CPM S35VN vs CPM S45VN Knife Steel Comparison

CPM-S35VN vs. CPM-S45VN – A Comprehensive Comparison for Knife Enthusiasts

Knife enthusiasts are constantly on the lookout for the latest and greatest steels, seeking the ideal balance of edge retention, toughness, corrosion resistance, and ease of sharpening. Two popular stainless “super steels” that often come up in this discussion are CPM-S35VN and CPM-S45VN. Both are produced via Crucible Particle Metallurgy (CPM), which refines the steel’s grain structure for improved performance. Yet, there are important distinctions between them—such as chemical composition, heat-treatment nuances, and real-world practicality—that can help you decide which is best for your needs.

In this comprehensive blog post, we’ll explore both steels individually, compare them side by side, and provide guidance on choosing the right one for your environment and cutting tasks.

---

1. OVERVIEW OF CPM-S35VN

1.1 Chemical Composition and Alloy Elements

CPM-S35VN is a powdered metallurgy steel developed as an evolution of the benchmark CPM-S30V. Its nominal composition includes:

• Carbon (C): ~1.38%
• Chromium (Cr): ~14%
• Molybdenum (Mo): ~2%
• Vanadium (V): ~3%
• Niobium (Nb): ~0.5%

Key Alloying Elements and Their Effects:

• Carbon: Increases hardness and wear resistance.
• Chromium: Enhances corrosion resistance and contributes to hardness.
• Molybdenum: Improves toughness, hardenability, and overall strength.
• Vanadium: Refines grain size, improves wear resistance, and helps maintain a fine edge.
• Niobium: Helps refine carbides, improving toughness and edge stability.

1.2 Typical Hardness (Rockwell C) Ranges & Practical Implications

You’ll typically find CPM-S35VN knife steel hardened around 58–61 HRC. At the lower end (58 HRC), you get slightly improved toughness at the expense of some edge retention. At higher hardness (60–61 HRC), you gain additional wear resistance. This range provides a balanced profile, making CPM-S35VN suitable for numerous cutting tasks—from everyday carry (EDC) folders to mid-sized fixed blades.

1.3 Heat-Treatment Nuances and Forging

CPM-S35VN, while more forgiving than some other “super steels,” still benefits from precise heat treatment. Because it’s a stainless steel with higher chromium content, controlling heating and cooling cycles is essential to prevent issues like carbide segregation. Proper quenching and tempering yield optimal hardness, toughness, and corrosion resistance. Warping or cracking can occur if not carefully handled, but experienced heat-treaters (including respected brands like Spyderco, Benchmade, and Chris Reeve Knives) have well-established protocols.

Tip: For most knives, a sharpening angle between 15–20 degrees per side is common for S35VN. Its fine grain structure responds well to both standard and diamond sharpening stones.

1.4 Key Performance Characteristics

• Corrosion Resistance: Very good
• Toughness: Good
• Edge Retention: Good
• Ease of Sharpening: Good

1.5 Patina Formation and Protective Coatings

Unlike high-carbon steels (e.g., 1095, O1) that naturally develop patinas, CPM-S35VN is stainless enough that any patina would be minimal to non-existent in normal use. Protective coatings are not necessary for corrosion prevention; they’re more of an aesthetic or friction-reducing choice.

1.6 Ideal Uses and Why Pick CPM-S35VN

Thanks to its balanced properties, CPM-S35VN is a tremendous all-rounder steel. It offers enough toughness for moderate bushcraft tasks, plenty of edge retention for EDC use, and very good corrosion resistance for humid or marine environments. Enthusiasts often pick S35VN because it hits the sweet spot—delivering user-friendly sharpening, excellent all-around performance, and a proven track record.

---

2. OVERVIEW OF CPM-S45VN

2.1 Chemical Composition and Alloy Elements

CPM-S45VN represents another step in the evolution of Crucible’s stainless steel lineup, introduced around 2019–2020. Its nominal composition includes:

• Carbon (C): ~1.48%
• Chromium (Cr): ~16%
• Molybdenum (Mo): ~2%
• Vanadium (V): ~3%
• Niobium (Nb): ~0.5%
• Nitrogen (N): ~0.15%

Key Alloying Elements and Their Effects:

• Increased Chromium (16%): Significantly boosts corrosion resistance.
• Slightly Higher Carbon (~1.48%): Potentially increases wear resistance and hardness.
• Nitrogen: Contributes further to corrosion resistance and can help refine the grain structure.

