Which begs the question . . . are the lawn mower blades actually heat treated at all?
That is a good question, one for which I don't have an answer. Well, actually I do have an answer but it doesn't help to say "I dunno".
I'm not too concerned about pieces breaking off 'cause the blades shouldn't end up being brittle, just hard.
Brittle: A material is brittle if, when subjected to stress, it breaks without significant deformation (strain). Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Breaking is often accompanied by a snapping sound. Brittle materials include most ceramics and glasses (which do not deform plastically) and some polymers, such as PMMA and polystyrene. Many steels become brittle at low temperatures (see ductile-brittle transition temperature), depending on their composition and processing.Hardness: Hardness is a measure of how resistant solid matter is to various kinds of permanent shape change when a force is applied. Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, there are different measurements of hardness: scratch hardness, indentation hardness, and rebound hardness.I'm hoping the blades will have a fair amount of "indention hardness".
