Saturday, June 08, 2019

Headline complaints

The headline reads "Metal Foam Stops .50 Caliber Rounds as Well as Steel – At Less Than Half the Weight". If you read the article, "stops" isn't quite the right word to use. The composite armor "was able to absorb 72-75% of the kinetic energy of the ball rounds." That's more than ok for something light, but the headline is misleading. I presume that the impact turns into many collapses and spallations inside the "bubbles" and helps dissipate the energy--a bit like crunchable bumpers, but at higher energy.

In addition, "CMFs, in addition to being lightweight, are very effective at shielding X-rays, gamma rays and neutron radiation" is misleading, and so is the article it links to. Steel is better than aluminum, and not so good as lead is the right answer--and one of the commenters pointed that out, noting that the researcher's real abstract didn't claim otherwise. Radiation gets stopped by stuff, not structure.

2 comments:

Assistant Village Idiot said...

Journalists are drawn almost entirely from one of CP Snow's Two Cultures, and do not understand the other very well. Even worse, they are increasingly drawn from the third culture, social science, which he added later.

james said...

To make matters worse, some researchers go along with it. It sometimes seems as though one has to hype results in order to get attention, not to mention funding.