2.2 Typical Hardness (Rockwell C) Ranges & Practical Implications

CPM-S45VN knife steel is commonly hardened between 60–62 HRC. This slightly higher hardness potential—coupled with a refined microstructure—can translate into a small but noticeable boost in edge stability and wear resistance. Many knifemakers aim for around 60–61 HRC to balance edge retention with daily use toughness.

2.3 Heat-Treatment Nuances and Forging

Like CPM-S35VN, CPM-S45VN requires precise temperature control throughout its heat-treatment to achieve consistent results. The additional chromium and nitrogen confer high stain resistance, but forging must be carefully managed to avoid chromium carbide precipitation at incorrect temperatures. Brands adopting S45VN have quickly established best practices to minimize warping or cracking.

Note on Finishing and Polish: Some users find that S45VN can take a high level of polish thanks to its fine microstructure—an appealing feature if you prefer a mirror-finished blade.

2.4 Key Performance Characteristics

• Corrosion Resistance: Excellent
• Toughness: Good
• Edge Retention: Good
• Ease of Sharpening: Good

2.5 Patina Formation and Protective Coatings

Similar to S35VN, CPM-S45VN is a stainless steel that typically will not form a patina under normal conditions. Its combination of chromium and nitrogen significantly resists rust, so coatings become more of a preference choice (e.g., for tactical aesthetics or branding) rather than a necessity.

2.6 Ideal Uses and Why Pick CPM-S45VN

Knife enthusiasts who like the performance envelope of S35VN but want a little extra corrosion resistance or slightly higher hardness potential may gravitate toward S45VN. It shines in environments where moisture, salt, or humidity are major concerns—such as maritime or tropical regions. It’s also an excellent choice for EDC or folding knives that demand top-tier stain resistance and a refined edge that still offers respectable toughness.

---

3. SIDE-BY-SIDE COMPARISON TABLE

Property	CPM-S35VN	CPM-S45VN
Carbon Content	~1.38%	~1.48%
Chromium Content	~14%	~16%
Typical Hardness	58–61 HRC	60–62 HRC
Corrosion Resistance	Very Good	Excellent
Toughness	Good	Good
Edge Retention	Good	Good
Ease of Sharpening	Good	Good
Patina Formation	Rarely forms patina	Rarely forms patina

---

4. REAL-WORLD APPLICATIONS

4.1 Bushcraft and Outdoor Tasks

Both steels can handle moderate chopping, feather-sticking, and other bushcraft tasks, though neither is as tough as some lower-alloy tool steels (e.g., CPM-3V) designed expressly for heavy impacts. CPM-S35VN’s slightly lower hardness range can give it a small advantage in resisting chipping during serious impact tasks. However, S45VN’s toughness is still “good” and adequate for most outdoor settings.

4.2 EDC (Everyday Carry) Folders

Both steels excel in folding knives, offering good wear resistance, solid toughness, and strong corrosion resistance. S45VN’s subtle edge in corrosion resistance might be desirable if your daily routine involves exposure to sweat, saltwater, or harsh chemicals.

4.3 Kitchen Use

In a kitchen environment, both steels are more than corrosion-resistant enough. S35VN’s ease of sharpening and S45VN’s excellent stain resistance serve equally well. If you often forget to dry your blade after washing, S45VN provides extra peace of mind against rust spots or pitting.

4.4 Survival or Tactical Applications

Both can serve in survival or tactical roles. S35VN, known for its balanced properties, might be marginally less prone to micro-chipping at slightly lower hardness. S45VN’s higher potential hardness can help hold a razor edge a bit longer if you keep the blade consistently maintained.

---

5. COST, AVAILABILITY, AND MAINTENANCE

5.1 Cost

CPM-S35VN is already considered a premium steel, and CPM-S45VN is typically priced similarly or slightly higher, depending on the knifemaker. Since S45VN is relatively newer, expect a small premium—though prices may normalize as more manufacturers adopt it.

