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What is the breaking down of rocks called?

Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering. Once a rock has been broken down, a process called erosion transports the bits of rock and mineral away.

What chemicals break down rocks?

Chemical weathering is the process that breaks down rock through chemical changes. The most common agents of chemical weathering include water, oxygen, carbon dioxide, and living organisms.

What is the breakdown of rock into smaller pieces by physical means called?

Weathering

What is the separation of a material into two or more pieces under the action of stress?

Fracture is the separation of an object or material into two or more pieces under the action of stress. The fracture of a solid usually occurs due to the development of certain displacement discontinuity surfaces within the solid.

What is creep failure?

Creep may be defined as a time-dependent deformation at elevated temperature and constant stress. It follows, then, that a failure from such a condition is referred to as a creep failure or, occasionally, a stress rupture. The temperature at which creep begins depends on the alloy composition.

What is type of fatigue failure?

Overview of Fatigue (Material) Fatigue is a failure mechanism that involves the cracking of materials and structural components due to cyclic (or fluctuating) stress. While applied stresses may be tensile, compressive or torsional, crack initiation and propagation are due to the tensile component.

What is SN curve?

A SN-Curve (sometimes written S-N Curve) is a plot of the magnitude of an alternating stress versus the number of cycles to failure for a given material. Given a load time history and a SN-Curve, one can use Miner’s Rule to determine the accumulated damage or fatigue life of a mechanical part.

Which material does not show fatigue limit?

Aluminium

How do you prevent material fatigue?

Fatigue Reduction

  1. Use stronger, more capable materials.
  2. Reduce the margin of errors in assembly and manufacture.
  3. Avoid, soften when inevitable, stress concentrations.
  4. Keep residual stress at surface, if any, in compression.
  5. Take service environment into account.
  6. Schedule routine maintenance, firm and thorough.

What are the three stages of fatigue?

There are three stages of fatigue fracture: initiation, propagation, and final rupture.

What is the main reason for fatigue failure?

Most fatigue failures are caused by cyclic loads significantly below the loads that would result in yielding of the material. The failure occurs due to the cyclic nature of the load which causes microscopic material imperfections (flaws) to grow into a macroscopic crack (initiation phase).

Which ferrous material does not show fatigue limit?

Explanation: Cast iron being a ferrous material, shows fatigue limit. Titanium and Magnesium metals don’t show it.

Why does aluminum have no fatigue limit?

Aluminum does not have an endurance limit such as ferrous metals. Aluminum will fail if it goes though enough stress cycles. If the stress on the steel is above the endurance limit, the metal will fail and how quickly it fails depends on the magnitude of the stress. I.e. higher the stress the more quickly it fails.

What increases fatigue life?

Increases in fatigue life and strength are proportionally related to the depth of the compressive residual stresses imparted. Shot peening imparts compressive residual stresses approximately 0.005 inches (0.1 mm) deep, while laser peening can go 0.040 to 0.100 inches (1 to 2.5 mm) deep, or deeper.

What do you call the time dependent yield?

mechanical engineering questions and answers. Question 13 Time Dependent Yield Is Known As Fracture Creep None That Mentioned Eaticas.

What factor decreases toughness of material?

7. Which factor decreases toughness of material? Explanation: As the rate of loading (strain rate) increases, toughness of material decreases. With increasing temperature ductility and toughness increase.

What is the breaking stress of brittle materials?

Breaking stress is a limit state of tensile stress that leads to tensile failure in one of two manners: Ductile failure – Some yield as the first stage of failure, some hardening in the second stage and breakage after a possible “neck” formation.

Which of the following is failure of material due to cyclic stress?

Fatigue

What is creep material?

Creep is a type of metal deformation that occurs at stresses below the yield strength of a metal, generally at elevated temperatures. Creep is unique in the fact that it is a phenomena that causes materials to plastically strain even though yield stresses have not been reached.

What is example of repeated stress cycle?

What is the example of repeated stress cycle? Explanation: Axles, rotating shafts and cantilever are examples of alternating stress. Machine carrying load is an example of repeated stress cycle. In this the mean stress is positive.

Which among the following is the characteristics of brittle material?

Brittle materials are characterized by little deformation, poor capacity to resist impact and vibration of load, high compressive strength, and low tensile strength.

What is brittle material with example?

Brittle materials have a small plastic region and they begin to fail toward fracture or rupture almost immediately after being stressed beyond their elastic limit. Bone, cast iron, ceramic, and concrete are examples of brittle materials.

What kind of material is brittle?

Brittle materials include glass, ceramic, graphite, and some alloys with extremely low plasticity, in which cracks can initiate without plastic deformation and can soon evolve into brittle breakage.

What is a ductile material?

In contrast, ductility is the ability of a solid material to deform under tensile stress. Practically, a ductile material is a material that can easily be stretched into a wire when pulled as shown in the figure below.

Which is the most ductile?

platinum

Is rubber a ductile material?

RUBBER IS DUCTILE DUE TO ITS SPECIAL PROPERTY OF ELASTICITY. BUT AFTER REACHING THE FRACTURE POINT THE ELASTIC LIMIT OF RUBBER ENDS.

What does ductile mean?

capable of being drawn out

What is another word for ductile?

Some common synonyms of ductile are adaptable, malleable, plastic, pliable, and pliant.

Why is copper ductile?

Copper is a ductile metal. Copper pipes are lightweight because they can have thin walls. They don’t corrode and they can be bent to fit around corners. The pipes can be joined by soldering and they are safe in fires because they don’t burn or support combustion.

How do you use ductile in a sentence?

Ductile sentence example

  1. Sudden cooling makes the metal extremely ductile , and slow cooling makes it brittle.
  2. It is a silver-white ductile metal (of specific gravity 2.54) which melts at 8000.