AEB-L vs MagnaCut Steel

MagnaCut is a new knife steel developed by Dr Larrin and Crucible Industries, while AEB-L is a stainless steel produced by Uddeholm.

AEB-L steel was originally produced as a razor and scalpel steel but found its way into knives due to its excellent balance of toughness, edge retention and corrosion resistance.

MagnaCut offers significantly higher hardness potential and improved edge-holding capability compared to AEB-L steel. 

However, AEB-L holds an advantage in overall toughness due to its finer and lower volume fraction of brittle carbides.

While MagnaCut exhibits excellent toughness for a high-alloy powder metallurgy stainless steel, matching or exceeding steels like CPM-4V, AEB-L toughness at higher hardness levels remains unmatched.

AEB-L vs MagnaCut Steel At A Glance

Hardness

CPM MagnaCut steel exhibits significantly higher hardness potential than AEB-L steel. 

While AEB-L can achieve hardness levels up to around 63-64 Rc with cryogenic treatment, MagnaCut can reach even higher hardness, with reported values up to 65.5 Rc by some knifemakers.

The hardness testing data shows that MagnaCut can attain hardness levels over 63 Rc without cold treatment.

MagnaCut attains over 65 Rc with cryo or freezer treatment, surpassing the maximum hardness levels achievable by AEB-L. 

Furthermore, MagnaCut maintains its high hardness level even when heat-treated in industrial vacuum furnaces used by larger knife companies.

This superior hardness capability of MagnaCut steel allows for improved wear resistance and edge stability for knives.

This makes MagnaCut knife steel more suitable for applications requiring exceptional edge retention and wear resistance.

Toughness

 AEB-L steel exhibits better toughness compared to MagnaCut steel, due to its finer and lower volume fraction of brittle carbides.

Toughness testing by Crucible shows MagnaCut matches or exceeds the toughness of other high-toughness steels like CPM-M4, A2, and CPM-4V, with values around 30 – 38 ft-lbs at hardness levels of 62.5-64 Rc. 

However,  independent testing show AEB-L achieves even higher toughness values, reaching around 40 -45 ft-lbs at a similar hardness of 62.2 Rc.

AEB-L stainless steel behaves much like low alloy carbon steels like 52100 steel and O1 steel in toughness ratings.

Therefore, while MagnaCut exhibits excellent toughness for a high-alloy PM stainless steel, AEB-L to has an advantage in overall toughness, particularly at higher hardness levels.

Edge Retention

MagnaCut steel exhibits better edge retention and wear resistance compared to AEB-L steel due to the presence of hard vanadium carbides. 

The CATRA slicing-edge retention testing performed on MagnaCut knife steel at different hardness levels showed it matched the edge retention of steels like S35VN, and 3V while exceeding AEB-L steel.

 AEB-L is noted for its excellent edge geometry performance due to its high toughness, allowing acute edge angles excellent for tough cuts like push cuts.

However, the wear resistance and CATRAslicing edge retention measures indicate that MagnaCut is the superior steel for maintaining a sharp edge over time.

It is worth noting that the edge grind type and heat treatment matter significantly in the difference in edge retention on these two blade steels.

Custom knife makers like WC knives AEB-L blades have proven to be really good on edge retention performance. 

In one of his YouTube edge retention videos, he shows AEB-L going head-to-head with MagnaCut, closely matching its rope-cutting performance.

Corrosion Resistance

MagnaCut and AEB-L are stainless steels with excellent corrosion resistance, however, MagnaCut steel exhibits significantly better corrosion resistance than AEB-L steel. 

In 1% saltwater immersion testing for 72 hours, MagnaCut showed no visible signs of corrosion or spotting. 

Further testing in 3.5% salt water for 72 hours revealed that MagnaCut corrosion resistance is just shy of Vanax or LC200N, but it substantially outperforms AEB-L and other steels like S45VN and M390. 

MagnaCut stainless steel exceptional corrosion resistance is attributed to eliminating chromium carbides in its microstructure, which prevents locally chromium-depleted regions susceptible to corrosion. 

In contrast, AEB-L, being a conventional stainless steel, contains chromium carbides that can lead to such localized areas prone to corrosion.

In daily tasks that do not involve exposure of this blade steel to corrosive environments, you might not notice the superior corrosion resistance of MagnaCut steel.

Ease of Sharpening

MagnaCut steel exhibits slightly better grindability and ease of sharpening compared to AEB-L steel. 

Despite having a higher volume fraction of hard vanadium and niobium carbides, MagnaCut’s finer overall carbide structure allows for easier grinding and finishing than expected.

Crucible reports that MagnaCut grinds and finishes more easily than steels like S30V and S45VN, which have a lower overall carbide content.

In direct comparisons, MagnaCut was significantly easier to grind than CPM-4V despite having similar carbide volumes. 

Sharpening MagnaCut is also relatively easy, with good feedback on stones and responsive burr removal during stropping.

Some knifemakers noted that MagnaCut sharpened better than steels like CPM-154 and took a superior edge.

In contrast, while AEB-L excels in grindability and ease of sharpening compared to most other stainless steels due to its low wear resistance, it still lags behind MagnaCut. 

Final Thoughts on  AEB-L vs MagnaCut Steel

In conclusion, having used both MagnaCut and AEB-L knives extensively, I can attest to the distinct advantages each steel offers.

MagnaCut and AEB-L excel in their respective strengths, with MagnaCut offering a higher attainable hardness and enhanced edge retention. 

In contrast, AEB-L boasts an exceptional balance of toughness, corrosion resistance, and the ability to create ultra-thin, high-performance edges.

AEB-L has always truly impressed me with its remarkable toughness and corrosion resistance, allowing for blades with outstanding edge stability. 

The ability to achieve remarkably thin edges without chipping or rolling is a testament to AEB-L steel impressive toughness. 

Over the past year, however, my experience with MagnaCut has revealed its superior edge retention capabilities, proving better suited for daily usage where maintaining a keen edge is crucial. 

While lab testing has undoubtedly demonstrated MagnaCut’s extensively impressive corrosion resistance, I have found its edge-holding properties to be the standout feature in my personal use.