LED Light Bulbs | Bonded Fin Heat Sink | Production By Liquid Metal Forging

LEDs won’t burn your hand like some light sources, but they do produce heat. All light sources convert electric power into radiant energy and heat in various proportions. LEDs generate little or no IR or UV, but convert only 20%-30% of the power into visible light; the remainder (70%) is converted to heat that must be conducted from the LED die to the underlying circuit board and heat sinks, housings, or luminaire frame elements.

01-Light Emitting Diodes - LED - high powered lighting

Term: Heat Sink:

Thermally conductive material attached to the printed circuit board on which the LED is mounted. Myriad heat sink designs are possible; often a “finned” design is used to increase the surface area available for heat transfer. For general illumination applications, heat sinks are often incorporated into the functional and aesthetic design of the luminaire, effectively using the luminaire chassis as a heat management device.

01-LED bulbs - LED flashlight - LED light bulbs

Why does thermal management matter?

Excess heat directly affects both short-term and long-term LED performance. The short term (reversible) effects are color shift and reduced light output while the long-term effect
is accelerated lumen depreciation and thus shortened useful life. If heat is allowed to build, it can damage parts causing them to dim and lose efficiency.

01-heat sink thermal resistance - heat sink material - LED lights - bonded fin heat sink

Manufacturing Methods:

In liquid metal forging , sometimes called squeeze casting process, molten metal is poured directly into the bottom die. Then the top die is forced down to forge the part as that in a conventional forging operation.

01- liquid forging - liquid metal forging - squeeze casting

The metal solidifies rapidly under considerable pressure in the range of 27.5 to 82.6 MPa depending on the work metal. With optimized process parameters, liquid metal forging parts have no internal porosity and a fine cast structure.

01-heat sink production - heat sink manufacturing - heat sink compound

Previous Heat Sink Manufacturing Methods:

1. Extrusion

2. Machining

3. Stampings

4. Castings

Types of LED Heat Sink produced:

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Plated Fin

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Pin Fin

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Radial Fin

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Speciality Heat Sink

Benefits of Liquid forged Heat sinks:

1. Improved thermal performance

Rapid heat transfer delivers more lumens/ watt and enhances the LED lifespan.

• Aluminium wrought alloys conduct heat faster than cast alloys used in die casting.  Also by incorporating a copper base, the heat sink achieves 4 times better thermal conductivity.
• Intricate fins and pins deliver a higher aspect ratio, increasing the surface area for ambient heat transfer. With no centre core, heat removal by convection is also improved.
• Porous-free microstructure eliminates air pockets for rapid, continuous heat transfer through the heat sink to the surroundings.

2. Flexible Design

The key to an effective LED heat sink design is to be able to balance both maximisation of heat sink surface area and form factor constraint of light fixtures. Each custom LED lighting design involves the concept of efficiently transferring as much heat as possible away from the LED chip. With a high aspect ratio and the ability to create 3D designs as a single piece, liquid forging is a highly scalable manufacturing process, allowing the creation of intricate heat sinks made of composite materials such as copper and aluminium in a single step.  The fins of the heat sink can be combined with a copper base to create a radial heat sink with improved design and better thermal conductivity.  The process allows heat sinks and light fixtures to be formed as a single piece, minimising assembly costs, and improving thermal efficiency.

3. Enhanced finishing

The heat sink can be anodised for a better finishing, which further improves thermal performance by an additional 10 – 15%.

Features of LED heat sink by Liquid metal Forging:

1. High aspect ratio

2. Enhanced Heat Dissipation

3. Flexible Design

4. One step manufacturing with light fixture

5. Minimum Porosity

6. Anodised Finishing

7. Enhanced Aluminium alloy conductivity

Advantages:

(i) Elimination of micro porosity (shrinkage and porosity), due to the effect of solidification under pressure.

(ii) Improvement in product surface finishing due to high direct pressure into mould surface.

