Acier à outils ASTM T4 / 1.3255 / S 18-1-2-5 / SKH3

AISI T4 tool steel is one of tungsten type high speed tool steel, which belongs to ASTM A600 specification, the standard for high speed tool steel materials.

Acier à outils ASTM T4 is similar to T1 Tool Steel materials, but with 4.25~5.75% cobalt added to increase heat resistance. The red hardness of T4 steel and the high temperature hardness is a little higher than T1 tool steel. AISI T4 tool steel is a deep hardening alloy capable of Rockwell C 64 hardness.

Otai Steel is one of the leading supplier of AISI/ASTM T4 tool steel high speed materials. We know the features of T4 high speed steel materials and different applications & your various applications. You have the T4 tool steel materials data below.

1.ASTM/AISI T4 Tool Steel Supply Range

Barre ronde en acier T4: diamètre 2mm - 200mm
Aciers T4 plats: épaisseur 2-20mm x largeur 10-100mm
Plaque d'acier T4: épaisseur 2-200mm x largeur 200-810mm
Finition de surface: noir, usiné grossièrement, tourné ou selon les exigences données.

2.Relevant Steel Specifications of AISI T4 High Speed Tool Steels

Pays	USA	Allemand	Japon
standard	ASTM A600	ISO 4957	JIS G4403
grades	T4 / T12004	S 18-1-2-5/1.3255	SKH3

3.AISI T4 Tool Steel and Equivalents’ Chemical Composition

ASTM A600	C		Mn		P	S	Si		Cr		V		W		Mo		Co
T4	0.70	0.80	0.10	0.40	0.03	0.03	0.20	0.40	3.75	4.50	0.80	1.20	17.50	19.00	0.40	1.00	4.25	5.75
ISO 4957	C		Mn		P	S	Si		Cr		V		W		Mo		Co
S 18-1-2-5/1.3255	0.75	0.83	...	0.40	0.03	0.03	...	0.45	3.80	4.50	0.80	1.20	17.50	18.50	0.50	0.80	4.50	5.50
JIS G4403	C		Mn		P	S	Si		Cr		V		W		Mo		Co
SKH3	0.73	0.83	...	0.40	0.03	0.03	...	0.45	3.80	4.50	0.80	1.20	17.00	19.00	...	...	4.50	5.50

Propriétés mécaniques de l'acier à outils 4.High Speed ​​Steel T4

• Propriétés physiques des aciers à outils T4 haute vitesse
  • Physical properties (average values) at ambient temperature
  • Modulus of elasticity [103 x N/mm2]: 217
  • Density [g/cm3]: 8.70
  • Conductivité thermique [W / mK]: 19.0
  • Electric resistivity [Ohm mm2/m]: 0.65
  • Capacité thermique spécifique [J / gK]: 0.46

• Propriétés mécaniques de l'acier T-4

Propriétés	Métrique	Imperial
Module d'élasticité	GPU 190-210	27557-30458 ksi
Coefficient de Poisson	0.27-0.30	0.27-0.30

• Thermal Properties of T4 Tool Steels

Propriétés	Métrique	Imperial
Thermal expansion co-efficient	11.9 µm / m ° C	6.6 µin / in ° F

5: Forge des matériaux en acier à outils ASTM T4

Forging of T4 steel can be carried out from 850 to 1120°C (1775 to 2100°F).

• Preheat T4 steel material uniformly and slowly to 860-880°C.
• Increase the forging temperature up to 1050-1120°C.
• L'acier à outils T4 hss doit être refroidi très lentement après le forgeage.

Traitement thermique et propriétés de l'acier à outils 6.AISI / ASTM T4

• durcissement

Harden T4 high speed tool steel from a temperature of 1260-1290oC followed by oil, air quenching or warm bath at 550oC. Hardness after quenching is 63-66 HRC.

• recuit

T4 steel should be annealed after hot working. Increase the temperature of T4 high speed steel to 860°C(Max220°C per hour). Hold at the temperature and then cool slowly with the furnace. The annealed hardness achieved should be below HB255.

• Tempérer

Tempering temperature: 2x 560-580oC. Hardness after tempering is 64-65 HRC.

7.Applications of ASTM / AISI T4 Tool Steel

AISI T4 high speed tool steels are widely used as cutting tools, broaches and cold extrusion punches, turning, planing and milling cutters for roughing work.

Les applications typiques sont:

• Perceuses,
• Fraises,
• Outils de coupe de fil,
• Outils de moletage,
• Poinçons d'extrusion à froid
• Broches etc.

Besides of ASTM/AISI T4 high speed tool steel materials, we are also capable of supplying T1 high speed steel, T10 tool steels, T15 tool steel etc. Just contact us for more details and latest price offer. If you have any questions, also leave a comment below.