SLD-Magic Steel Test: Hardness & Microstructure | OLITANS
Knife-steel specifications are useful, but a cross-section can reveal details that a product page cannot. In an independent destructive evaluation, Taylor Hardness sectioned an OLITANS Gecko blade made with laminated SLD-Magic steel, measured the hardness of its individual layers, and examined the etched microstructure under magnification. The cutting core averaged 701.00 HV0.5, approximately 60 HRC.
What Was Tested?
The test used one OLITANS Gecko blade with a laminated construction: a harder SLD-Magic cutting core surrounded by softer outer layers. This matters because a conventional hardness reading taken only on the blade exterior does not directly measure the steel at the cutting core.
The reviewer initially took a Rockwell C reading on the laminated exterior using a Mitutoyo HR-530. It produced a value of 47.2 HRC, but the reviewer explicitly identified that reading as not a valid result. It should not be reported as the hardness of the SLD-Magic cutting steel.
How the SLD-Magic Blade Was Examined
The blade was cross-sectioned, mounted, and polished in accordance with ASTM E3 specimen-preparation guidance. Microhardness testing was then performed in accordance with ASTM E384 using a Clark CLC-10 and a Vickers 500 gf load, reported as HV0.5. Five readings were taken in the core and five in the outer jacket before an average was calculated for each layer.
For microscopic examination, the sample was etched according to ASTM E407 using Marble's etchant. These preparation and testing methods allowed the reviewer to evaluate small, specific regions of the laminated blade rather than treating the entire cross-section as one uniform material.
Hardness Results: Core vs. Jacket
| Blade region | Five HV0.5 readings | Average | Reviewer’s approximate HRC conversion |
|---|---|---|---|
| SLD-Magic cutting core | 702.33, 702.99, 700.34, 699.03, 700.34 | 701.00 HV0.5 | ~60 HRC |
| Outer jacket | 621.24, 619.58, 627.35, 621.70, 626.79 | 623.33 HV0.5 | ~56.5 HRC |
The result that matters most for cutting is the core measurement because the core forms the working edge. In this sample, the five core readings were tightly grouped—from 699.03 to 702.99 HV0.5—and averaged approximately 60 HRC after conversion. The outer jacket averaged approximately 56.5 HRC.
This single-sample result is consistent with the approximately 60 HRC specification used for current OLITANS SLD-Magic models. It is supporting evidence for the tested blade, not a substitute for batch-level quality-control records.
What the Microstructure Showed
After etching and examination at multiple locations and magnifications, the reviewer described a carbide-rich tempered martensitic microstructure. Large, undissolved, irregularly shaped carbides were visible within the matrix.
In practical terms, hardness and carbide structure are relevant to how a knife steel resists wear and supports an edge. However, microscopy alone does not establish real-world edge retention, toughness, corrosion resistance, or ease of sharpening. Those performance characteristics require their own controlled tests.
A Closer Look at the Lamination Line
Photomicrographs also showed a distinct boundary between the core and the jacket, including a thick white interlayer that resisted the etchants used in the examination. The reviewer considered nickel or a nickel-based alloy the most likely explanation, while also noting that a high-grade stainless steel such as a 300-series alloy could behave similarly.
That composition was not chemically verified, so the interlayer should be described as an unconfirmed, etch-resistant layer rather than definitively identified as nickel.
What This Test Tells Us—and What It Does Not
- It does show that the SLD-Magic cutting core in this sample averaged 701.00 HV0.5, reported by the reviewer as approximately 60 HRC.
- It does show that the outer jacket measured lower than the cutting core in this sample.
- It does show a carbide-rich tempered martensitic structure and a visible laminated boundary.
- It does not show that 47.2 HRC is the blade-core hardness; that exterior macrohardness reading was expressly marked invalid.
- It does not identify the white interlayer by chemical analysis.
- It does not replace controlled edge-retention, toughness, corrosion, or batch-consistency testing.
Why This Matters When Choosing a Knife
For a buyer comparing knife steels, this test provides something more useful than an unsupported hardness claim: it shows where the measurements were taken, reports all five readings for each layer, and pairs the numbers with an examination of the cross-section.
The approximately 60 HRC core result makes this tested SLD-Magic blade relevant to users who value wear resistance and edge stability in an EDC folder. As with any knife steel, the complete experience also depends on edge geometry, heat treatment, intended cutting tasks, maintenance, and sharpening technique—not hardness alone.
Explore OLITANS SLD-Magic knives or compare the construction and dimensions of individual Gecko models before choosing the version that fits your carry.
SLD-Magic Steel Test FAQ
How hard was the SLD-Magic core in the tested OLITANS Gecko?
Five Vickers HV0.5 readings produced an average of 701.00 HV0.5. The independent reviewer reported this as approximately 60 HRC.
Why was the outer jacket softer than the core?
The blade uses laminated construction, so the cutting core and surrounding jacket are separate regions with different measured hardness. In the tested sample, the core averaged approximately 60 HRC and the jacket approximately 56.5 HRC.
Does the 47.2 HRC reading mean the SLD-Magic blade is only 47.2 HRC?
No. That reading was taken on the laminated exterior, and the reviewer explicitly stated that it was not a valid result. The sectioned cutting core was evaluated separately through Vickers microhardness testing.
What does HV0.5 mean?
HV identifies a Vickers hardness measurement, and 0.5 indicates a 0.5 kgf test load. This microhardness method can measure small, specific regions—such as the core and jacket of a laminated blade—that may be unsuitable for a conventional macrohardness reading.
Was the white lamination layer confirmed to be nickel?
No. The reviewer considered nickel or a nickel-based alloy the most likely explanation, but also noted another possible stainless-steel composition. Without chemical analysis, its exact composition remains unconfirmed.
Does 60 HRC prove edge retention or toughness?
No. Hardness is one useful material measurement, but real-world cutting performance also depends on microstructure, heat treatment, edge geometry, blade thickness, and the task. Dedicated testing is needed to compare edge retention, toughness, and corrosion resistance.
Source and test credit: Taylor Hardness (view the original Instagram test), published August 17, 2026. OLITANS supplied the test sample.
Methods referenced by the reviewer: ASTM E3 for metallographic specimen preparation, ASTM E384 for microindentation hardness, and ASTM E407 for microetching metals and alloys.