High Speed Steel

PM T-15

PM T-15 High Speed Steel Data Sheet

PM T-15 is a tungsten type super high speed steel containing high vanadium for excellent abrasion resistance and cobalt for good red hardness. PM T-15 is ideal for cutting difficult to machine materials where high frictional heat is present.


Chemical Composition

Carbon 1.60%
Manganese 0.30%
Chromium 4.00%
Cobalt 5.00%
Vanadium 4.90%
Tungsten 12.00%
Silicon 0.30%
Sulfur 0.06%

Typical Applications

Broaches Milling Cutters
Gear Hobs Spade Drills
Taps End Mills
Shaper Cutters


High Speed Steel Comparison Chart


Thermal Treatments

Preheat : 1500/1550F (820/845C), equalize, Second preheating stage at 1800/1850F (1010/1040C)recommended for vacuum or atmosphere hardening. equalize.

Austenize : 2125/2250F (1165/1235C), 30/45 minutes at temperature. Standard recommendation to achieve RC 66-68 after tempering is to use 2225/2250F (1220/1235C)

Quench : Salt, oil or atmosphere quench to 1000-1100F(540-595C), equalize, then air cool to below 125F(50C) or hand warm. Vacuum or atmosphere quench rate through 1850-1300F(1010-705C) range is critical to achieve optimum heat treat results.

Temper : 1000F (540C) minimum, hold 2 hours at temperature, air cool. Triple tempering is required if austenizing at 2000F (1095C) or above.

Cryogenic Treating : Refrigeration treatments may improve long term dimensional stability by transforming retained austenite. Refrigeration treatments should generally be performed after the first temper, and must be followed by a temper.

Hardening Data


Temperature2125F 2150F2175F2200F2225F2250F
°C°F(1165C)(1180C)(1190C)(1205C)(1220C)(1235C)
As Quenched

6766.56665.564.564
54010006565.56666.56767.5
OPTIMUM FOR MAXIMUM TOUGHNESS AND EFFECTIVE STRESS-RELIEVING
5501025
64.56565.56666.567
56510506464.56565.56666.5
59511006252.56363.56464.5
62011505758.559.560.56161.5
65012005455565757.558
NOTE A:
RESULTS MAY VARY WITH HARDENING METHOD AND SECTION SIZE. SALT OR OIL QUENCHING WILL GIVE MAXIMUM RESPONSE. VACUUM OR ATMOSPHERE COOLING MAY RESULT IN UP TO 1-2 HRC POINTS LOWER.
MINIMUM TIME AT
AUST TEMP (MINS)
101010555
MINIMUM NUMBER
OF TEMPERS (2 HRS)
333333

Surface Treatments

PM T-15 can be nitrided, steam tempered or titanium-nitride coated if desired. If the CVD TiN treatment is used, care is required in vacuum hardening.

Annealing

Heat to 1600F (870C), hold 2 hours, slow cool 30F (15C)/hour maximum) to 1000F (540C), then furnace or air cool.

Typical annealed hardness: 245/275 BHN.

Stress Relieving

Annealed Material: Heat to 1100/1300F(595/740C), hold two hours, cool in still air.
Hardened Material: Heat to 25F(15C) below original tempering temperature, hold two hours, cool in still air.

Welding

Welding of PM T-15 is generally not recommended due to the fine-grain microstructure produced by the PM process. If weld repair must be performed, use air hardening tool steel filler material.

Annealed Material:Preheat 1000/1100F(540/595C), maintain over 1000F(540C) during welding. Reanneal or temper 1550F(845C) 6 hours after welding.

Hardened Material: Preheat to 25F(15C) below original tempering temperature (1000F(540C) minimum). Maintain above 900F(480C) during welding. Cool to 150F(65C) after welding. Temper 25F(15C) below original tempering temperature. Minimum 1000F(540C)

Physical Properties

Modulus of Elasticity 31psix10(6) (221 GPa)
Density 0.296 lb/in3 (8193 kg/M3)
Thermal Conductivity 11.5 BTU/hr./ft./F 19 W/m/ °K)