Die Steel Review: D2 vs S7 vs Carbide Inserts
压印模具钢评测：D2、S7 与硬质合金镶块
标签：模具钢, D2, 硬质合金, 工具评测
压印模钢直接决定批量成本：D2 淬硬到 HRC 58–62，耐磨性好、韧性中等，适合 10 万次以内的铜与黄铜章模；S7 淬硬到 HRC 54–58，抗冲击强，适合深浮雕与高吨位反复冲击但磨损稍快；硬质合金镶块硬度 HRA 88 以上，寿命可达 D2 的 5–8 倍，但脆性高、须数控磨削加工，模价约 3 倍。经验法则：2 万枚以内选 S7，2–10 万选 D2，10 万以上或压含镍硬坯料用镶块。每次翻修磨削量 0.05–0.1 mm，三次翻修后需重新评估棱口。
Die steel decides batch economics: D2 at HRC 58–62 wears well with medium toughness and suits copper/brass medal dies up to about 100 k strikes; S7 at HRC 54–58 takes impact better—good for deep relief and high-tonnage repetition, though it wears faster. Carbide inserts (HRA 88+) last 5–8× longer than D2 but are brittle, need CNC grinding and cost about 3×. Rule of thumb: S7 under 20 k strikes, D2 for 20–100 k, carbide above 100 k or on hard nickel-bearing blanks. Allow 0.05–0.1 mm per regrind and reassess the edge after three refurbishments.