There are many types of static and dynamic tests, such as compression, tensile, shear flexure, fatigue, and fracture. There are many things to be considered while choosing a testing systems. It is already mentioned what are the different types of tests for any material. The second thing that you should know is determining testing specimens. You’ll have to check its configuration, size, shape, and material. You should also know what are ultimate test loads, ultimate strain-extension & compression, and strain measurement. Grip selection is one of the most important thing. For a successful gripping solution, the specimen must be held. Instron grips must be choose wisely. Two of the major problems that is faced while testing a specimen is slippage and jaw breaks. Generally, jaw breaks occur because of the sample inside the grip is either damaged by too much clamping force, or serrated faces biting too deep. There are three ways to prevent jaw breaks. First is screw action grip. It means that the operator must not use too much force when tightening the sample. Using a torque wrench or pneumatic grips are a much better. Other thing is pneumatic grips, that can be done by dropping the pressure, but not to the point the specimen get slipped. And, the last thing is serrated face. Changing the faces that have more serration per inch. The idea here is to softening the bite and preventing damage to the sample. Once the gripping is done, you’ll have to select load cell. It is used to measure the force that is getting experienced by the sample. It monitors, reports and control the force exerted on the specimen. Choosing a proper load cell is important and there are few things to be considered when choosing a load cell. Some of these characteristics are capacity, accuracy, repeatability, off-set loading error, non-linearity, compensated temperature range, temperature effects on zero and sensibility, life time, overload capacity, and off-axis stiffness. Next in the line is extensometry selection. It is important to know that every mechanical system that is subjected to a force will deform, it may be slight but there will be some change. This deformity can affect the test results. To check and calculate the figures, extensometers are used. There are two main types of extensometer. Contact extensometers e.g. clip-on, long travel, high-temperature, etc. And, non-contact extensometer e.g. laser and video. Non-contact extensometers are relatively better that the other one. It has several benefits such as no influence on the test specimen, no problem with knife-edge slip, no error due to inertia of moving parts. Also, there is no possibility of damage due to energy released at the time of failure. There are few other things to consider such as optimizing specimen alignment, accuracy, resolution and precision, data rate and bandwidth, software function and performance. These are the things that you should consider to have a more accurate and successful testing of any specimen by using instron test machine. Apart from these things, there can be other factors that you might need to take in account at the time of testing.
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