5.2 Availability

CPM-S35VN has been widespread for years and is used by many production and custom knife makers alike. S45VN is steadily gaining traction; you’ll find it increasingly offered in mid- to high-end production knives and custom builds. Over time, it is likely to become more common.

5.3 Maintenance

• Clean the blade after use, especially if you’ve encountered acidic substances or saltwater.
• Light oiling or waxing is optional but can enhance longevity.
• Sharpening can be done with standard stones, diamond plates, or ceramic rods. Neither steel is extremely difficult to sharpen, though S45VN’s higher hardness means you’ll benefit from good technique and consistent angle control.

Resource: For more detailed heat-treatment and metallurgical data, check out the official Crucible Data Sheets for CPM-S35VN and CPM-S45VN.

---

6. PROS AND CONS

CPM-S35VN

Pros:

• Well-rounded performance (good toughness, edge retention, corrosion resistance, and ease of sharpening).
• Widely available with more heat-treatment “recipes” established among manufacturers.
• Generally slightly lower cost compared to S45VN.

Cons:

• Slightly lower corrosion resistance than S45VN.
• Marginally less potential hardness if you’re chasing the highest Rockwell ratings.

CPM-S45VN

Pros:

• Excellent corrosion resistance—great for humid or marine environments.
• Good overall balance of hardness, wear resistance, and toughness.
• Increasingly popular among premium knife makers for high-end EDCs.

Cons:

• Often priced a bit higher due to its recent introduction and prestige.
• Heat-treatment specifics still being refined across different manufacturers (less historical data than S35VN).

---

7. RECOMMENDATIONS & KEY TAKEAWAYS

• Best for Durability: Both S35VN and S45VN have good toughness. For heavy-impact tasks, S35VN’s slightly lower hardness range may reduce the risk of chipping.
• Best for Corrosion Resistance: S45VN wins here, thanks to its higher chromium content and added nitrogen.
• Balanced Everyday Use: S35VN remains an excellent, proven option with good availability and cost-effectiveness. S45VN offers incremental improvements for those who want the best possible stain resistance.
• Heat-Treatment Factors: Whichever steel you choose, real-world performance depends heavily on proper heat-treatment. Reputable brands like Chris Reeve Knives, Spyderco, and Benchmade have refined processes for consistent results.
• Patina & Coatings: Neither steel is prone to forming a patina under normal conditions, and protective coatings are more aesthetic than functional in this case.

---

CONCLUSION

Both CPM-S35VN and CPM-S45VN are excellent examples of modern stainless “super steels,” offering a balanced profile of good toughness, good edge retention, and high corrosion resistance. S35VN’s longstanding reputation, broad availability, and proven history make it a go-to for many knife enthusiasts, while S45VN offers incremental improvements in corrosion resistance and hardness potential—making it alluring for those seeking a top-tier stainless performance with a slight premium.

When deciding between these two steels, consider your environment, intended use, and sharpening habits. If your primary concern is having the most rust-resistant blade in a humid or salty region, S45VN may be worth the investment. If you want a proven, well-rounded performer that’s easier to find (and often more budget-friendly), S35VN won’t disappoint. In either case, you’re unlikely to regret choosing one of these well-respected CPM steels for your next knife—especially if it’s from a reputable maker with a refined heat-treatment protocol.

---

Optional FAQ Section for SEO

Q: Which steel is better for a maritime environment—CPM-S35VN or CPM-S45VN?
A: CPM-S45VN offers superior corrosion resistance due to its higher chromium content and added nitrogen. If you’re around saltwater regularly, it’s a great pick.

Q: Is CPM-S45VN worth the upgrade over S35VN for EDC?
A: If you value top-tier stain resistance and a slightly higher hardness potential, go for S45VN. Otherwise, S35VN remains an exceptional all-rounder that’s more readily available.

Q: How do I sharpen S35VN and S45VN efficiently?
A: Both respond well to diamond stones, ceramic rods, or standard whetstones. Aim for a 15–20 degree angle per side. S45VN may require a bit more care if hardened above 61 HRC.

---

With these tweaks, the post offers additional clarity, real-world context, and relevant SEO keywords—helping it reach a broader audience of knife enthusiasts.