What is tensile testing and what is it used for?
The variety of materials used by mankind is huge. Most often, these are products of deep processing of natural raw materials, which are at the service of our comfort, health and safety. The choice of material for the creation of any structure or mechanism depends in a key way on its mechanical properties, such as strength and extensibility. This becomes especially important for the military industry, where the health and lives of not only the military, but also the many civilian people they protect depend on the reliability of structural materials. That is why society has an interest in the military industry having access to the most advanced technologies and being able to produce and use the best quality equipment.
Metal tensile testing is one of the most important mechanical control methods used. They allow you to determine how strong the material is and how much it can lengthen. Any new material must undergo this kind of control before use. Special tensile testing machines are designed for this purpose. During the test a force is uniformly applied to the material, stretching it until it breaks, during which the change in the geometry of the sample under the action of mechanical stress is measured. The load and the reaction of the material to it are measured using special sensors. From the tensile testing of material samples, you can learn a lot about its strength required for prediction of its behavior under the influence of force. This will give its ultimate tensile strength, plasticity, which is determined by the elongation of the sample and the narrowing of its cross section. The obtained results are used in the selection of new materials for specific applications, as well as in the quality control of structural materials during their in-line production. This process is generally accepted in the development and production of materials, its advantages also include the availability of many standard procedures and the commercial availability of appropriate equipment to perform them.
Tensile sample preparation using tensile testing machine
Imagine that you are stretching two sticks made of the same material but of different thicknesses. It is clear that it is easier to stretch the one that is thinner. And it is easier to destroy it. That is, the result of the tensile test depends not only on the properties of the material, but also on the shape of the specimen for tensile testing. That is why the shapes of such samples are standardized. There are generally accepted standards for tensile samples of many different sizes, dumbbell-shaped: flat or round, differing in length and cross-sectional area. The wider ends of such samples are fixed in the grips of the tensile sample testing machine, tensile occurs axially, i.e. along the axis of the sample, and the main changes in shape occur in the thin part of the tensile sample, in which it eventually breaks. Given this, the accuracy and reliability of the process of manufacturing such samples becomes one of the main factors in obtaining reliable reproducible test results. In addition, the homogeneity of the material and the absence of any damage and scratches on the surface of the tensile specimen are important factors.
Why is the accuracy of the production of tensile samples important for the US military?
The US military is tightly regulated. The statutes and rules by which the military operates are written with the blood of their predecessors and the lives of those civilians whom they could not protect. That is why the reliability of the equipment and structures used by the military must be at the highest level. Therefore, the accuracy of determining the mechanical properties of structural materials is of critical importance.
Where in civilian life, for example, an unreliable fastening of a car wheel can lead to significant troubles related to the loss of time and possibly the health issues for one or more people, the unreliability of such a fastening in a combat vehicle threatens not only life and health to its crew, which may contain up to a dozen soldiers, but also to their colleagues who were counting on the execution of the task by this unit, and with the rest, to the civilian population who will find themselves without the necessary protection due to a possible disruption of the military operation.
Not to mention such areas of military development as the creation of armor for combat vehicles, protective plates for bulletproof vests, and transparent armor for airplane windows. Their reliability is directly based on the use of materials with precisely defined mechanical properties. With the advent of firearms in the world, there is still a competition between the bullet and the armor. This competition is worth the lives of many warriors and there is no room for error.
As for the importance of the secrecy of materials and their properties for the US military, we can mention an example of such a situation, when the US government recently agreed to transfer Abrams tanks to the Armed Forces of Ukraine. However, such a transfer became possible only with the condition of removing from these machines super-strong armor made of depleted uranium and replacing these sheets with other armor, also reliable, but without such a high level of secrecy for the composition of the material. This composition is not still disclosed not only to allied military personnel from Ukraine, but also to US NATO partners.
Therefore, a high class of developments for the US military will require manufacturers to strictly comply with regulatory requirements that guarantee equipment reliability and information protection requirements that ensure the necessary level of secrecy. Regulatory compliance will require product testing. By subjecting materials to stress and other environmental hazards under controlled conditions, the manufacturer will be able to determine whether their products meet the high standards of the US military.
Ways to achieve a bulletproof process for Tensile Testing
The accuracy of reproducing the standard dimensions of tensile samples is achieved by using milling and turning machines with software control, which are capable of producing parts with an accuracy of several micrometers. Such a tool should be available at every enterprise that investigates the mechanical properties of materials, because it will guarantee the preservation of tensile samples from possible surface damage during transportation. The presence of such a device in the laboratory for testing mechanical properties will also provide an opportunity to control the waste from the production of tensile samples, that is, cuttings, shavings, and sawdust. The fact is that some of them can be harmful to the environment, and the best way to dispose of them is can be found at the enterprise where they were manufactured. Especially in the military field, the composition of materials can be a state secret, so the use of third-party contractors to create samples for tensile testing in this case is extremely dangerous.
There are two lines of equipment for creating flat and round specimens for tensile tests, respectively, milling machines for flat specimen preparation and lathes for round specimen preparation. The use of modern equipment ensures the reproducibility of the geometric shapes, and accordingly, allows you to conduct reliable tensile tests in compliance with the strict standards of the US Army level.
TensileMill CNC Inc.’s Ultimate Tensile Sample Preparation Equipment is ideal for meeting these requirements. The manufacturing company supplies equipment for both flat specimen preparation and round specimen preparation. The peculiarity of these lines is that they can be operated by personal of any skill level, obtaining results that meet the highest standards of production tests. TensileMill’s long-term experience guarantees the reliability of work and timely service of the supplied equipment. This is the reason why thousands of manufacturers, educational institutions, government agencies, civil and military inspection laboratories choose us.