves the dimensional accuracy and surface quality of materials, not a type of material. Pen molds use special alloy mold steel that has undergone cold rolling.
5.If you are involved in pen mold manufacturing or procurement, what should you pay attention to?
Suppliers: Professional mold steel suppliers (such as Longji, Uddeholm, Tatung, Hitachi, etc., or their agents).
Purchase Form: Not the broad concept of "cold-rolled coils," but specific high-quality mold steel raw materials, which may be in the form of "pre-hardened flat steel," "mirror-polished sheets," or "annealed modules" requiring in-house heat treatment.
Key Indicators: Focus on the steel grade, hardness, purity, microstructure uniformity, and polishing grade.