{ "slug": "heat-treatment-conditions", "title": "CNC 合金的热处理与状态代号", "description": "CNC 合金的状态代号：钢的淬火+回火硬度随温度变化，6061-O 至 T651、7075-T73 与 17-4PH H900 至 H1150，并给出 NACE 限制。", "lang": "zh", "tables": [ { "caption": "碳钢与合金钢——热处理工艺及典型硬度", "columns": [ "工艺", "作用", "典型硬度", "典型应用", "适用标准" ], "rows": [ { "工艺": "Annealing", "作用": "加热到临界温度以上或附近，然后在炉内极慢冷却，以软化并消除应力", "典型硬度": "160–217 HB (grade-dependent)", "典型应用": "机加工毛坯、冷成形、重新淬火前的去应力", "适用标准": "GB/T 16923; ASTM A29; SAE J412" }, { "工艺": "Normalizing", "作用": "加热到 Ac3/Acm 以上 30–50 °C，然后在静止空气中冷却，以细化晶粒并均匀组织", "典型硬度": "187–300 HB (grade-dependent)", "典型应用": "大型锻件、淬火易变形的重要结构件", "适用标准": "GB/T 16923; ASTM A29" }, { "工艺": "Quenching + tempering", "作用": "奥氏体化后在水或油中淬成马氏体，再加热到 Ac1 以下回火，以消除应力并调整硬度", "典型硬度": "24–57 HRC (depends on tempering temperature)", "典型应用": "成品工程零件：轴、齿轮、紧固件", "适用标准": "GB/T 16924; ASTM A29" }, { "工艺": "Quench and high temper (Q&T)", "作用": "淬火后在 500–650 °C 高温回火，得到回火索氏体，强度与韧性配合最佳", "典型硬度": "28–34 HRC (common supply band)", "典型应用": "连杆、螺栓、齿轮、承受交变载荷的轴", "适用标准": "GB/T 16924; GB/T 7232" } ] }, { "caption": "退火态与正火态 1045 钢的硬度分别是多少？", "columns": [ "状态", "抗拉强度（MPa）", "屈服强度（MPa）", "伸长率（%）", "硬度", "来源" ], "rows": [ { "状态": "Hot-rolled / annealed", "抗拉强度（MPa）": "565 (typical hot-rolled)", "屈服强度（MPa）": "310", "伸长率（%）": "16", "硬度": "163 HB; annealed band 160–200 HB", "来源": "S21 / S22 / S5" }, { "状态": "Normalized", "抗拉强度（MPa）": "640", "屈服强度（MPa）": "410", "伸长率（%）": "22", "硬度": "187 HB", "来源": "S6 / S5" }, { "状态": "Quenched and tempered", "抗拉强度（MPa）": "—", "屈服强度（MPa）": "—", "伸长率（%）": "—", "硬度": "220–290 HB", "来源": "S5" }, { "状态": "As-quenched (water, surface)", "抗拉强度（MPa）": "—", "屈服强度（MPa）": "—", "伸长率（%）": "—", "硬度": "55–60 HRC", "来源": "S5" }, { "状态": "Flame / induction hardened (surface)", "抗拉强度（MPa）": "—", "屈服强度（MPa）": "—", "伸长率（%）": "—", "硬度": "55–58 HRC, case depth 1.5–5 mm", "来源": "S5" } ] }, { "caption": "4140 钢预硬态供货硬度是多少？", "columns": [ "状态 / 回火温度", "抗拉强度（MPa）", "屈服强度（MPa）", "伸长率（%）", "硬度", "来源" ], "rows": [ { "状态 / 回火温度": "Annealed", "抗拉强度（MPa）": "~655", "屈服强度（MPa）": "~415", "伸长率（%）": "25", "硬度": "197–217 HB", "来源": "S4" }, { "状态 / 回火温度": "Normalized", "抗拉强度（MPa）": "~1,020", "屈服强度（MPa）": "~650", "伸长率（%）": "17", "硬度": "250–300 HB", "来源": "S4" }, { "状态 / 回火温度": "As-quenched (oil)", "抗拉强度（MPa）": "—", "屈服强度（MPa）": "—", "伸长率（%）": "—", "硬度": "55–60 HRC", "来源": "S4" }, { "状态 / 回火温度": "Q&T at 205 °C", "抗拉强度（MPa）": "~2,000", "屈服强度（MPa）": "~1,600", "伸长率（%）": "8", "硬度": "52–57 HRC", "来源": "S4" }, { "状态 / 回火温度": "Q&T at 315 °C", "抗拉强度（MPa）": "~1,700", "屈服强度（MPa）": "~1,450", "伸长率（%）": "10", "硬度": "45–50 HRC", "来源": "S4" }, { "状态 / 回火温度": "Q&T at 425 °C", "抗拉强度（MPa）": "~1,400", "屈服强度（MPa）": "~1,250", "伸长率（%）": "12", "硬度": "38–42 HRC", "来源": "S4" }, { "状态 / 回火温度": "Q&T at 540 °C (standard HT)", "抗拉强度（MPa）": "1,000–1,100", "屈服强度（MPa）": "850–950", "伸长率（%）": "18", "硬度": "28–32 HRC", "来源": "S4" }, { "状态 / 回火温度": "Q&T at 650 °C (high ductility)", "抗拉强度（MPa）": "~850", "屈服强度（MPa）": "~700", "伸长率（%）": "22", "硬度": "24–28 HRC", "来源": "S4" }, { "状态 / 回火温度": "Pre-hardened as-supplied", "抗拉强度（MPa）": "—", "屈服强度（MPa）": "—", "伸长率（%）": "—", "硬度": "28–34 HRC", "来源": "S4" } ] }, { "caption": "钢在淬火后、回火前有多硬？", "columns": [ "钢种", "淬火介质", "淬火态（HRC）", "回火后使用硬度", "备注" ], "rows": [ { "钢种": "1045", "淬火介质": "Water", "淬火态（HRC）": "55–60", "回火后使用硬度": "220–290 HB (Q&T)", "备注": "淬透性低的碳钢；大截面心部会软化" }, { "钢种": "4140", "淬火介质": "Oil", "淬火态（HRC）": "55–60", "回火后使用硬度": "28–32 HRC (tempered at 540 °C)", "备注": "Cr-Mo 合金钢，淬透性深；大截面优先选它" } ] }, { "caption": "淬火+回火是什么意思，为什么要规定？", "columns": [ "钢种", "Q&T 供货区间", "仅淬火后", "为什么要回火" ], "rows": [ { "钢种": "1045", "Q&T 供货区间": "220–290 HB", "仅淬火后": "55–60 HRC (water)", "为什么要回火": "未回火马氏体在服役中会开裂；回火以可控的硬度损失换回韧性" }, { "钢种": "4140", "Q&T 供货区间": "28–34 HRC pre-hard", "仅淬火后": "55–60 HRC (oil)", "为什么要回火": "500–650 °C 高温回火形成回火索氏体——这是轴和齿轮通常规定的状态" } ] }, { "caption": "6061-T6 比 6061-O 强多少？", "columns": [ "合金与状态", "抗拉强度，MPa（ksi）", "屈服强度，MPa（ksi）", "伸长率（%）", "硬度（HB）", "来源" ], "rows": [ { "合金与状态": "6061-O", "抗拉强度，MPa（ksi）": "125 (18)", "屈服强度，MPa（ksi）": "55 (8)", "伸长率（%）": "25–27", "硬度（HB）": "30", "来源": "S7 / S8" }, { "合金与状态": "6061-T4 / T451", "抗拉强度，MPa（ksi）": "240 (35)", "屈服强度，MPa（ksi）": "145 (21)", "伸长率（%）": "22", "硬度（HB）": "65", "来源": "S7 / S8" }, { "合金与状态": "6061-T6 / T651", "抗拉强度，MPa（ksi）": "310 (45)", "屈服强度，MPa（ksi）": "276 (40)", "伸长率（%）": "12–15", "硬度（HB）": "95", "来源": "S7 / S8" } ] }, { "caption": "6061-T651 比 6061-T6 强吗？", "columns": [ "状态", "工艺", "力学差异", "适用标准", "来源" ], "rows": [ { "状态": "O", "工艺": "完全退火——加热后缓慢冷却到最软状态", "力学差异": "强度最低，成形性最好", "适用标准": "ISO 2107; ASTM B209/B221", "来源": "S14 / S19 / S7" }, { "状态": "T4", "工艺": "固溶处理后，在室温自然时效", "力学差异": "强度中等，仍可成形", "适用标准": "ISO 2107; ASTM B209/B221", "来源": "S14 / S15 / S7" }, { "状态": "T6", "工艺": "固溶处理后，人工时效到峰值强度", "力学差异": "该合金的最高强度", "适用标准": "ISO 2107; ASTM B209/B221", "来源": "S14 / S15 / S7" }, { "状态": "T651", "工艺": "T6 加 1–3% 拉伸，在时效前去应力", "力学差异": "强度与 T6 相同；加工时尺寸稳定性更好", "适用标准": "ISO 2107; ASTM B209/B221", "来源": "S14 / S7 / S24" }, { "状态": "T73", "工艺": "固溶处理后，进行两级过时效", "力学差异": "强度低于 T6；抗应力腐蚀性能好得多；主要用于 7xxx 系", "适用标准": "AMS 4078; ASTM B209; GB/T 3880", "来源": "S9 / S2" } ] }, { "caption": "T73 是什么状态，什么时候该选它？", "columns": [ "适用口径", "抗拉强度（MPa）", "屈服强度（MPa）", "伸长率（%）", "硬度", "来源" ], "rows": [ { "适用口径": "7075-T73 — ASM Handbook typical (bar / forging reference)", "抗拉强度（MPa）": "505", "屈服强度（MPa）": "435", "伸长率（%）": "13", "硬度": "—", "来源": "S1 / S2" }, { "适用口径": "7075-T73 — ASTM B209 / AMS 4078 plate, by thickness (spec)", "抗拉强度（MPa）": "460–475", "屈服强度（MPa）": "385–390", "伸长率（%）": "5–8", "硬度": "126–140 HB", "来源": "S9" }, { "适用口径": "7075-T6 — typical, for comparison", "抗拉强度（MPa）": "572 (83 ksi)", "屈服强度（MPa）": "503 (73 ksi)", "伸长率（%）": "—", "硬度": "—", "来源": "S7" } ] }, { "caption": "17-4PH 最强的标准时效状态是哪一个？", "columns": [ "状态", "时效温度 / 时间", "抗拉强度最小值，MPa（ksi）", "屈服强度最小值，MPa（ksi）", "伸长率最小值（%）", "硬度", "夏比 V 型缺口（ft-lb）", "来源" ], "rows": [ { "状态": "H900", "时效温度 / 时间": "482 °C (900 °F) / 1 h", "抗拉强度最小值，MPa（ksi）": "1,310 (190)", "屈服强度最小值，MPa（ksi）": "1,170 (170)", "伸长率最小值（%）": "10", "硬度": "≥40 HRC (typical 44)", "夏比 V 型缺口（ft-lb）": "10–15 (low)", "来源": "S3 / S23" }, { "状态": "H1025", "时效温度 / 时间": "552 °C (1,025 °F) / 4 h", "抗拉强度最小值，MPa（ksi）": "1,070 (155)", "屈服强度最小值，MPa（ksi）": "1,000 (145)", "伸长率最小值（%）": "12", "硬度": "≥35 HRC (typical 38)", "夏比 V 型缺口（ft-lb）": "35–45 (moderate)", "来源": "S3 / S23" }, { "状态": "H1150", "时效温度 / 时间": "621 °C (1,150 °F) / 4 h", "抗拉强度最小值，MPa（ksi）": "930 (135)", "屈服强度最小值，MPa（ksi）": "725 (105)", "伸长率最小值（%）": "16", "硬度": "28–33 HRC (typical 33)", "夏比 V 型缺口（ft-lb）": "60–80 (high)", "来源": "S3 / S23" } ] }, { "caption": "17-4PH 哪个状态的韧性最高？", "columns": [ "状态", "夏比 V 型缺口（ft-lb）", "伸长率（%）", "硬度", "最适合" ], "rows": [ { "状态": "H900", "夏比 V 型缺口（ft-lb）": "10–15 (low)", "伸长率（%）": "10", "硬度": "≥40 HRC", "最适合": "最高强度、无冲击或低温要求的零件" }, { "状态": "H1025", "夏比 V 型缺口（ft-lb）": "35–45 (moderate)", "伸长率（%）": "12", "硬度": "≥35 HRC", "最适合": "通用平衡状态" }, { "状态": "H1150", "夏比 V 型缺口（ft-lb）": "60–80 (high)", "伸长率（%）": "16", "硬度": "28–33 HRC", "最适合": "面向冲击和低温的零件；也是符合 NACE 的选择" } ] }, { "caption": "17-4PH 能用于 NACE 酸性气体工况吗？", "columns": [ "状态", "规范硬度", "NACE MR0175 状态", "备注" ], "rows": [ { "状态": "H900", "规范硬度": "≥40 HRC (typical 44)", "NACE MR0175 状态": "Not qualified", "备注": "远超 33 HRC 的酸性工况硬度上限" }, { "状态": "H1025", "规范硬度": "≥35 HRC (typical 38)", "NACE MR0175 状态": "Conditional", "备注": "仅在逐炉验证实际硬度不超过 33 HRC 时可用" }, { "状态": "H1150", "规范硬度": "28–33 HRC (typical 33)", "NACE MR0175 状态": "Compliant", "备注": "酸性气体工况的标准选择" } ] } ] }