Materials testing is a respected and established technique that is used to ascertain both the physical and mechanical properties of raw materials and components. It can be used to examine almost anything from human hair to steel, ceramics, or composite materials.
In order to address the challenges posed in the testing of a wide range of materials, AMETEK Test & Calibration Instruments can offer an extensive array of high-performance materials testing machines. These machines have been developed to conduct accurate, repeatable force measurements between 0.1 N and 300 kN (0.0225 lbf – 67,443 lbf). Elongations of between 1 micron and 2.5 m (98.4 inches) can be measured, depending on the machine being used.
Common testing capabilities include the following:
- Deformation Strength
- Rupture Strength
- Shear Strength
- Adhesion Strength
- Bond Strength
- Delamination Strength
- Tear Resistance
- Creep and Stress Relaxation
- Crush Resistance
- Coefficient of Friction
- Elastic Limit
- Flexure / Bend Strength
- Break Load
- Tensile Strength
- Young’s Modulus
- Ductility
- Toughness
- Puncture Strength
- Compression
- Elongation
- Peel Strength
Applications of Material Testing Machines
Materials testing machines are ideal for use in production, quality control, education, research or laboratory settings. Due to the extensive testing capabilities mentioned above, these devices can be used in a diverse range of applications within markets such as:
- Electronics
- Automotive
- Paper and Board
- Medical
- Building Materials
- Metals
- Plastics
- Textiles
- Rubber
- Packaging
- Pharmaceuticals
- Wood
Different Types of Material Testing Machines
Universal materials testing machine is configurable for a range of applications. This can be accomplished by selecting the appropriate load cell, sample holder grip, materials testing software (optional), and any required accessories such as thermal cabinets, high-temperature furnaces, or extensometers.
The product range from Lloyd Instruments is arranged by maximum load frame, with thirteen ‘Plus’ machines covering the range from 1 kN to 300 kN (225 lbf to 67,443 lbf). At the core of each materials testing system is a robust, high stiffness load frame while advanced electronics guarantee that data collection is accurate, exceeding the requirements of BS EN 7500-1 and ASTM E4.
Single column configurations can be utilized for lower force instruments, with dual columns being suitable for higher force requirements.
Single Column Test Machines
Single column instruments are suitable for applications that need force between 1 and 5 kN (225 and 1,124 lbf). These test machines are bench mounted and offer a substantial working area.
Dual Column Test Machines
Dual column instruments can be provided in bench-mounted (5 to 50 kN, 1,124 to 22,841 lbf) or floor-mounted versions (100 to 300 kN, 22,481 to 67,443 lbf).
Bench-mounted instruments are well suited for routine testing or quality control, as well as being able to accommodate complicated, multi-stage tests within the mid force range. Floor-mounted materials testers are heavy-duty test machines that are robust and feature a generous working area.
Load System Compliance Compensation
Load chain compliance (or stiffness) compensation coupled with advanced frame design allows for extension errors of less than 5 microns at full load. This low margin of error can be achieved for a wide range of flexural and compression tests, with no need to use an extensometer.
In many cases, instrument deformation is minuscule when compared to that of the sample, so the error is not noteworthy. Stiffness compensation improves measurement accuracy within applications where the system deformation is a more substantial portion of the whole measurement.
High Elongation Sample Testing
Extended height frames can be acquired for all single and dual column systems. These are suitable for testing high elasticity materials, or where samples are to up 2.5 m (98.4 inches) high (depending on the model in question).
Customized Material Testing Machines
Several materials testing applications need specifically adapted instrumentation. This could be due to the needs of the application itself, or even because the location where the equipment will be sited has limited space available.
In order to accommodate these diverse needs, Lloyd Instruments can create custom versions of its universal testing machines. Examples include testing machines that have additionally wide distance between columns or shortened versions which can fit into especially small laboratory spaces.
