How to Select Tool Steels
This page is a practical reference for selecting tool steels by application, working condition, and required properties.
- Find the tool application
- Identify the working condition
- Check the required property
- Compare suitable grades
- Confirm process limits
1. Property Ratings of Common Tool Steels
The following charts compare common tool steels by relative property ratings. These values are useful for comparison, but they are not absolute mechanical test values.
Final performance still depends on steel quality, heat treatment, section size, tool design, and actual service conditions.
Resistência à abrasão
M4, D2, and M2 have the highest abrasion-resistance ratings in this comparison.
Robustez
S7, H13, and S5 have the highest toughness ratings in this comparison.
Usinabilidade
O6 and O1 are easier to machine than high-wear-resistance grades such as D2, M2, and M4.
Moabilidade
H13, S7, and S5 are easier to grind, while D2, M2, and M4 are more difficult.
2. Tool Steel Selection by Application
The table below gives a starting point for selecting tool steel. It does not replace application testing or heat-treatment confirmation.
Need a faster application-based recommendation?
Use the Tool Steel Material Finder to select an application first and compare suitable Aobo Steel grades with replacement logic.
| Application / Tool | Working Condition | Main Required Property | General Grade | Higher-Performance Grade |
|---|---|---|---|---|
| Ferramentas de corte | Cortes leves, velocidades lentas | Wear resistance with acceptable grindability | O1, A2 | M2 |
| Ferramentas de corte | Cortes pesados, velocidades rápidas | Wear resistance and hot hardness | M2 | M4, T1, M42 |
| Ferramentas chatas | Metal cutting | Hot hardness and wear resistance | M2 | M4 |
| Broches | Metalworking | Wear resistance and hot hardness | M2 | M4 |
| Form cutters | Profile cutting | Wear resistance and hot hardness | M2 | M4 |
| Fresas | Continuous cutting | Hot hardness and edge wear resistance | M2 | M4 |
| Thread cutters | Thread cutting | Wear resistance and hot hardness | M2 | M4 |
| Woodworking cutters | Edge wear with regrinding requirement | Wear resistance and grindability | O1 | M2 |
| Cold shear blades | Light gauge stock | Wear resistance with moderate toughness | A2 | D2 |
| Cold shear blades | Heavy gauge stock | Impact resistance and cracking resistance | S5 | S7 |
| Lâminas de corte a quente | Hot cutting | Hot hardness and toughness | S7, A8 | H13, H21 |
| Paper knives | Edge wear | Resistência ao desgaste | D2 | M2, M4 |
| Rotary knives | Continuous cutting wear | Resistência ao desgaste | A8 | D2 |
| Chipper knives | Impact and edge wear | Toughness with wear resistance | A2, A8 | D2, M2 |
| Matrizes de corte | Cold work, short runs | Balanced wear resistance and machinability | O1, O6 | A2 |
| Matrizes de corte | Cold work, long runs | Wear resistance and dimensional stability | A2 | D2, M2 |
| Matrizes de dobra | Cold forming | Toughness and dimensional stability | O1, O6 | A2, D2 |
| Matrizes de cunhagem | High pressure cold work | Wear resistance and compressive strength | O1 | A2, D2 |
| Embossing dies | Cold pressure and surface detail | Wear resistance and dimensional stability | A2 | D2 |
| Matrizes de conformação a frio | General forming | Wear resistance with stability | O1 | A2, D2 |
| Hot forming dies | Hot work | Hot hardness and toughness | H13, S7 | H21 |
| Matrizes de extrusão a frio | High pressure and wear | Wear resistance with enough toughness | D2 | M2 |
| Hot extrusion dies for aluminum | Heat softening and thermal fatigue | Hot hardness and toughness | H13 | H11, H21 |
| Hot extrusion dies for copper and brass | Higher hot wear and thermal load | Hot hardness and thermal resistance | H13 | H21 |
| matrizes de fundição sob pressão | Thermal fatigue, heat checking, cracking | Hot work stability | H13 | Premium H13 / ESR H13 |
| Brass die casting dies | Higher hot wear | Hot hardness and heat resistance | H13 | H21 |
| Matrizes de forjamento a quente | Heat, impact, thermal fatigue | Toughness and hot hardness | H13, S7 | H21, H43 |
| Hot trimming dies | Hot impact and edge damage | Toughness and hot hardness | S7, H13 | H21 |
| Cold heading tools | Impact, pressure, wear | Toughness and wear resistance | A2, S7 | D2, M2 |
| Cold punches | Piercing, trimming, forming | Resistência ao desgaste e tenacidade | A2, S7 | D2, M2 |
| Heavy-duty punches | Shock-loaded punching | Toughness first | S5 | S7 |
| Draw punches | Drawing pressure and wear | Resistência ao desgaste e tenacidade | A2, D2 | M2 |
| Thread rolls | Surface pressure and wear | Resistência ao desgaste | D2 | M2 |
