What is T1 High Speed tool steel ?
AISI/ASTM T1 tool steel is one of the original tungsten high speed steels, although all tungsten steel grades are used to a limited extent because of the cost and questionable availability of tungsten. Of the T group steels, the general purpose T1 tool steels and the high-vanadium-cobalt T15 are most commonly used.
T1 high speed steel is an air or oil hardening tool steel which has good comprehensive performance. HSS T1 tool steel has a high hardness (HRC62~66), strength, toughness and heat resistance, which is an excellent cutting tool material. T-1 tool steel grade is on the whole used for turning, planning & slotting instruments, tapes, twist drill, threading dies, profile slicing instruments, broaching instruments & reamers.
Generally, high speed steels are divided into three groups:
- Those bearing the symbol T where tungsten is the major alloying element;
- Those bearing the symbol M indicating that molybdenum are the principal alloying element;
- A group of more highly alloyed steels that is capable of attaining unusually high hardness values.
Here we have tool steel type T-1 with the chemical composition, physical, mechanical and thermal properties and other equivalents of T1 tool steels. Except T1 hss tool steel, we are also able to supply T2, T10, T-15 high speed steel etc.
1.High Speed T1 Tool Steel Supply Range
T1 Steel Round Bar: diameter 2mm – 200mm
T1 Steel Flat: thickness 2-20mm x width 10-100mm
T1 Steel Plate: thickness 2-200mm x width 200-610mm
Surface Finish: Black, Rough Machined, Turned or as per given requirements.
2.Relevant Steel Specification of AISI T1 High Speed Tool Steels
| Country | USA | German | Japan |
| Standard | ASTM A600 | DIN EN ISO 4957 | JIS G4403 |
| Grades | T1 | HS18-0-1/1.3355 | SKH2 |
3.AISI T1 Tool Steel and Equivalents’ Chemical Composition Properties
| ASTM A600 | C | Mn | P | S | Si | Cr | V | Mo | W | Co | ||||||||
| T1 | 0.62 | 0.80 | 0.10 | 0.40 | 0.03 | 0.03 | 0.20 | 0.40 | 3.75 | 4.50 | 0.90 | 1.30 | … | … | 17.25 | 18.75 | … | … |
| DIN ISO 4957 | C | Mn | P | S | Si | Cr | V | Mo | W | Co | ||||||||
| HS18-0-1/1.3355 | 0.73 | 0.85 | … | … | … | … | … | 0.65 | 3.60 | 4.50 | 1.00 | 1.20 | … | … | 17.20 | 18.70 | … | … |
| JIS G4403 | C | Mn | P | S | Si | Cr | V | Mo | W | Co | ||||||||
| SKH2 | 0.73 | 0.83 | … | 0.40 | 0.03 | 0.03 | … | 0.45 | 3.80 | 4.50 | 1.00 | 1.20 | … | … | 17.20 | 18.70 | … | … |
4.High Speed Steel T1 Tool Steel Mechanical Properties
- Physical Properties of HSS T-1 Steels
| Properties | Metric | Imperial |
| Density | 8.67 g/cm3 | 0.313 lb/in3 |
- Mechanical Properties of T-1 Steel
| Properties | Metric | Imperial |
| Hardness, Rockwell C | 63.0 – 65.0 | 63.0 – 65.0 |
| Poisson’s ratio | 0.27-0.30 | 0.27-0.30 |
| Elastic modulus | 190-210 GPa | 27557-30457 ksi |
- Thermal Properties of T1 Tool Steel
| Properties | Conditions | ||
| T (°C) | Treatment | ||
| Thermal expansion | 9.7 x 10-6/ºC | 20-200 more | – |
| Thermal conductivity | 19.9 x W/m-K | 100 more | – |
- Preheat T1 high speed steel uniformly and slowly to 850-880°C.
- Increase the forging temperature for T-1 tool steel until 1050-1130°C.
- T1 hss tool steel should be cooled very slowly after forging.
6.AISI/ASTM T1 Tool Steel Heat Treatment and Properties
| Treatment | Temperature Range | Cooling/Quenching | Notes |
| Forging | 1700-2100° F | Slow. | Cool slowly in dry sand or in other insulating media. |
| Annealing | 1600-1650° F | Cool slowly at a rate of 35° F per hour to 1000° F. | For best results, insulating media is desirable. Hold at temperature for 2 hours. |
| Stress Relieving | 1100-1300° F | Cool slowly | Stress relieve after rough machining |
| Preheating | 1500-1550° F | Preheat time in furnace is ¾ Hr. per inch of thickness. Heating up to temperature as slow as possible. | |
| Hardening | 2325-2375° F (furnace) | Quench in air or warm oil. To minimize quenching strains, quench in salt at 1000° F | For maximum wear resistance, harden at 2375° F. For maximum toughness and high hardness, harden at 2275° F. |
| 2275-2350° F (salt bath) | |||
| Tempering | 1022 ° F-1058 ° F | Temper T1 high-speed steel immediately after quenching. Hold for at least two hours | Double tempering is recommended. The usual tempering time is 2+2 hours. Recommended temperature is 1000-1075° F for cutting tools. 1100-1200° F for shock tools |
7.Applications of ASTM/AISI T1 Tool Steel
Generally, high speed steels are used for machining at high speeds. HSS T1 steel materials are widely used for:
- Broaches
- Drills
- Hobs
- Knurling Tools
- Lathe Tools
- Milling Cutters
- Nut Piercers
- Planer Tools
- Reamers
- Shaving Tools
- Taps
- Thread Cutting Tools
We are capable of supply top quality T1 tool steel high speed also in good price, you could send us enquiries of T1 steel and request the latest offer. And leave a comment if there are any queries.