Scenario: a spec sheet says “very hard” and a buyer reads it as “very strong”. Direct answer: not necessarily. Hardness describes resistance to local indentation or scratching. Toughness describes how much energy a material can absorb before it fractures. A plow edge needs a useful balance of both, and the right balance depends on the duty.
Myth 1: “The hardest edge lasts longest”
Reality: harder materials often resist abrasive wear better, which can lengthen life on smooth pavement. But on routes with manholes, joints and curbs, a very hard material may chip, and chipped edges can fail early. What to do: match material to the route’s hazard level, not to the highest hardness figure on a sheet.
Myth 2: “Soft steel is weak steel”
Reality: a softer, tougher steel may bend rather than crack when it hits something. Bending is damage, but it is often easier to see and survive than a sudden fracture. What to do: think in failure modes: wearing away, bending, chipping, cracking.
Myth 3: “One number describes the edge”
Reality: a single hardness reading does not capture toughness, heat treatment history or how a carbide insert is joined to its carrier. What to do: ask for the full specification and a description of what was tested, as covered in our hardness-spec article.
Myth 4: “If it chipped, the supplier made it badly”
Reality: chipping can come from poor material, but also from a hard impact the edge was never meant to take. What to do: look at where the chip is, what the route holds and whether the pattern repeats across trucks.
A quick way to reason about it
| Failure seen | Leans toward | Question to ask |
|---|---|---|
| Smooth, even loss of height | Abrasion | Would more wear resistance help? |
| Bent edge | Impact above the steel’s capacity | Is there a hazard to mark or avoid? |
| Chips at insert edges | Brittle impact failure | Is the duty too rough for this design? |
| Cracks at bolt holes | Stress concentration | Are bolts, holes and torque correct? |
No specific hardness values are given because they depend on material and standard, and I have not tested any product.
Boundary: this is a general explanation, not a material specification. Values for a given edge must come from its supplier and its test standard.
Further reading on this site.
Steel Grades for Plow Edges: Hardness, Toughness and Weldability Trade-Offs ↗Tungsten Carbide Inserts for Snow Plow Edges: Grade, Size and Spacing Explained ↗Tungsten carbide inserts for snow plow edges ↗What Salt-Spray Hours Mean for Plow Hardware: ASTM B117 in Plain English ↗