| Formando rolos | Rolling pressure and wear | Wear resistance and dimensional stability | O1, A2 | D2, D7 |
| Rolos de acionamento | Wear under contact pressure | Resistência ao desgaste | D2 | D7 |
| Wire drawing tools | Sliding wear and surface pressure | Resistência ao desgaste | D2 | M4 |
| Plug gauges | Wear and dimensional stability | Wear resistance and stability | A2 | D2 |
| Master hobs | Accuracy and wear resistance | Wear resistance and stability | S7 | A2, D2 |
| Cutting hobs | Cutting wear and heat | Hot hardness and wear resistance | M2 | T1 |
| Lathe tools | Cutting heat and wear | Dureza quente | M2 | M42 |
| Ferramentas de plaina | Cutting wear | Hot hardness and wear resistance | M2 | M4 |
| Ferramentas de modelagem | Cutting wear | Hot hardness and wear resistance | M2 | M4 |
| Alargadores | Cutting accuracy and wear | Wear resistance and hot hardness | M2 | M4 |
| Torneiras | Thread cutting wear | Wear resistance and hot hardness | O1 | M2 |
| Brocas | Cutting heat and edge wear | Hot hardness and wear resistance | M2 | M4 |
| Buchas de perfuração | Wear from repeated drilling | Resistência ao desgaste | S5 | A2 |
| Morre o freio | Bending pressure | Toughness and wear resistance | 4140 HT | A2 |
| Gripper dies, cold | Holding pressure and wear | Resistência ao desgaste e tenacidade | O1, S7 | A2, D2 |
| Gripper dies, hot | Hot gripping and wear | Hot hardness and toughness | S7, H13 | H21 |
| Swaging dies, cold | Impact and forming pressure | Toughness and wear resistance | S7 | D2 |
| Swaging dies, hot | Heat and impact | Hot hardness and toughness | H13, S7 | H21 |
| Matrizes de laminação | Wear and edge stability | Resistência ao desgaste | A2 | D2, M2 |
| Moldes de plástico | Machining, polishing, mold surface quality | Machinability and polishability | P20, H13 | 420, special mold steels |
| Impact tools | Repeated shock | Robustez | S5 | S7 |
| Battering tools, cold | Shock and breakage | Robustez | S5 | S7 |
| Ferramentas de ferreiro | Impact and heat | Robustez | S5 | S7 |
| Ferramentas para caldeiraria | Impact work | Robustez | S5 | S7 |
| Chisels, cold working | Impact and edge chipping | Robustez | S5 | S7 |
| Chisels, hot working | Heat and impact | Toughness and hot hardness | S7 | M2 |
| Ferramentas pneumáticas | Repeated impact | Robustez | S5 | S7 |
| Rompedores de concreto | Severe impact | Robustez | S5 | S7 |
| Pontas de chave de fenda | Torsion and impact | Robustez | S5 | S7 |
| Caramanchões | Support and wear | Toughness and dimensional stability | O1, O6 | A2, D2 |
| Pinças | Holding pressure and wear | Toughness and wear resistance | O1 | S5, S7 |
| Mandíbulas de Chuck | Holding pressure and impact | Robustez | S5 | S7 |
3. Selection Notes
| Selection Note | Meaning |
|---|---|
| If the tool wears gradually, start by comparing wear-resistant grades. | D2, M2, M4, and related grades are common starting points for abrasive wear. |
| If the tool chips, cracks, or breaks suddenly, check toughness before increasing hardness. | S7, S5, H13, and other tougher grades may be more suitable for shock-loaded tools. |
| If the tool works under heat, room-temperature hardness is not enough. | Hot hardness and resistance to softening become more important. |
| If the tool requires frequent sharpening, grindability affects maintenance cost. | High-wear-resistance grades may be harder to grind. |
| If the tool is large or complex, heat-treatment distortion must be considered. | Air-hardening grades are often used where dimensional stability is important. |
| If the production run is short, the highest-performance grade may not be economical. | Machinability and material cost may be more important for short-run tooling. |
| If the production run is long, higher wear resistance may reduce total cost. | More expensive grades can be justified when they reduce downtime and replacement frequency. |
4. Final Technical Check Before Grade Selection
| Check Item | Confirm Before Selection |
|---|---|
| Tool function | Cutting, shearing, forming, drawing, extrusion, rolling, impact, molding |
| Working temperature | Room temperature, warm work, hot work |
| Main failure mode | Wear, chipping, cracking, softening, deformation, distortion |
| Load level | Light, medium, heavy, shock-loaded |
| Production volume | Short run, medium run, long run |
| Section size | Small tool, thick section, large die block |
| Heat treatment target | Required hardness, toughness, distortion control |
| Finishing requirement | Machining, grinding, polishing, sharpening |
| Cost target | Material cost, machining cost, maintenance cost, cost per part |
Tool Steel Supply Support
Aobo Steel supplies common tool steel grades for bulk orders, including D2, A2, S7, H13, H11, O1, and M2.
