article icon
Digital & Computing
Spectre and Meltdown: What do you need to know about the chip security flaws?
The discovery of a security problem with chips in desktops, laptops, phones and tablets is a major headache for IT security, says Siraj Ahmed Shaikh.
article icon
Nature & Environment
Can eating seaweed and algae keep the world fed?
As the planet has ever-more mouths to feed, could increasing the consumption of seaweed and algae be the answer?
article icon
History & The Arts
Under the covers: The emerging critical sleep studies
Jennifer J* Moos responds to Michael Greaney's thoughts on how the science of sleep is portrayed in modern literature.
article icon
Education & Development
Interdisciplinarity: A collection
Bringing together the best of interdisciplinary resources from across OpenLearn – could an "Open" qualification be right for you?
article icon
Science, Maths & Technology
What does clay tell us about the possibility of life on Mars?
Dave Rotherey explains the implications of new research into the clay surface of Mars.
video icon
Science, Maths & Technology
Why has Donald Trump set his sights on the Moon?
The President has instructed NASA to build a camp on the Moon. It might be a better idea than trying to get straight to Mars, as this New Scientist short, sharp, science video explains.
video icon
Science, Maths & Technology
Hans Rosling: How to compare countries using statistics
Statistician magician, the late Hans Rosling shows you how to collate and animate the data of different countries in these short videos that depict our changing world.
article icon
Science, Maths & Technology
Laser cutting
Mainly used for precision cutting of materials with a low melting point. A finely focused laser beam locally heats the surface of the workpiece, vaporising and melting away material. Residue material is removed by induced vapor pressure, or by gas jets (gas-assisted laser cutting).
article icon
Science, Maths & Technology
Electrical Discharge Wire Cutting (EDWC) and Sawing (EDS)
In EDWC, sparks are generated between the electrically conductive material of the workpiece and a vertical cutting wire (the negative electrode that is constantly fed from a spool), debris is carried away by the dielectric liquid. Heat from the electrical discharge melts away material to form a slot (kerf). EDS is a similar process, but the ...
article icon
Science, Maths & Technology
Electrical Discharge Machining (EDM) and Grinding (EDG)
A workpiece made of electrically conductive material and a shaped tool are immersed in a dielectric fluid. Rapid pulses of electricity pass through the tool (+ve electrode) and the negatively charged workpiece, leading to a spark discharge. Plasma forms and, along with the sparks, vaporises the workpiece material removing material ‘chips’, which...
article icon
Science, Maths & Technology
Photochemical Machining (Photo-fabrication; Chemical milling)
A chemical etching process where material can be selectively removed from specific ‘unmasked’ areas of a pattern or image that was photographically reproduced onto the workpiece surface.
article icon
Science, Maths & Technology
Electrochemical Grinding (ECG)
An electrolyte is pumped into a small gap between the workpiece and a rotating abrasive grinding wheel. Metal is removed from the electrically conductive workpiece by electrochemical attack and abrasion. Protruding abrasive grit particles on the grinding wheel remove electrochemical oxidation from the surface of the workpiece.