Propiedades generales de los aceros para herramientas
Tabla de referencia de los principales grados de acero para herramientas AISI, que abarca la resistencia al desgaste, la tenacidad, la dureza en caliente, la dureza de trabajo habitual, la profundidad de endurecimiento, el tamaño de grano y la dureza después del endurecimiento. Las clasificaciones son comparaciones relativas en una escala del 1 (bajo) al 9 (alto) y constituyen un punto de partida práctico para seleccionar un grado para una aplicación de herramientas específica.
| Calificación | Tener puesto (b) | Tenacidad (do) | dureza caliente | Dureza laboral, HRC | Profundidad (d) | Tamaño del grano (Pastor) | Superficie HRC | Centro HRC |
|---|---|---|---|---|---|---|---|---|
| Aceros rápidos de molibdeno | ||||||||
| M1 | 7 | 3 | 8 | 63–65 | D | 9½ | 64–66 | 64–66 |
| M2 | 7 | 3 | 8 | 63–65 | D | 9½ | 64–66 | 64–66 |
| M3, clase 1 | 8 | 3 | 8 | 63–66 | D | 9½ | 64–66 | 64–66 |
| M3, clase 2 | 8 | 3 | 8 | 63–66 | D | 9½ | 64–66 | 64–66 |
| M4 | 9 | 3 | 8 | 63–66 | D | 9½ | 65–67 | 65–67 |
| M7 | 8 | 3 | 8 | 63–66 | D | 9½ | 64–66 | 64–66 |
| M10 | 7 | 3 | 8 | 63–65 | D | 9½ | 64–66 | 64–66 |
| M30 | 7 | 2 | 8 | 63–65 | D | 9½ | 64–66 | 64–66 |
| M33 | 8 | 1 | 9 | 63–65 | D | 9½ | 64–66 | 64–66 |
| M34 | 8 | 1 | 9 | 63–65 | D | 9½ | 64–66 | 64–66 |
| M35 | 7 | 2 | 8 | 63–65 | D | 9½ | 64–66 | 64–66 |
| M36 | 7 | 1 | 9 | 63–65 | D | 9½ | 64–66 | 64–66 |
| M41 | 8 | 1 | 9 | 66–70 | D | 9½ | 63–65 | 63–65 |
| M42 | 8 | 1 | 9 | 66–70 | D | 9½ | 63–65 | 63–65 |
| M43 | 8 | 1 | 9 | 66–70 | D | 9½ | 63–65 | 63–65 |
| M44 | 8 | 1 | 9 | 66–70 | D | 9½ | 63–65 | 63–65 |
| M46 | 8 | 1 | 9 | 66–69 | D | 9½ | 63–65 | 63–65 |
| M47 | 8 | 1 | 9 | 66–70 | D | 9½ | 63–65 | 63–65 |
| Aceros intermedios de alta velocidad | ||||||||
| M50 | 6 | 3 | 6 | 61–63 | D | 8½ | 63–65 | 63–65 |
| M52 | 6 | 3 | 6 | 62–64 | D | 8½ | 63–65 | 63–65 |
| Aceros de tungsteno de alta velocidad | ||||||||
| T1 | 7 | 3 | 8 | 63–65 | D | 9½ | 64–66 | 64–66 |
| T2 | 8 | 3 | 8 | 63–66 | D | 9½ | 65–67 | 65–67 |
| T4 | 7 | 2 | 8 | 63–65 | D | 9½ | 63–66 | 63–66 |
| T5 | 7 | 1 | 9 | 63–65 | D | 9½ | 64–66 | 64–66 |
| T6 | 8 | 1 | 9 | 63–65 | D | 9½ | 64–66 | 64–66 |
| T8 | 8 | 2 | 8 | 63–65 | D | 9½ | 64–66 | 64–66 |
| T15 | 9 | 1 | 9 | 64–68 | D | 9½ | 65–68 | 65–68 |
| Aceros al cromo para trabajo en caliente | ||||||||
| H10 | 3 | 9 | 6 | 39–56 | D | 8 | 52–59 | 52–59 |
| H11 | 3 | 9 | 6 | 38–55 | D | 8 | 53–55 | 53–55 |
| H12 | 3 | 9 | 6 | 38–55 | D | 8 | 53–55 | 53–55 |
| H13 | 3 | 9 | 6 | 40–53 | D | 8 | 51–54 | 51–54 |
| H14 | 4 | 6 | 7 | 40–54 | D | 8 | 53–57 | 53–56 |
| H19 | 5 | 6 | 7 | 40–55 | D | 8½ | 48–57 | 48–57 |
| Aceros de tungsteno para trabajo en caliente | ||||||||
| H21 | 4 | 6 | 8 | 40–55 | D | 9 | 45–63 | 45–63 |
| H22 | 5 | 5 | 8 | 36–54 | D | 9 | 48–56 | 48–56 |
| H23 | 5 | 5 | 8 | 38–48 | D | 7 | 34–40 | 34–40 |
