Quantum Tunnelling Composite (QTC) | A Pressure Switching And Sensing Material Technology | Electro Mechanics Components

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QTC is a composite made from micron-sized metallic filler particles (Silicone Rubber) mixed into an elastomeric matrix. Quantum tunnelling composite is a flexible polymer that exhibits extraordinary electrical properties. In its normal state it is a perfect insulator, but when compressed it becomes a more or less perfect conductor and able to pass very high currents.

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History:

First produced in 1996, QTC is a composite material made from conductive filler particles combined with an elastomeric binder, typically silicone rubber. The unique method of combining these raw materials results in a composite which exhibits significantly different electrical properties when compared with any other electrically conductive material.

01-QTC pills-variable resistor-applications of QTC using pills-touch switches

Types of QTC:

1. Elastomeric (Material: Silicone Rubber) (The particle move close together)

2. Ink / Coating Solvent or Aqueous Polymer

3. Granular Sensors

Working of Quantum tunnelling composite:

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QTC usually comes in the form of pills or sheet. QTC pills are just tiny little pieces of the material. The sheets are composed of one layer of QTC, one layer of a conductive material, and a third layer of a plastic insulator. While QTC sheets switch quickly between high and low resistances, QTC pills are pressure sensitive variable resistors.

Application:

01-QTC touch Screen-pills-force or pressure sensors-quantum tunneling composite screen-pressure sensitive variable resistors

– Touch switches (sheet)
– Force/pressure sensors (pills)
– Motor speed control using force (pills)

Benefits:

  • QTC is a pressure/force sensing material. It can be easily integrated into existing products to enable force sensing opportunities and solutions.
  • Product surfaces can be incorporated, coated or impregnated with QTC to impart the properties of force sensing into or onto the host surface.
  • QTC material can be formed or moulded into virtually any size, thickness or shape, permitting redesign of product interfaces and providing improved ergonomics, aesthetics and user comfort.
  • QTC is an enabling technology which is simple and reliable to use.
  • QTC material is durable – it has no moving parts to wear out.
  • QTC material is mechanically strong.
  • QTC material can be made to withstand extreme temperatures limits.
  • QTC material is versatile, both electrically and physically e.g. Its range and sensitivity can be altered. QTC material is also intrinsically safe – the material is a contactless switch, ideal for sparkless operation.
  • QTC material can be directly interfaced to standard electronic and electrical devices.
  • QTC material and/or technology can be customized for customer requirements, applications and products.

Laser Cladding Technology | Laser Cladding Process | Laser Cladding Applications | Laser Welding | Laser Cutting | Laser Cladding Repair Services

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Laser Cladding is the process wherein the metal (powder/wire) is deposited on to another metal using a laser as heat source. It’s an alternative to traditional welding and thermal spray.

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This technology is similar to thermal spray in that it has an energy source to melt the feed stock that is being applied to a substrate. Where it differs is that it uses a concentrated laser beam as the heat source and it melts the substrate that the feed stock is being applied to. This results in a metallurgical bond that has superior bond strength over thermal spray. Additionally the resulting coating is 100% dense with no voids or porosity.

Working of Laser Cladding:

01-schematic diagram of Laser_Cladding_System_setup

The basic system is made up of a laser to generate the beam, a set of optics to direct and focus the beam, a powder feeder, and a part manipulator. The laser and optics stay stationary and the part is moved in relationship to the laser. The laser cladding systems are fully automated providing precise control of the coating (cladding) process.

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Advantages:

  • One of the advantages of the laser cladding process is the concentrated beam of energy from the laser. It can be focused and concentrated to a very small area and keeps the heat effected zone of the substrate very shallow. This minimizes the chance of cracking, distorting, or changing the metallurgy of the substrate. Additionally the lower total heat minimizes the dilution of the coating with material from the substrate.
  • Coating thicknesses can reach .125" (3.1mm) with carbides in one pass and can go to any thickness with other materials and multiple passes.
  • Because the feed stock is a powder, so there is a large variety of materials available including pure metals, alloys, or carbides. Further the development extensively with Inconel and Stellite alloys on a wide assortment of oil field applications.

Applications:

  • Optimal Part Design by Dissimilar Metal Deposition
  • Ideal for Repair & Restoration
  • Material Research & Development
  • Wear Resistance & Fatigue Life Improvements