ArticleslgStudy

engineering

Tensile testing

Tensile testing is a engineering topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Tensile testing rather than just read about it. In short: Tensile testing, also known as tension testing, is a fundamental materials science and engineering test in which a sample is subjected to a controlled tension until failure. Properties that are directly measured via a tensile test are ultimate tensile strength, breaking strength, maximum elongation and reduction in area.

Tensile testing — main illustration
Tensile testing — illustration

Key takeaways

  • Tensile testing belongs to engineering; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Tensile testing to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Tensile testing from memory before moving on to harder problems.

Reference excerpt

Tensile testing, also known as tension testing, is a fundamental materials science and engineering test in which a sample is subjected to a controlled tension until failure. Properties that are directly measured via a tensile test are ultimate tensile strength, breaking strength, maximum elongation and reduction in area. From these measurements the following properties can also be determined: Young's modulus, Poisson's ratio, yield strength, and strain-hardening characteristics. Uniaxial tensile testing is the most commonly used for obtaining the mechanical characteristics of isotropic materials. Some materials use biaxial tensile testing. The main difference between these testing machines being how load is applied on the materials.

Purposes of tensile testing Tensile testing might have a variety of purposes, such as:

Select a material or item for an application To understand state of degradation of cultural heritage (heritage science) and choose appropriate materials for conservation treatment. Predict how a material will perform in use: normal and extreme forces. Determine if, or verify that, the requirements of a specification, regulation, or contract are met Decide if a new product development program is on track Demonstrate proof of concept Demonstrate the utility of a proposed patent Provide standard data for other scientific, engineering, and quality assurance functions Provide a basis for Technical communication Provide a technical means of comparison of several options Provide evidence in legal proceedings

Tensile specimen

The preparation of test specimens depends on the purposes of testing and on the governing test method or specification. A tensile specimen usually has a standardized sample cross-section. It has two shoulders and a gauge (section) in between. The shoulders and grip section are generally larger than the gauge section by 33% so they can be easily gripped. The gauge section's smaller diameter also allows the deformation and failure to occur in this area. The shoulders of the test specimen can be manufactured in various ways to mate to various grips in the testing machine (see the image below). Each system has advantages and disadvantages; for example, shoulders designed for serrated grips are easy and cheap to manufacture, but the alignment of the specimen is dependent on the skill of the technician. On the other hand, a pinned grip assures good alignment. Threaded shoulders and grips also assure good alignment, but the technician must know to thread each shoulder into the grip at least one diameter's length, otherwise the threads can strip before the specimen fractures. In large castings and forgings it is common to add extra material, which is designed to be removed from the casting so that test specimens can be made from it. These specimens may not be exact representation of the whole workpiece because the grain structure may be different throughout. In smaller workpieces or when critical parts of the casting must be tested, a workpiece may be sacrificed to make the test specimens. For workpieces that are machined from bar stock, the test specimen can be made from the same piece as the bar stock. For soft and porous materials, like electrospun nonwovens made of nanofibers, the specimen is usually a sample strip supported by a paper frame to favour its mounting on the machine and to avoid membrane damaging.

The repeatability of a testing machine can be found by using special test specimens meticulously made to be as similar as possible. A standard specimen is prepared in a round or a square section along the gauge length, depending on the standard used. Both ends of the specimens should have sufficient length and a surface condition such that they are firmly gripped during testing. The initial gauge length Lo is standardized (in several countries) and varies with the diameter (Do) or the cross-sectional area (Ao) of the specimen as listed

The following tables gives examples of test specimen dimensions and tolerances per standard ASTM E8.

Equipment

… excerpt ends here. Continue reading the full article.

Illustrations

Tensile testing: Tensile testing on a coir composite. Specimen size is not to standard (Instron).
Tensile testing on a coir composite. Specimen size is not to standard (Instron).
Tensile testing: Tensile specimens made from an aluminum alloy. The left two specimens have a round cross-section and threaded shoulders. The right two are flat specimens designed to be used with serrated grips.
Tensile specimens made from an aluminum alloy. The left two specimens have a round cross-section and threaded shoulders. The right two are flat specimens designed to be used with serrated grips.
Tensile testing: An aluminium alloy tensile specimen, after testing. It has broken, and the surface where it broke can be inspected.
An aluminium alloy tensile specimen, after testing. It has broken, and the surface where it broke can be inspected.
Tensile testing illustration
Tensile testing illustration

Worked examples

Example 1 — a first encounter with Tensile testing

Start with the simplest possible case. Write down what Tensile testing claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In engineering, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Tensile testing before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Tensile testing ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Tensile testing

In research
Tensile testing appears in engineering research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Tensile testing in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Tensile testing is common in secondary-school and first-year university syllabi. It links to neighbouring topics Materials testing, so understanding it makes those chapters shorter.
In everyday life
Look for Tensile testing outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Tensile testing in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Tensile testing means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Tensile testing out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Tensile testing in simple terms?

Tensile testing, also known as tension testing, is a fundamental materials science and engineering test in which a sample is subjected to a controlled tension until failure. Properties that are directly measured via a tensile test are ultimate tensile strength, breaking strength, maximum elongation…

Why does Tensile testing matter?

Because it connects several engineering ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Tensile testing?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Tensile testing.

Tags

  • Materials testing

Keep exploring