(iii) Production using Aluminium series materials

(iv) Multi cavity possible

(v) Near net shape process

(vi) High aspect ratio features

Limitations:

(i)  Variation in z‐axis thickness control

(ii) Mechanical structure (elongation)

Nano-Nuclear Batteries | Beta-Voltaic Power | Tritium Based Energy

Long-lived power supplies for remote and even hostile environmental conditions are needed for space and sea missions. Nuclear batteries can uniquely serve this role. In spite of relatively low power, the nuclear battery with packaging can have an energy density near a thousand watt-hours per kilogram, which is much greater than the best chemical battery. It would reason that small devices would need small batteries to power them.

01-Nano-Nuclear Batteries - thermoelectric devices - thermophotovoltaics

The world of tomorrow that science fiction dreams of and technology manifests might be a very small one. Tritium is a radioactive isotope of hydrogen that typically is produced in nuclear reactors or high energy accelerators. It decays at a rate of about five percent per year (half of it decays in about 12 years). It gives off radiation in the form of a beta particle. Tritium will bind anywhere hydrogen does, including in water, and in plant, animal and human tissue. It cannot be removed from the environment once it is released. Tritium can be inhaled, ingested, or absorbed through skin.

01-Nuclear batteries -, Direct charge nuclear -  betavoltaic effect

Moreover, radioactive isotopes are available on the market for reasonable prices ($1000) and low power electronics are becoming increasingly more versatile. Therefore, nuclear batteries are commercially relevant today.

Symbol: H (H-3)
Atomic Number: 1(Protons in Nucleus)
Atomic Weight: 1(naturally occurring H)

01-Deuterium-Tritium-Nuclear-Fusion

What is Tritium?

Tritium is the only radioactive isotope of hydrogen. The nucleus of a tritium atom consists of a proton and two neutrons. This contrasts with the nucleus of an ordinary hydrogen atom (which consists solely of a proton) and a deuterium atom (which consists of one proton and one neutron). Ordinary hydrogen comprises over 99.9% of all naturally occurring hydrogen. Deuterium comprises about 0.02%, and tritium comprises about a billionth of a billionth (10-16 percent) of natural hydrogen.

What is Isotope?

An isotope is a different form of an element that has the same number of protons in the nucleus but a different number of neutrons.

01-tritium nuclear energy - tritium based energy - life batteries

Alpha radiation:

Alpha particles are Helium nuclei (2 protons and 2 neutrons) .  These particles are relatively heavy and have poor penetrating power being over 90% blocked by a sheet of paper.

Beta Radiation:

Beta radiation (high speed electrons or photons) can penetrate paper.

Gamma Radiation:

Gamma radiation which can penetrate Aluminium.

01-tritium beta energy - tritium battery - nano tritium battery

How to produce a Tritium?

Tritium can be made in production nuclear reactors, i.e., reactors designed to optimize the generation of tritium and special nuclear materials such as plutonium-239. Tritium is produced by neutron absorption of a lithium-6 atom. The lithium-6 atom, with three protons and three neutrons, and the absorbed neutron combine to form a lithium-7 atom with three protons and four neutrons, which instantaneously splits to form an atom of tritium (one proton and two neutrons) and an atom of helium-4 (two protons and two neutrons).

01-tritium watches - tritium uses - tritium applications

Direct Radio Isotope Converts:
Radioisotope power conversion, in which the energy from the decay of radioisotopes is used as a power source, allows powering of applications which are unsuited to power sources such as photovoltaics or generators or to batteries. These applications are typically remote, not accessible to any external energy source (including sunlight), and often must last between 5 to 50 years. They include not only space, but also small power sources for biomedical uses. Radioisotope thermal generators (RTGs) are often used to convert the energy from the radioisotope by, converting it to heat, and then converting the heat to electricity via either a thermoelectric device, or thermophotovoltaics (TPV). Alternately, the radioisotope may be directly converted into electricity via betavoltaics, in which the energy from a beta particle creates electron holes pairs which are collected and used to generate power similar to a solar cell.