| H24 | 5 | 5 | 8 | 40–55 | D | 9 | 52–56 | 52–56 |
| H25 | 4 | 6 | 8 | 35–45 | D | 9 | 33–46 | 33–46 |
| H26 | 6 | 4 | 8 | 50–58 | D | 9 | 51–59 | 51–59 |
| Aceros para trabajo en caliente con molibdeno | ||||||||
| H42 | 6 | 4 | 7 | 45–62 | D | 8½ | 54–62 | 54–62 |
| Aceros de aleación media para trabajo en frío, endurecibles al aire. | ||||||||
| A2 | 6 | 4 | 5 | 57–62 | D | 8½ | 63–65 | 63–65 |
| A3 | 7 | 3 | 5 | 58–63 | D | 8½ | 63–65 | 63–65 |
| A4 | 5 | 4 | 4 | 54–62 | D | 8½ | 61–63 | 61–63 |
| A5 | 5 | 4 | 4 | 54–60 | D | 8½ | 60–62 | 60–62 |
| A6 | 4 | 5 | 4 | 54–60 | D | 8½ | 60–62 | 60–62 |
| A7 | 9 | 1 | 6 | 58–66 | D | 8½ | 64–66 | 64–66 |
| A8 | 4 | 8 | 6 | 48–57 | D | 8 | 60–62 | 60–62 |
| A9 | 4 | 8 | 6 | 40–56 | D | 8 | 55–57 | 55–57 |
| A10 | 3 | 3 | 3 | 55–62 | D | 8 | 60–63 | 60–63 |
| Aceros de alto contenido de carbono y cromo para trabajo en frío | ||||||||
| D2 | 8 | 2 | 6 | 58–64 | D | 7½ | 61–64 | 61–64 |
| D3 | 8 | 1 | 6 | 58–64 | D | 7½ | 64–66 | 64–66 |
| D4 | 8 | 1 | 6 | 58–64 | D | 7½ | 64–66 | 64–66 |
| D5 | 8 | 2 | 7 | 58–63 | D | 7½ | 61–64 | 61–64 |
| D7 | 9 | 1 | 6 | 58–66 | D | 7½ | 64–68 | 64–68 |
| Aceros para trabajo en frío endurecibles con aceite | ||||||||
| O1 | 4 | 3 | 3 | 57–62 | M | 9 | 61–64 | 59–61 |
| O2 | 4 | 3 | 3 | 57–62 | M | 9 | 61–64 | 59–61 |
| O6 | 3 | 3 | 2 | 58–63 | M | 9 | 65–67 | 50–55 |
| O7 | 5 | 3 | 3 | 58–64 | M | 9 | 61–64 | 59–61 |
| Aceros resistentes a los golpes | ||||||||
| S1 | 4 | 8 | 5 | 50–58 | M | 8 | 55–58 | 55–58 |
| S2 | 2 | 8 | 2 | 50–60 | M | 8 | 61–63 | 56–60 |
| S5 | 2 | 8 | 3 | 50–60 | M | 9 | 61–63 | 58–62 |
| S6 | 2 | 8 | 3 | 50–56 | M | 8 | 56–58 | 56–58 |
| S7 | 3 | 8 | 5 | 47–57 | D | 8 | 59–61 | 59–61 |
| Aceros de baja aleación para usos especiales | ||||||||
| L2 | 1 | 7 | 2 | 45–62 | M | 8½ | 56–62 | 54–58 |
| L6 | 3 | 6 | 2 | 45–62 | M | 8 | 58–63 | 58–62 |
| Aceros para moldes con bajo contenido de carbono | ||||||||
| Para cavidades con buje y/o carburizadas | ||||||||
| P2 (mi) | 1(mi) | 9 | 2(mi) | 58–64 (mi) | S | … | 62–65 (a) | 15–21 |
| P3 (mi) | 1(mi) | 9 | 2(mi) | 58–64 (mi) | S | … | 62–64 (a) | 15–21 |
| P4 (mi) | 1(mi) | 9 | 4(mi) | 58–64 (mi) | M | … | 62–65 (a) | 33–35 |
| P5 (mi) | 1(mi) | 9 | 2(mi) | 50–64 (mi) | S | … | 62–65 (a) | 20–25 |
| P6 (mi) | 1(mi) | 9 | 3(mi) | 58–61 (mi) | M | … | 60–62 (a) | 35–37 |
| Para cavidades mecanizadas | ||||||||
| P20 (mi) | 1(mi) | 8 | 2(mi) | 30–50 | M | 7½ | 52–54 | 45–50 |
| P21 | 1 | 8 | 4 | 36–39 (mi) | D | … | 22–26 | 22–26 |
| Aceros para herramientas endurecibles mediante agua | ||||||||
| W1 | 2–4 | 3–7 | 1 | 58–65 | S | 9 | 65–67 | 38–43 |
| W2 | 2–4 | 3–7 | 1 | 58–65 | S | 9 | 65–67 | 38–43 |
| W5 | 3–4 | 3–7 | 1 | 58–65 | S | 9 | 65–67 | 38–43 |
Notas y referencias
- (a) La calificación se basa en una escala del 1 (bajo) al 9 (alto).
- (b) La resistencia al desgaste aumenta con el incremento del contenido de carbono.
