Intended Use
This is probably the #1 factor in choosing a survival knife is choosing the right type of steel for your blade type. Its critical to use the right knife for the job required. No survival knife is going to be used for any one task but if there is a set of tasks you intend the survival knife to perform then this information is helpful when determining the type of survival knife you want.
What is your preferred cutting style. Push Cutting or Slicing? You may use a combination of both depending on the sharpness and performance of the knife. High edge stability is needed for push cutting. If you prefer slicing a coarse edge will do better.
While all steels can perform with coarse edges, very fine edges with low angles don’t work well on high alloy, high carbide volume alloys. You would need fine-grained, low carbide volume alloys to achieve best results.
Finally, before we dive into other performance factors, it’s important to note that putting a proper edge on any knife will provide most of its performance, regardless of the alloy.
Sooner or later, all knives must be sharpened. A dull knife with high-end steel performs worse than a sharp budget knife. So regardless of how much money you spend on your knife be sure to keep it sharp. Better steel allows either for a thinner or more durable edge, or both, but it needs to sharpened and maintained.
Performance
How long a survival knife can keep its edge should be a factor in choosing a survival knife as it affects your cutting the ability and speed of use. A knife that stays sharp longer performs better and requires less maintenance. A knife that keeps its edge longer cuts faster and with less issues. Sharpening a knife is easier than it use to be but its still time and effort towards something that isn’t getting the main task at hand complete.
Blade Geometry
Blade geometry is the next factor in choosing a survival knife. An important aspect of blade geometry is blade thickness. Thicker knives are stronger but sacrifice cutting ability, as thin knives always cut better than thicker knives but are weaker. One thing you can do when buying thinner knives is get select a stronger steel for the blade such as as CPM 3V or A2. However, a 3/8″-1/4″ thickness provides plenty of strength for most knives.
Edge Geometry
Edge geometry is defined by the shape and angle at which the edge is sharpened. As far as angles go, thin edges cut better while thick edges are stronger and more durable. The interesting this is because thicker edges require more force when cutting, they don’t last longer than thinner edges proportionally. As for the possible edge configurations, there’s quite a few to choose from. When it comes to sharpness Chisel edge knives are sharpest, followed by the Flat V Grind, followed by Convex, followed by Hollow Grind. Keep these edge types in consideration when choosing a survival knife.
Sharpness
- Chisel
- Flat V Grind
- Convex
- Hollow Grind
With V edge knives you’ll need a sharpening system to make a proper edge because its not possible for the human hand to make a straight angle. If you want a V grind, pick fine-grained alloy. Also note that not all alloys can support edges below 15° per side, or 30° inclusive. Other than that, intended use should define what type of edge you want on your knife.
Corrosion Resistance
Stain-resistant alloys are more prevalent in folding knives because they require less maintenance and can take more abuse from environment and neglect.
Many people think that stainless steel knives are more brittle, harder to sharpen and more susceptible to breaking. The reality is stainless steels knives are more neglected and any neglected knife will become more brittle, harder to sharpen, and break more often.
How brittle a knife is depends on heat treatment, geometry, blade thickness and other design aspects. Yes, stain-resistant alloys are not as tough as some of the carbon or tool steels, but that doesn’t mean they are brittle on their own. What is more important is the fact that the fine edge is the most susceptible to corrosion than the rest of the blade.
If you do research, you can find quite a few puzzled reports of razor-sharp carbon steel knives getting dull just by sitting in the drawer. That can be avoided if you keep them oiled in the drawer; nevertheless, if you expect humid or aggressive environments for your knife, stain-resistant steel can be a better option.
Carbon & Tool Steels
If corrosion resistance is not a concern, then there are a lot of very good alloys to choose from. There is no official rule separating carbon steels from tool steels
Overall, tool steels is a very large category with many subgroups. None of those alloys were designed to be used in knives, but some of them happen to work very well. More specifically, high speed and cold working tool steels have quite a few good choices. Even though a lot of tool steels work well for knives, just because a steel is in a tool steel category doesn’t automatically make it a good choice for survival knives. Humans cut very differently compared to machines, industrial tools maybe meant to cut things but they don’t cut things like a human would in the wild.
