Graphene | Graphene Technology | Graphene The Material Of The Future | Graphene Review | Graphene Properties | Graphene Production

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The graphene is a substance which has a single-layer crystal lattice of carbon atoms, which is unusual since it is different from all of the materials of its kind. Several researchers have identified a way of making this substance, which allows them to use it in various fields and especially for the high-speed electronic devices.

Graphene Definition:

Graphene is defined as a one atom thin sheet of carbon atoms arranged in a Hexagonal format or a flat monolayer of carbon atoms that are tightly packed into a 2D honeycomb lattice.

History:

In October 2010, two University of Manchester (U.K.) scientists, Andre Geim and Konstantin Novolselov, were awarded the 2010 Nobel Prize in physics for their research on graphene. Graphene is a one-atom-thick sheet of carbon whose strength, flexibility, and electrical conductivity have opened up new horizons for high-energy particle physics research and electronic, optical, and energy applications.

Graphene properties:

Graphene oxide, a single-atomic-layered material made by reacting graphite powders with strong oxidizing agents, has the ability to easily convert into graphene a low-cost carbon-based transparent and flexible electronics.

Graphene Oxide:

Graphene oxide has been known in the scientific world for more than a century and was largely described as hydrophilic, or attracted to water. These graphene oxide sheets behave like surfactants, the chemicals in soap and shampoo that make stains disperse in water.

Mechanical Properties:

Young’s Modulus:

1. Graphene sheets stack to form graphite with an interplanar spacing of 0.335 nm, which means that a stack of 3 million sheets would be only one millimeter thick.

2. Graphene is a Zero Gap Semiconductor. So it has a high electron mobility at room temperature. It’s a Superconductor. Electron transfer is 100 times faster then Silicon.

3. Graphene has a record breaking strength of 200 times greater than steel, with a tensile strength of 130GPa.

4. Graphene can be used to create circuits that are almost superconducting, potentially speeding electronic components by as much as 1000 times.

5. Graphene electrodes used in lithium-ion batteries could reduce recharge times from two hours to about 10 minutes.

Graphene Production:

Chemical Vapor Deposition (CVD) and Molecular Beam Epitaxy (MBE) are two other potential routes to Graphene growth.

Applications:

• New devices like Touch screens, Micro Displays and Monitors
• Chip Making, Circuit Designs
• Solar cells
• Micro Fuel Cells
• Air Bag Deployment Systems and Gyroscopes in Car Electronic Stability Control
• Pressure Sensors, Micro Tips & probes

MECHANICAL TESTING | Mechanical Testing of Materials | Mechanical Testing of Metals | Mechanical Testing of Welds | Mechanical Testing Facilities | Load & Tensile Test | Mechanical Testing Machine

• Tensile Test

A tensile test, also known as a tension test, tests a material’s strength. It’s a mechanical test where a pulling force is applied to a material from both sides until the sample changes its shape or breaks. It’s is a common and important test that provides a variety of information about the material being tested, including the elongation, yield point, tensile strength, and ultimate strength of the material. Tensile tests are commonly performed on substances such as metals, plastics, wood, and ceramics.

Tensile testing systems use a number of different units of measurement. The International System of Units, or SI, recommends the use of either Pascals (Pa) or Newtons per square meter (N/m²) for describing tensile strength. In the United States, many engineers measure tensile strength in kilo-pound per square inch (KSI).

• Tensile test with electronic extensometer

This instrument is to be used on Tensile or Universal testing machines to find out Proof stress & Young’s modulus values. In case of many brittle materials such as high carbon steels, alloy steels, light aluminium & magnesium alloys, it is difficult to get yield values. For such materials stress corresponding to a certain allowable amount of plastic deformation is termed as proof stress say 0.1% or 0.2% proof stress. The measuring range is up to 5mm & resolution is 0.001mm.

• Tensile testing at elevated temperature.

High temperature tensile testing is a procedure to test the properties of a material at above room temperature. It will determine the following parameters:

• Tensile strength (breaking strength)
• Yield strength
• Elongation
• Reduction of area

Specialist testing, measurement and control equipment is required to perform this test.
The results of such a test will provide a good indication of the static load bearing capacity of the material and therefore establishes the suitability of a material for its intended purpose.

• Tensile test on Tor steel Bars

TOR steel is one of the best grade of steel used in concrete reinforced. It’s a kind of high adherence steel. Other types of steel are used for less resistance concrete. Thermo mechanically Treated (TMT) bars are a type of corrosion resistant steel reinforcing bar used in concrete construction.

