Fasteners—usually the less glamorous part of a mechanical design—have been grabbing headlines lately. First it was a lack of fasteners that created (or was at least blamed for) the first delay announcement for the Boeing Dreamliner. Now two metallurgists have put out a book that really dredges up the past. In “What Really Sank the Titanic” , coauthors Jennifer Hooper McCarty and Tim Foecke say that substandard rivets were responsible for the rapid descent of the supposedly unsinkable vessel. Metallurgical testing of 48 rivets recovered from the Titanic showed that slag concentrations were at 9 percent, six or seven percent higher than they should have been. Slag is a brittle byproduct of the iron making process. Design engineers put the weaker rivets in areas expected to see less stress, such as the bow. Unfortunately, that is right where the Titanic scraped an iceberg. McCarty and Foecke postulate that fewer compartments would have burst if better rivets had been used. It’s possible, they say, that the Titanic could even have limped into Halifax. They also suggest that the bad rivets may have resulted from a rush to get the boat built at a time when rivets were in tight supply.
A new compression molding compound material combines the light weight, strength, and rigidity of carbon fibers with the flexibility and lower cost of glass materials in a composite compatible with automotive production.
Plastic bearings are real and millions of them are in use doing heavy-duty jobs we used to think only metals could do. Some of Germany-based igus's bearings are traveling around the world as functional parts in a car to demonstrate what they can do.
Baxter showed off his 2.0-derived moves at ATX West this year. The big red guy still looks pretty much the same, but has some new abilities, mostly due to software. The research robot version is now being used in corporate R&D departments as a design platform.
End-production using 3D printing, including objects made of multiple materials in one pass, is getting closer to reality as we saw on the exhibit floor at the recent Pacific Design & Manufacturing Show.