science

Partial dislocation

Partial dislocation is a science 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 Partial dislocation rather than just read about it. In short: In materials science, a partial dislocation is a decomposed form of dislocation that occurs within a crystalline material. An extended dislocation is a dislocation that has dissociated into a pair of partial dislocations.

Key takeaways

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

Reference excerpt

In materials science, a partial dislocation is a decomposed form of dislocation that occurs within a crystalline material. An extended dislocation is a dislocation that has dissociated into a pair of partial dislocations. The vector sum of the Burgers vectors of the partial dislocations is the Burgers vector of the extended dislocation.

Reaction favorability A dislocation will decompose into partial dislocations if the energy state of the sum of the partials is less than the energy state of the original dislocation. This is summarized by Frank's Energy Criterion:

| b 1 | 2 > | b 2 | 2 + | b 3 | 2 (favorable, will decompose) | b 1 | 2 < | b 2 | 2 + | b 3 | 2 (not favorable, will not decompose) | b 1 | 2 = | b 2 | 2 + | b 3 | 2 (will remain in original state) {\displaystyle {\begin{aligned}|{\boldsymbol {b_{1}}}|^{2}>&|{\boldsymbol {b_{2}}}|^{2}+|{\boldsymbol {b_{3}}}|^{2}{\text{ (favorable, will decompose)}}\\|{\boldsymbol {b_{1}}}|^{2}<&|{\boldsymbol {b_{2}}}|^{2}+|{\boldsymbol {b_{3}}}|^{2}{\text{ (not favorable, will not decompose)}}\\|{\boldsymbol {b_{1}}}|^{2}=&|{\boldsymbol {b_{2}}}|^{2}+|{\boldsymbol {b_{3}}}|^{2}{\text{ (will remain in original state)}}\end{aligned}}}

Shockley partial dislocations Shockley partial dislocations generally refer to a pair of dislocations which can lead to the presence of stacking faults. This pair of partial dislocations can enable dislocation motion by allowing an alternate path for atomic motion.

b 1 → b 2 + b 3 {\displaystyle {\begin{aligned}{\boldsymbol {b_{1}}}\rightarrow {\boldsymbol {b_{2}}}+{\boldsymbol {b_{3}}}\end{aligned}}}

In FCC systems, an example of Shockley decomposition is:

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with Partial dislocation

Start with the simplest possible case. Write down what Partial dislocation claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, 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 Partial dislocation 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 Partial dislocation 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 Partial dislocation

In research: Partial dislocation appears in science 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 Partial dislocation 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: Partial dislocation is common in secondary-school and first-year university syllabi. It links to neighbouring topics Crystallographic defects, so understanding it makes those chapters shorter.
In everyday life: Look for Partial dislocation 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.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Partial dislocation” →

Affiliate

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

How to study Partial dislocation in 20 minutes

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

Frequently asked questions

What is Partial dislocation in simple terms?

Why does Partial dislocation matter?

Because it connects several science 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 Partial dislocation?

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 Partial dislocation.