5Cr3Mn1SiMo1V is a grade under the Chinese GB standard, representing a high-toughness, impact-resistant tool steel. Its equivalent steels include AISI/ASTM S7 in the United States and DIN W-Nr. 1.2355 in Germany.

1. Chemical Composition(GB/ 1299-2000)

C	Si	Mn	Cr	Mo	V	P	S
0.45-0.55%	0.20-1.00%	0.20-0.90%	3.00-3.50%	1.30-1.80%	≤0.35%	≤0.030%	≤0.030%

2. 5Cr3Mn1SiMo1V Steel Forging Process Specification

Item	Heating Temperature (°C)	Initial Forging Temp (°C)	Final Forging Temp (°C)	Cooling Method
Steel Ingot	1120 – 1150	1150 – 1200	900	Slow Cooling
Steel Billet	1150 – 1200	1000 – 1150	850	Slow Cooling

3. 5Cr3Mn1SiMo1V Steel Heat Treatment Process Specification

3.1 Preheating

Preliminary Heat Treatment Plan	Process Parameters
Isothermal Annealing after Forging	Heating Temp: 800-820°C, Soak: 2-3h, Isothermal Temp: 700-720°C, Soak: 3-5h, furnace cool to 550°C then air cool, Hardness after annealing ≤229 HBW
General Annealing after Forging	Heating Temp: 800-820°C, Soak: 2-3h, furnace cool to 550°C then air cool, Hardness after annealing ≤229 HRC

3.2 Quenching and Tempering

Quenching Specification			Tempering Specification
Quenching Temp (°C)	Cooling Method	Hardness HRC	Tempering Temp (°C)	Hardness HRC
940 – 955	Air or Oil Cooling	56	160 – 180	56 – 58

4. Mechanical Properties of 5Cr3Mn1SiMo1V

5Cr3Mn1SiMo1V steel is a high-impact-resistant tool steel. Its elevated chromium content enhances hardenability. Silicon and manganese improve strength and resistance to tempering. Molybdenum and vanadium refine the grain structure, further increasing hardenability and elevating the steel’s overall performance. Additionally, with a chromium content exceeding 2.5% by mass, this steel exhibits excellent resistance to hydrogen embrittlement and oxidation at moderate temperatures.

5. Applications

5Cr3Mn1SiMo1V steel exhibits high toughness and moderate oxidation resistance at elevated temperatures, making it suitable for manufacturing tools and dies that operate under high impact loads. It is also well-suited for producing hammer forging dies and similar applications.