Keeping up with the Smiths

Some coworkers were talking about the shows "Elementary" (Lucy Liu and somebody -- who cares?) and "Sherlock" with what's-his-face Inglebert Humperdink who inexplicably played Khan Nunian Singh in Star Trek: Into Darkness.

Reminded me of the Robert Downey Jr. movie (he's one of my favs -- have you seen Less Than Zero? -- another good "drug addict movie"), Sherlock Holmes (the first one).  In demonstrating (under protest) his powers of deduction to Watson's fiancee, he pulls out Watson's walking stick / sword and says it's made of "tensile steel".  That rankled.

It's problematic on several levels, and the research director let the side down.

The correct term is "high-tensile steel" (or for the uber-anal-retentive materials scientists out there, probably and technically "high-tensile-strength steel"), which means, as the name suggests, that the steel is good under tension, probably suitable for cables.  Probably not so important for girders, rails, and probably not swords.  It sounds good, though, unless you're a metalurgist or went to school in Pittsburgh, or have any engineering or construction knowledge whatever.

In Japanese swords, Bethlehem steel swords and knives, and pretty much anywhere, the metalurgical properties most prized are, I think, elasticity and hardness, which are, unfortunately, mutually exclusive, and therefore the ability to force a sword which has a) a blade edge which is hard, mainly to the end that it can be sharpened very keenly and keep that edge, and b) a blade body (these are both non-technical terms) that will not be brittle and break under impact, which would happen if the whole sword were hard like the blade, and by the same token, the edge would not cut well and would not hold a sharpening if it were elastic like the blade.  Elasticity derives from the carbon (and other?) alloying of the steel, and the forging technique, and the same goes for the blade, and also quenching techniques are used to make the blade.  It comes down to the crystalline structure of the finished steel, and the blade and the edge need to have different ones, which is tricky and usually the result of a highly-prized and often top-secret process.

Ductility is a property that goes to some degree with tensile strength (the ability to stretch and extrude a metal into wires, or pound it into sheets or other shapes) so might be good to a degree in the process of forging swords.

In short,

a) "tensile steel" is a nonsense term, rather like "height person"

b) high-tensile (strength) steel is probably completely wrong for swordsmithing (even if RD Jr simply flubbed his lines or whatever)

c) this may represent a gratuitous peppering of impressive-sounding terms, i.e., "tajingo" (the language of the other), and obviously it fell flat with me

d) This is the kind of thing I try to avoid, i.e., "over-committing" to irrelevant details, especially those outside (or even within) my area of expertise

d.1.) I probably fail in this more than I am aware, but it's a principle I try to think about.

I may be totally full of crap on part or all of this, so please correct if you find so