Month: July 2014

Multi metal 3D printing

Any progress on interesting materials (read: not plastic) is welcome news.

Researchers have developed a 3D printing process that transitions from one metal or alloy to another in a single object. For example, they created a prototype of an improved telescope mirror mount. The part at the top near the glass mirror is made of a metal with low thermal expansion, so that it won’t shrink in space as much as most metals do. That prevents stress in the epoxy adhesive between the mirror and the metal. The bottom part of this mount is stronger stainless steel and could be connected to a stainless steel component of a spacecraft.


2023-04-04: Controlling the cooling is crucial to avoid weaknesses

While the printing process wastes less material and can be used to produce more complicated shapes than traditional manufacturing methods, researchers have struggled to grasp how to steer metal toward particular kinds of crystals over others.

This lack of knowledge has led to parts with complex shapes cracking prematurely thanks to their crystal structure. “Among the 1000s of alloys that are commonly manufactured, only a handful can be made using additive manufacturing”. The data depicted the push and pull between 2 kinds of crystal structures, austenite and delta ferrite, the latter being associated with cracking in printed parts. As cooling rates surpassed 1.5m kelvins per second, austenite began to dominate its rival. This critical threshold lined up with what the model foretold. The model can inform what cooling rates to select for the early solidification steps of the printing process. That way the optimal crystal structure would appear within their desired material, making metal 3D printing less of a roll of the dice.

Hamas strategy?

When the Muslim Brotherhood government fell, the military leaders cracked down. They sentenced 100s of the Brotherhood’s leadership class to death. They also closed 95% of the tunnels that connected Egypt to Gaza, where the Brotherhood’s offshoot, Hamas, had gained power. The Egyptian move was economically devastating to Hamas. Hamas derived 40% of its tax revenue from tariffs on goods that flowed through those tunnels. Hamas needed to end that blockade, but it couldn’t strike Egypt, so it struck Israel. If Hamas could emerge as the heroic fighter in a death match against the Jewish state, if Arab TV screens were filled with dead Palestinian civilians, then public outrage would force Egypt to lift the blockade. Civilian casualties were part of the point. “Make no mistake, Hamas remains committed to the destruction of Israel. But Hamas is firing rockets at Tel Aviv and sending terrorists through tunnels into southern Israel while aiming, in essence, at Cairo.”

The Gerontovetocracy

Germany’s graying society, it seems, is so cozy and settled that it resists anything threatening to upset the status quo. In the process, it has lost sight of the bigger picture.

increasingly, protest movements are formed by people on death’s door, who have nothing to lose and want to avoid change at any cost.

Procedural Universes

the state of procedural universes:

You’re building a blueprint. So say one of our artists will build something and that will take say a week. But what they get from that is every possible variant of that. So if you build a cat, you also get a lion and a tiger and a panther and things that you’ve never seen—kind of mutations beyond that