• Bend test on plates

A bend test is used to determine whether a specific piece of metal in question will break or fracture under pressure. This is important in the construction of any project using metal, otherwise the building or the item being made could collapse from the immense pressure exerted on it. Every piece of metal made cannot be tested, therefore certain pieces are tested and if they pass, the other pieces are made using the same process. The results of a bend test are reported differently depending on the type of material tested. There is no standard method for reporting the durability that applies to all materials, rather each group has its own set by which it is judged and compared to other metals in that group.

The bend test is essentially measuring a metal’s ductility. Ductility defines how easily a metal can bend without breaking. The higher the ductility of a metal, the more it can bend without breaking or becoming deformed from its original shape. This is important because certain metals must handle pressure without snapping yet still be ductile enough to bend slightly and not lose their support or shape. Copper and steel are two metals that have a high ductility and do well under pressure.

• Bend test on pipes

Bending tests are carried out to ensure that a metal has sufficient ductility to stand bending without fracturing. A standard specimen is bent through a specified arc and in the case of strip, the direction of grain flow is noted and whether the bend is with or across the grain.

• Bend Test on Tor steel

The purpose is to make certain the weld and the base metal are properly fused, and that the weld metal and the heat affected zone (HAZ) have appropriate mechanical properties

• Re-Bend test on Tor steel

The purpose of re-bend test is to measure the effect of strain ageing on steel. Strain ageing has embrittlement effect which takes place after cold deformation by diffusion of nitrogen in steel. Hence, there is limitation stated in some design codes to restrict the nitrogen content of steel to 0.012%.

• Nick Break Test

The NICK-BREAK TEST is useful for determining the internal quality of the weld metal. This test reveals various internal defects (if present), such as slag inclusions,  gas  pockets,  lack of  fusion,  and  oxidized  or burned metal. To accomplish the nick-break test for checking a butt weld, you must first flame-cut the test specimens from a sample weld.

Vision Gauge Digital Optical Comparator | Optical Comparator Measurement | Digital Optical Comparator Machine

The Vision Gauge Digital Optical Comparator is "The Fastest, Easiest, Most Accurate Way to Compare a Part to a CAD File. Vision Gauge Digital Optical Comparators are very robust. They are perfect for both the shop floor and the Quality Control lab. Standard 12" travel X-axis stage with 0.5 micron resolution encoder and protective bellows around the 6" travel Y-axis column. All 3 axes (X, Y and Z) have high-accuracy crossed roller movements for optimal linearity and positional repeatability and high load carrying capability. Hard chrome plated X-axis stage, made of hardened tooling steel and with dual industry-standard dovetail grooves for easy part fixturing.

Vision Gauge Digital Optical Comparators are complete, ready-to-run Windows-based solutions and  are  delivered network-ready. They are available in both horizontal and vertical configurations. They have industry standard dovetail mounting grooves for easy part fixturing.

Vision Gauge Digital Optical  Comparators are available  with transmitted (i.e. back) and / or reflected (i.e. front) illumination.  All  illumination  is  LED-based for very stable and repeatable illumination  conditions  over  a  very  long  life  (no  more  bulbs  to replace!). Furthermore, the illumination is programmable and computer-controlled. Everything is done through a single simple an d intuitive software interface.

Vision Gauge Digital Optical  Comparators have power focus. They are available in industry standard 5X, 10X, 20X,  50X  and 100X  optical configurations.  They are available in both single and multi-mag configurations.

Vision Gauge Digital Optical Comparators and extremely easy to use. They are a "drop in" replacement for traditional optical comparators. An optional high-resolution LASER module is also available for depth & height measurements. Motorized fixtures and extended travels are also available.

Benefits:

• Produce a very high contrast image with very sharp edge profiles so that there is no problem viewing it in full daylight.
• Are much more accurate
• Allow the user to be much more productive and get more work done with a single machine
• Have "Auto Pass / Fail"
• Can compute and display the part’s deviation from nominal and compare it to bi-directional tolerances
• Work directly with the CAD data so that no overlays / templates / Mylars are required
• Can be used to collect images (either with or without the CAD data overlay and with or without annotations), measurements and data .
• Can also carry out fully automated measurements (like a video CMM)
• Have a smaller footprint and use less floor space
• Can be moved much more easily and without requiring re-calibration (i.e. “rolling cart” configuration is standard)
• Have a much greater optical depth of field, i.e. “everything is in focus all at once”
• Have a longer optical working distance ( i.e. more clearance between the part and the lens)
• Allow you to compare a part to its CAD data beyond the optical field-of-view ! (because the CAD data tracks the part and follows the stage motion )
• Have LED illumination for very stable illumination over a 10 year life. No more bulbs to change