Tool Steel Hardening and Tempering Chart (AISI M, T, H, D, A, O, S, P, L, F, W) | Aobo Steel
Dados de referência para aço ferramenta

Tool Steel Hardening and Tempering Chart

Recommended hardening and tempering practice for the principal AISI tool steels — preheat and austenitizing (hardening) temperatures, soak time, quenching medium and tempering temperature, grouped by steel family. Values are given in both °C and °F as printed in the source.

°C / °F both given 730-845 from–to range not specified (a)–(k) footnote O · A · S · W · B quench media
TipoRate of heatingEndurecimentoResfriamento
medium(um)
Temperatura de têmpera
Preheat temperatureHardening temperatureTime at temperature, min°C°F
°C°F°C°F
Aços rápidos com molibdênio
M1, M7, M10Rapidly from preheat730-8451350-15501175-12202150-2225 (b)2-5O, A, or S540-595 (c)1000-1100 (c)
M2Rapidly from preheat730-8451350-15501190-12302175-2250 (b)2-5O, A, or S540-595 (c)1000-1100 (c)
M3, M4, M30, M33, M34, M35Rapidly from preheat730-8451350-15501205-1230 (b)2200-2250 (b)2-5O, A, or S540-595 (c)1000-1100 (c)
M36Rapidly from preheat730-8451350-15501220-1245 (b)2225-2275 (b)2-5O, A, or S540-595 (c)1000-1100 (c)
M41Rapidly from preheat730-8451350-15501190-1215 (b)2175-2220 (b)2-5O, A, or S540-595 (d)1000-1100 (d)
M42Rapidly from preheat730-8451350-15501190-1210 (b)2175-2210 (b)2-5O, A, or S510-595 (d)950-1100 (d)
M43Rapidly from preheat730-8451350-15501190-1215 (b)2175-2220 (b)2-5O, A, or S510-595 (d)950-1100 (d)
M44Rapidly from preheat730-8451350-15501200-1225 (b)2190-2240 (b)2-5O, A, or S540-625 (d)1000-1160 (d)
M46Rapidly from preheat730-8451350-15501190-1220 (b)2175-2225 (b)2-5O, A, or S525-565 (d)975-1050 (d)
M47Rapidly from preheat730-8451350-15501175-1200 (b)2150-2200 (b)2-5O, A, or S525-595 (d)975-1100 (d)
M48Rapidly from preheat730-8451350-15501175-1200 (b)2150-2200 (b)2-5O, A, or S540-595 (d)1000-1100 (d)
M62Rapidly from preheat730-8451350-15501175-1200 (b)2150-2200 (b)2-5O, A, or S540-595 (d)1000-1100 (d)
Aços rápidos de tungstênio
T1, T2, T4, T8Rapidly from preheat815-8701500-16001260-1300 (b)2300-2375 (b)2-5O, A, or S540-595 (c)1000-1100 (c)
T5, T6Rapidly from preheat815-8701500-16001275-1300 (b)2325-2375 (b)2-5O, A, or S540-595 (c)1000-1100 (c)
T15Rapidly from preheat815-8701500-16001205-1260 (b)2200-2300 (b)2-5O, A, or S540-650 (d)1000-1200 (d)
Aços rápidos intermediários
M50Rapidly from preheat730-8451350-15501095-11202000-20502-5O, A, or S525-595975-1100
M52Rapidly from preheat730-8451350-15501120-11752050-21502-5O, A, or S525-595975-1100
Aços cromados para trabalho a quente
H10Moderately from preheat81515001010-10401850-190015-40 (e)A540-6501000-1200
H11, H12Moderately from preheat8151500995-10251825-187515-40 (e)A540-6501000-1200
H13Moderately from preheat8151500995-10401825-190015-40 (e)A540-6501000-1200
H14Moderately from preheat81515001010-10651850-195015-40 (e)A540-6501000-1200
H19Moderately from preheat81515001095-12052000-22002-5A or O540-7051000-1300
Aços para trabalho a quente com tungstênio
H21, H22Rapidly from preheat81515001095-12052000-22002-5A or O595-6751100-1250
H23Rapidly from preheat84515501205-12602200-23002-5O650-8151200-1500
H24Rapidly from preheat81515001095-12302000-22502-5O565-6501050-1200
H25Rapidly from preheat81515001150-12602100-23002-5A or O565-6751050-1250
H26Rapidly from preheat87016001175-12602150-23002-5O, A or S565-6751050-1250
Aços para trabalho a quente com molibdênio
H41, H43Rapidly from preheat730-8451350-15501095-11902000-21752-5O, A or S565-6501050-1200
H42Rapidly from preheat730-8451350-15501120-12202050-22252-5O, A or S565-6501050-1200
Aços para trabalho a frio com alto teor de carbono e cromo
D1, D5Very slowly8151500980-10251800-187515-45A205-540400-1000
D3Very slowly8151500925-9801700-180015-45O205-540400-1000
D4Very slowly8151500970-10101775-185015-45A205-540400-1000
D7Very slowly81515001010-10651850-195030-60A150-540300-1000
Medium-alloy, air-hardening, cold-work steels
A2Slowly7901450925-9801700-180020-45A175-540350-1000
A3Slowly7901450955-9801750-180025-60A175-540350-1000
A4Slowly6751250815-8701500-160020-45A175-425350-800
A6Slowly6501200830-8701525-160020-45A150-425300-800
A7Very slowly8151500955-9801750-180030-60A150-540300-1000
A8Slowly7901450980-10101800-185020-45A175-595350-1100
A9Slowly7901450980-10251800-187520-45A510-620950-1150
A10Slowly6501200790-8151450-150030-60A175-425350-800
Aços para trabalho a frio com têmpera em óleo
O1Slowly6501200790-8151450-150010-30O175-260350-500
O2Slowly6501200760-8001400-14755-20O175-260350-500
O6Slowly790-8151450-150010-30O175-315350-600
O7Slowly6501200790-830
845-885
W: 1450-1525
O: 1550-1625
10-30O or W175-290350-550
Aços resistentes a choques
S1Slowly900-9551650-175015-45O205-650400-1200
S2Slowly650 (f)1200 (f)845-9001550-16505-20B or W175-425350-800
S5Slowly7601400870-9251600-17005-20O175-425350-800
S7Slowly650-7051200-1300925-9551700-175015-45A or O205-620400-1150
Mold steels
P2900-925 (g)1650-1750 (g)830-845 (h)1525-1550 (h)15O175-260350-500
P3900-925 (g)1650-1700 (g)800-830 (h)1475-1525 (h)15O175-260350-500
P4970-995 (g)1775-1825 (g)970-995 (h)1775-1825 (h)15A175-480350-900
P5900-925 (g)1650-1700 (g)845-870 (h)1550-1600 (h)15O or W175-260350-500
P6900-925 (g)1650-1700 (g)790-815 (h)1450-1500 (h)15A or O175-230350-450
P20870-900 (h)1600-1650 (h)815-8701500-160015O480-595 (i)900-1100 (i)
P21 (j)SlowlyDo not preheat705-7301300-135060-180A or O510-550950-1025
Aços especiais de baixa liga
L2SlowlyW: 790-845
O: 845-925
W: 1450-1550
O: 1550-1700
10-30O or W175-540350-1000
L3SlowlyW: 775-815
O: 815-870
W: 1425-1500
1500-1600
10-30O or W175-315350-600
L6Slowly790-8451450-155010-30O175-540350-1000
Carbon-tungsten special-purpose steels
F1, F2Slowly6501200790-8701450-160015W or B175-260350-500
Water-hardening steels
W1, W2, W3Slowly565-650 (k)1050-1200 (k)760-8451400-155010-30B or W175-345350-650
  • (um) O, oil quench; A, air cool; S, salt bath quench; W, water quench; B, brine quench.
  • (b) When the high-temperature heating is carried out in a salt bath, the range of temperatures should be about 14 °C (25 °F) lower than given here.
  • (c) Double tempering recommended for not less than 1 h at temperature each time.
  • (d) Triple tempering recommended for not less than 1 h at temperature each time.
  • (e) Times apply to open furnace heat treatment. For pack hardening, a common rule is to heat 1.2 min per mm (30 min per in.) of cross section of the pack.
  • (f) Preferable for large tools to minimize decarburization.
  • (g) Carburizing temperature.
  • (h) Após a cementação.
  • (i) Carburized per case hardness.
  • (j) P21 is a precipitation-hardening steel having a thermal treatment that involves solution treating and aging rather than hardening and tempering.
  • (k) Recommended for large tools and tools with intricate sections.

