An Exploration of 7Cr17MoV Stainless Steel
Originating from the Chinese GB standard, 7Cr17MoV constitutes a distinct grade of Martensitic stainless steel. This particular grade’s enhancement in hardness and wear resistance is attributed to the meticulous integration of molybdenum (Mo) and vanadium (V) into its 7Cr17 predecessor. The international analogues of this grade include the American AISI 440A and the Japanese SUS 440A. The primary applications for this grade are in crafting high-hardness, superior wear-resistant medium to high-grade cutlery and surgical instruments.
Indeed, the ubiquitous presence of this steel grade is evident in its extensive deployment in crafting knives and scissors, including those by the globally acclaimed brand.
Compositional Insight(1)
A meticulous breakdown of 7Cr17MoV steel’s constituents is presented below:
| Element | Concentration (%) |
|---|---|
| C | 0.60-0.75 |
| Si | ≤ 1.00 |
| Mn | ≤ 1.00 |
| P | ≤ 0.04 |
| S | ≤ 0.03 |
| Cr | 16.00-18.50 |
| Mo | ≤ 0.75 |
| Ni | ≤ 0.60 |
| V | 0.10-0.20 |
Delineation of Mechanical and Physical Properties: 7Cr17MoV vs. 7Cr17
While both steels possess strikingly analogous chemical attributes, an intricate examination of their mechanical and physical properties becomes pertinent.
Mechanical Attributes(1):
- For steel plates and strips post annealing:
- Elongation: ≥ 15%
- Extension strength: ≥ 245 MPa
- HBW: ≤ 255
- HV Hardness: ≤ 269
- Material HRC Hardness: ≤ 25
- Tensile strength: ≥ 590 MPa
- For stainless steel bars:
- Material HBW Hardness: ≤ 255 (Upon Annealing)
- Material HRC Hardness: ≥ 54 (Post Quenching & Tempering) Product Link:S2038f
Physical Characteristics:(1)
Physical parameters primarily elucidate intrinsic qualities of materials sans altering their composition. In the context of 7Cr17MoV and 7Cr17, the following properties are noteworthy:
- Linear Thermal Expansion Coefficients (10-6/K): 10.2 (0-100℃), 11.7 (0-500℃)
- Density: 7.78 g/cm3
- Electrical Resistivity: 0.6 μΩ·m at 20℃
- Longitudinal Modulus for Elasticity: 200 kN/mm2 at 20℃
- Melting Point: 1371-1508℃
- Specific Heat Capacity: 160 J/Kg·K (0-100℃)
- Thermal Conductivity: 21.2 W/m·K at 100℃
Thermal Processing
To achieve the zenith of hardness, 7Cr17MoV stainless steel should be subjected to quenching at a temperature of 1070°C, whereupon it can attain a Rockwell hardness exceeding 60.0 HRC.(2） A tempering regime between 160-180℃ is advocated. Given its pronounced alloy constituents, 7Cr17MoV demands a prolonged heating sequence, specifically 4.0min/mm. It also displays superior tempering stability in comparison to 3Cr13, and is congruent with the properties of 5Cr15MoV steel.
Corrosive Resistance and Other Pertinent Properties
Both 7Cr17MoV and 7Cr17 exhibit commendable resistance to corrosion, a tribute to their significant Chromium content. Their edge retention is respectable, especially considering their predominant usage in economically-priced cutlery. While these steels are relatively softer, they facilitate effortless sharpening. Their remarkable corrosive resistance combined with decent hardness culminates in a slightly compromised toughness. Despite being categorized as budget-friendly steels, their wear resistance is laudable, courtesy of their Carbon content surpassing 0.5%.
Comparative Grading and Additional Applications
The 7Cr17MoV steel bears a striking resemblance to international grades like AISI 440A and Japanese SUS 440A.
Moreover, other applications for 7Cr17MoV and 7Cr17 encompass:
- Army knife
- Kitchen knife
- Pocket knife
- Survival knife
7Cr17MoV Products: SQT MQ21 S2029 S2045 S2043
And more from our catalogue
Reference:
- Website the world material
- SQT Lab