- (do) La tenacidad disminuye al aumentar el contenido de carbono y la profundidad de endurecimiento.
- (d) S, poco profundo; M, medio; y D, profundo.
- (mi) Después de la carburación.

Módulo de elasticidad de los aceros para herramientas
A efectos prácticos, el módulo de elasticidad de todos los aceros para herramientas en todas las condiciones es aproximadamente 210 GPa (30 × 106 psi) a temperatura ambiente. Disminuye uniformemente hasta aproximadamente 185 GPa (27 × 106 psi) a 260 °C (500 °F) y aproximadamente 150 GPa (22 × 106 psi) a 540 °C (1000 °F).
Resistencia al desgaste
Wear resistance increases with carbon content. At a given hardness, however, it may vary widely depending on the wear mechanism and heat treatment used. Steels with similar hardness can behave very differently under identical wear conditions. The grades that resist wear best are also the hardest to machine, and the machinability rating chart puts a number on that trade-off.
Resistencia y pruebas
At maximum hardness, most tool steels are brittle, so tensile testing rarely gives reliable strength values. Compression, bending and torsion tests are more useful; torsion impact testing gives reproducible data on the effect of composition and heat treatment, particularly for drills and tools loaded in torsion. Where toughness and wear resistance pull in opposite directions, selection by application is the faster route to a grade.
Nota sobre el alcance del suministro y la referencia técnica
Aobo Steel supplies tool steel in round bar and plate form, in annealed condition. Hardening, quenching and tempering are performed by the customer’s heat-treatment facility. The tool steel heat treatment guide covers austenitizing temperatures, soak times and tempering windows for these grades.
Las clasificaciones de propiedades y los datos de dureza que se incluyen en esta referencia son comparaciones relativas recopiladas del Manual ASM, Volumen 1, Tabla 13. El rendimiento real depende del tratamiento térmico, el tamaño de la sección, la geometría de la herramienta y las condiciones de servicio. Verifique siempre las propiedades finales y los procedimientos de tratamiento térmico con su centro de tratamiento térmico.
Páginas de referencia relacionadas
Tool steel composition chart · Tabla de dureza en caliente del acero para herramientas · Temperaturas de endurecimiento y revenido · Machinability ratings · Selection by application · Grade comparison and equivalents · Calculadora de conversión de dureza · Guía de tratamiento térmico del acero para herramientas · Tool steel thermal conductivity chart
Fuente: Manual ASM, Volumen 1 — Propiedades y selección: Hierros, aceros y aleaciones de alto rendimiento, Tabla 13 “Propiedades generales de los aceros para herramientas” (datos para los grados marcados con “e” después de la carburación). Datos de referencia para comparación: verifique el tratamiento térmico final con el proveedor del grado.
