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Science, Maths & Technology
Pore-free die casting (active atmosphere casting)
Porosity is almost eliminated by the injection of an ‘active gas’ into the die cavity, prior to molten metal being piston forced into the cavity at high pressure. The gas combines chemically with the metal to form a finely dispersed solid casting.
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Science, Maths & Technology
How can scientists fight the tide of "fake news"?
"Fake news" is as much a problem for scientists as politicians. Crispin Maslog calls for an end to propaganda dressed up in lab coats.
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Science, Maths & Technology
Acurad process
Similar to high pressure die casting, but has wider gate to reduce turbulence, and a secondary plunger fitted inside the primary plunger. Pressure is applied to the molten metal forcing it through the gate and into the die cavity. The inner plunger operates, seconds after the primary plunger, ensuring any pores are filled, hence reducing ...
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Science, Maths & Technology
Vertical high pressure die casting
Molten metal is poured slowly into a shot chamber situated at the top of a drive cylinder that’s slightly tilted off vertical. The drive cylinder is moved back to vertical, and raised to a position at the base of the die. Pressure is applied to the shot piston so that the molten metal is forced vertically into the die cavity, and left to ...
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Money & Business
Is Huawei's low-key approach the secret of its success?
A visit to the Huawei campus finds a company open to naps in the office but against bombast. It's a formula that appears to be working.
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Science, Maths & Technology
Low pressure die casting (counter-pressure casting)
Low pressure air is introduced into a sealed furnace holding a tank of molten metal. The metal feeds up slowly through a riser tube and into the die cavity. Once the casting has solidified in the die, air pressure is released, allowing any residue molten metal still in the riser to fall back into the tank for recycling. When cooled, the casting ...
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Money & Business
Banks as utilities and the future of payments
In a wide-ranging discussion, Ecobank's Edward George shares his personal views about the future of banks, and digital strategy across African markets.
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Science, Maths & Technology
High pressure die casting
Molten metal is forced into a metal die at a high pressure. There are two main types: “cold-chamber” and “hot-chamber” processes.
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Science, Maths & Technology
Gravity die casting
Molten material is gently poured into a mould, using only the forces of gravity, then left to solidify.
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Science, Maths & Technology
CLA – Hitchiner process
A vacuum is applied to a hollow investment mould sealed within a chamber, causing molten metal to rise upwards into the hollow. The vacuum is released when the metal has solidified. Chandler-Lamb were the originators, and Hitchiner is the company.
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Science, Maths & Technology
Ceramic mould casting
Ceramic slurry is poured over a relief pattern and left to solidify, forming a cavity mould in the shape of the component to be cast. Cope and drag parts are produced. Each ceramic part is hardened by high temperature firing, then fitted together to make one hollow mould in which to cast the molten metal.
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Science, Maths & Technology
Resin shell casting
A thin shell of resin-bonded sand is formed around a heated metal pattern. Separating the shell from the pattern and clamping it to a mating shell forms a complete mould into which metal can be cast.