Fixtures and Accessories for Material Testing Machines
Lloyd Instruments can provide a diverse array of accessories or fixtures for its material testing machines. These include:
Grips and Fixtures for Material Testing Machines
Universal materials testing machines can be adapted into being highly specialist testers for a wide range of applications. This is possible with the addition of a selection of probes, standard grips, fixtures, and flexural jigs. Lloyd Instruments can provide grips and fixture offerings in an array of sizes, styles, gripping surfaces, and capacities including:
- Wedge action grips for rigid samples
- Self-tightening grips to reduce operator fatigue
- Bollard grips for wire, rope, thread, and fiber testing
- Vice action grips for films or semi-rigid materials
- 3- and 4-point bending jigs
- Compression platens available in many sizes
- Pneumatic action grips for faster sample clamping
Non-standard applications can usually be accommodated via the design and implementation of a specialist fixture or jig to hold the sample in question without the need to modify the testing machine.
Sample holding design solutions have been extremely varied, ranging from full robotic needle/syringe testbeds designed to measure needle sharpness and syringe performance to specialist jigs designed for testing fiber-optic cable strength.
A custom solution has even been developed with a spaghetti and noodle compression attachment for measuring the thickness of the cooked product to calculate sample compressibility and other parameters.
Load Cells for Material Testing Machines
Load cells can be provided in capacities ranging from 5 N to 300 kN, depending on the machine being used and the test being performed. These are accurate, self-identifying full bridge strain gauged load cells that have been developed to meet international standards for load cell accuracy.
Extensometers for Material Testing Machines
Plug and play extensometers have been designed to accurately measure elongation, determining results such as yield, modulus, proof stress, and more. These include:
- Contacting strain gauge type for rigid materials (for example metals)
- Non-contacting laser type for high elongation materials (for example plastic film)
- Automatic contacting long travel type for rubbers and elastomers
Elevated and Low-Temperature Materials Testing
Elevated and low-temperature materials testing is commonplace in a diverse range of industries. Furnaces and thermal chambers can be provided for testing between -70 °C and +1,200 °C. These furnaces and chambers can be software controlled if required.
Compression Cages for Material Testing Machines
Compression cages are built for the testing of very large samples and awkwardly shaped full assemblies, for example, a whole car seat. The test machine must be mounted above the cage to allow the complete range of compression tests to be undertaken with samples that are wider than 400 mm.
These assemblies are made from aluminum to ensure robustness and are constructed to specific customer specifications. The cage sides can either be open or shielded with polycarbonate panels or wire mesh. Additionally, compression platens can be integrated into the frame and mounted on guide bearings to ensure optimal alignment.
Testing and Control Software for Material Testing Machines
All instruments can function as stand-alone units, but there is an ever-increasing requirement for automated operation and software control, often via a PC. All of Lloyd Instruments’ ‘Plus’ materials testing machines have PC control functionality via the company’s NexygenPlus test and control software.
The NexygenPlus software application provides a wide-ranging library of predefined test setups that are based on international standards. It can be used to set up routine tests, or to create a more complex multi-stage test, allowing the operator to monitor and control every aspect of the system from one, intuitive user interface.
The software allows for quick, powerful, and reliable testing as well as easy control of a range of data analysis features. NexygenPlus is provided as a full, comprehensive package that does not require any additional modules. It includes:
- User interface customization facility
- A comprehensive suite of test setups
- Video and still picture capture system
- Security and audit trail utility
- Data export utility for connection to LIMS and SPC packages
- SPC trend and histogram charts
- Complete library of standards
Test creation wizards are included to allow for more specialized testing. These include tension/compression tests, tear and peel tests, flexural tests, cycling tests, friction tests and a user-configurable test suitable for multi-stage testing. Not only that, but the software supports National Instruments’ data acquisition cards which allows for easy communication with external equipment.
Summary
Lloyd Instruments’ materials testing machines enable a huge range of materials testing applications to be conducted across a wide array of sectors. Lloyd Instruments’ material testers can be used to assist with:
- Developing world-class products via extensive product development testing
- Contributing to cost effective manufacture of products to the highest quality
- Demonstrating the superior performance of products
- Ensuring that products are manufactured in line with international or industry standards
- Verifying supplier specifications
- Providing fully traceable test results
This information has been sourced, reviewed and adapted from materials provided by Lloyd Instruments Ltd.
For more information on this source, please visit Lloyd Instruments Ltd.