CTS BD1N vs S30V Steel

CTS BD1N is manufactured by Carpenter Technology  as an advancement over their CTS BD1 steel.

CPM S30V is produced by Crucible Industries using their proprietary Crucible Particle Metallurgy (CPM) process. 

A key difference between these two steels lies in the addition of nitrogen to CTS BD1N, which enhances its corrosion resistance compared to Crucible S30V. 

CTS BD1N’s nitrogen content of 0.10-0.15% improves its corrosion resistance making it better suited for knives exposed to corrosive environments.

In contrast, S30V, while offering exceptional wear resistance and edge retention due to its 4% vanadium content and fine carbide structure, has corrosion resistance comparable to 440C stainless steel. 

CTS BD1N vs S30V Steel At A Glance

Hardness

CTS BD1N steel can achieve a hardness of up to HRC 63, while S30V steel can reach a hardness of approximately 64 HRC.

The data sheet for CTS BD1N states that it can achieve a tempered hardness capability of HRC 60-63.

On the other hand, the hardness data for S30V indicates that the maximum hardness achieved is around HRC 64.

CPM S30V ability to reach up to HRC 64 gives it a slight advantage over CTS BD1N in terms of the highest attainable hardness.

For knife applications, higher hardness generally translates to better edge retention and wear resistance.

Edge Retention

S30V steel exhibits better edge retention and wear resistance compared to CTS BD1N steel, making it a more suitable choice for knives where excellent edge retention is a priority.

The CATRA (Cutlery & Allied Trades Research Association) test results shown indicate that S30V has 145% better edge retention relative to 440C stainless steel. 

Typically S30V steel exhibits about 40% better edge retention than BD1N in CATRA edge retention Tests. The excellent edge retention of S30V is attributed to its hard vanadium carbides.

S30V contains 4% vanadium, which promotes the formation of hard vanadium carbides.

Vanadium carbides are more effective at providing wear resistance than the chromium carbides found in most steels. 

Additionally, S30V is produced via the Crucible Particle Metallurgy (CPM) process, which results in a finer and more homogeneous carbide distribution compared to conventional steels like BD1N.

Toughness

S30V steel exhibits slightly better toughness compared to CTS BD1N steel. 

S30V is produced via the CPM process, which results in a finer and more homogeneous carbide distribution. This finer carbide structure contributes to improved toughness.

Higher toughness translates to better resistance to chipping and breaking, especially in situations where the knife blade may encounter side loading or impact forces.

For larger knives, where the risk of chipping and breaking is higher due to the increased thickness and size of the blade, the superior transverse toughness of S30V makes it a more suitable choice over CTS BD1N.

Corrosion Resistance 

CTS BD1N and S30V are stainless steels, however, CTS BD1N steel exhibits better corrosion resistance compared to S30V steel.

The data sheet for CTS BD1N states that it has corrosion resistance similar to Type 410 stainless steel.

BD1N can resist corrosion from various environments like mild atmospheres, organic materials, and mild acids.

The improved corrosion resistance of CTS BD1N is attributed to its nitrogen addition of 0.10-0.15%. 

Nitrogen has a lower tendency than carbon to form chromium nitrides, leaving more chromium in solid solution to provide better corrosion resistance.

Nitrogen is less prone to form chromium nitrides, resulting in improved corrosion resistance with the nitrogen addition in BD1N.

For knives where corrosion resistance is a critical factor, such as in marine environments or exposure to acidic conditions, CTS BD1N steel would be a better choice over S30V steel.

Ease of sharpening 

CTS BD1N steel has better ease of sharpening and grindability compared to CPM S30V steel.

S30V contains 4% vanadium, which promotes the formation of hard vanadium carbides that contribute significantly to its excellent wear resistance and edge retention.

However, these hard vanadium carbides can also make the steel more difficult to grind and sharpen.

CTS BD1N does not contain any vanadium, and its carbide volume content is lower overall compared to S30V.

This lower volume of carbides, particularly the absence of hard vanadium carbides, makes CTS BD1N inherently easier to grind and sharpen.

S30V data sheet notes that while it is much easier to machine than CPM S90V and is comparable to that of D2, note that D2 steel is still harder to sharpen than CTS BD1N steel.

Final Thoughts on CTS BD1N vs S30V Steel

I would generally recommend S30V as the better overall performer for most knife applications.

While CTS BD1N offers superior corrosion resistance due to its nitrogen addition and may potentially have better grindability, these advantages are relatively minor in real-world use cases.

The improved corrosion resistance of CTS BD1N is only truly noticeable in heavily corrosive environments, which are typically not encountered in everyday knife usage. 

CPM S30V Steel exceptional wear resistance, edge retention, and toughness make it a standout choice for knives that demand high performance. 

Its 4% vanadium content and fine carbide structure from the CPM process give it a clear edge in maintaining a keen cutting edge for extended periods and resisting chipping or breakage, even in larger blade sizes.

My thoughts is that most  knife manufacturers have mastered the heat treatment process for S30V, ensuring that it consistently performs at or above its expected levels.

This proven track record and widespread adoption across the industry further solidify S30V blade steel position as a reliable and high-performing steel for knives.