Notas de mesa

For O7, L2 and L3 the source gives two hardening ranges: the C: value applies to water quenching and the O: value to oil quenching. O7’s hardening ranges are printed in the W/O order in the °F column.

Two printed values are corrected here, following cross-checks against the source’s own companion values: A6’s hardening temperature is printed “1525n-;1600” in the e-book and is given as 1525–1600 °F (matching the 830–870 °C range); S7’s tempering range is printed 205–260 °C, which does not match its own 400–1150 °F column, and is given as 205–620 °C (620 °C = 1150 °F), matching the parallel tables in Aços para ferramentas (Roberts & Krauss, 5th ed.) and Machinery’s Handbook.

The source table does not include D2 among the high-carbon, high-chromium cold-work steels; see the Guia de tratamento térmico de aço para ferramentas D2 for that grade.

Hardening temperatures are austenitizing temperatures for conventional heat treatment; the quenching medium letter codes are explained in footnote (a). These are reference ranges — confirm production practice with your heat treater, since furnace type, load and section size all shift the working schedule. When a cycle does go wrong, the causes and the corrections are listed in the heat treatment troubleshooting chart.

Source: ASM Handbook, Volume 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys, Table 9 “Hardening and tempering of tool steels” (10th ed.). Reference data for comparison — verify the applicable standard before ordering.