#materials engineering

For 200 years, scientists have failed to grow a common mineral in the laboratory under the conditions believed to have formed it naturally. Now, a team of researchers from the University of Michigan and Hokkaido University in Sapporo, Japan have finally succeeded, thanks to a new theory developed from atomic simulations. Their success resolves a long-standing geology mystery called the "Dolomite Problem." Dolomite—a key mineral in the Dolomite mountains in Italy, Niagara Falls, the White Cliffs of Dover and Utah's Hoodoos—is very abundant in rocks older than 100 million years, but nearly absent in younger formations. "If we understand how dolomite grows in nature, we might learn new strategies to promote the crystal growth of modern technological materials," said Wenhao Sun, the Dow Early Career Professor of Materials Science and Engineering at U-M and the corresponding author of the paper published today in Science. The secret to finally growing dolomite in the lab was removing defects in the mineral structure as it grows. When minerals form in water, atoms usually deposit neatly onto an edge of the growing crystal surface. However, the growth edge of dolomite consists of alternating rows of calcium and magnesium.

20/08/24

I forgot to post this yesterday 'cause I got home so late from uni 😭

Yesterday was a pretty tiring, but worth it, day of studying since I missed an entire week of class and had to study all of the content from last week's welding technology class + study from a texbook on science and engineering of materials.

Content studied yesterday:

> Stress-Strain of metals under tension, compression, sheer and torsion tests ;

> Stress-Strain graph (elastic and plastic strain, recognition of ductile and brittle materials, points of elastic limit, yielding, ultimate strength and rupture) ;

> General types of welding ;

> Concepts of welding technology .

My welding technology class went great and I was relieved when I found myself following the explanations with ease and being able to participate because of successful studying and absorption of the last class' content through photos of the board that my classmate sent me. I was really scared I would fall behind but I feel pretty confident and intrigued by the subject and engineering in general... I think I'm finally falling in love with it!

I am in absolute horrified Awe. Like. I don’t know much about submarines, but I know rockets and we use carbon fiber for hobby rockets and. You can’t?? Make a pressurized vessel out of carbon fiber?? And expect it to survive cyclical loads?? Especially one experiencing temperatures as low as the waters by the Titanic!! Like the polymer matrix would DEFFO experience embrittlement and at MINIMUM crack but more likely would fail catastrophically!! Your threasbold for acceptable cracking would be MINISCULE at that pressure; you couldn’t afford brittle cracking almost at all!!

This article goes into some detail about the safety concerns with the material used and how they were literally brought up and ignored! like. This is the literal scenario they train us for ethics wise in college! Legit the definition! Of when you should put human life before the company!!

Idk it’s just. There’s so much wrong with the situation, but like. To not perform nondestructive testing on the hull?? To ignore visible defects on a supplied material??

Metastable states of floating crystals

Magnetocapillary interactions between particles allow self-assembly of floating crystals along liquid interfaces. For a fixed number of particles, different states with different symmetric characteristics, called metastable states, coexist. Various pioneering works have observed the existence of metastable states in floating crystals. As different states coexist, it is difficult to control the formation of specific structures. However, controlling the formation of metastable states is a key ingredient to functionalize such assemblies, paving the way for self-assembling microrobots for example. The way to control the state of a floating crystal has never been studied before.

Carbon "pack bonds" with nearly EVERYTHING

Metallic bonds are "not like other bonds"

Working with gold is like working with a golden retriever