T1 1.3355 HS18-0-1 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.
Applications of ASTM/AISI T1 Tool Steel
- Broaches
- Drills
- Hobs
- Knurling Tools
- Lathe Tools
- Milling Cutters
- Nut Piercers
- Planer Tools
- Reamers
- Shaving Tools
- Taps
- Thread Cutting Tools
Equivalent grades of steel HS18-0-1 (1.3355)
EU EN | USA – | Germany DIN,WNr | Japan JIS | France AFNOR | England BS | China GB | Sweden SS | Poland PN | Austria ONORM | Russia GOST |
HS18-0-1 | T1 | HS18-0-1 | SKH2 | Z80WCV18-04-01 | BT1 | W18Cr4V | 2750 | SW18 | S200 | R18 |
Chemical composition % of steel HS18-0-1 (1.3355): EN 4957-2000
C | Si | Mn | P | S | Cr | W | V |
0.73 – 0.83 | max 0.45 | max 0.4 | max 0.03 | max 0.03 | 3.8 – 4.5 | 17.2 – 18.7 | 1 – 1.2 |
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 |