Calculate the critical crack length, Mechanical Engineering

Assignment Help:

Calculate the critical crack length:

A wide plate of mild steel is subjected to uniform tensile load causing a stress of 100 MPa. Calculate the critical crack length in the centre of plate which when reached will cause the plate to fracture, if fracture toughness of mild steel is 1340 N / mm2

Solution

The crack will become unstable in the centre of the plate, i.e. the fracture will occur when the crack has attained a critical length (say ac) under given stress ? which remains constant. At this moment KI → KIC.

KI for a large plate with central crack of length 2a is by Eq.

1433_Calculate the critical crack length.png

and hence

211_Calculate the critical crack length1.png

or        

629_Calculate the critical crack length2.png

∴          2ac = 114.3 mm

[This example explains how the knowledge of fracture toughness of material and KI of a crack can be used to calculate the length of a crack which must not be permitted to exist. If the cause of crack extension may not be controlled, the only thing left to designer is to calculate critical length in advance. Then the crack length would have to be monitored throughout the life of the structure and as soon as it approaches the critical value, the structure should be discarded to avoid sudden fracture or other measures be taken by which either KI is reduced to KIC is improved.]


Related Discussions:- Calculate the critical crack length

What are the causes of high fuel consumption, (a) What are the causes of hi...

(a) What are the causes of high fuel consumption? (b) How can the problem of "motorcycle pulls to one side" be corrected? (c) How can engine overheating problem be solved?

Fluid mechanics and machinery diploma .., Prove that the force exerted by a...

Prove that the force exerted by a jet of water on a semicircular plate in the direction of the jet when the jet strikes at the centre of the semicircular plate is two times the for

Mounting systems for the welding head-carriage mounted type, Mounting Syst...

Mounting Systems For The  Welding Head-Carriage mounted type In this set up, the welding head is mounted on a movable carriage. The carriage is mounted on rails and powered by a

Shielding gas-argon-advantages of argon, Argon Argon is approximatel...

Argon Argon is approximately one and one third times as heavy as air and ten times heavier than helium. Argon, after leaving the torch nozzle, forms a blanket over the weld

Rankine cycle with respect to p-v, Rankine cycle with respect to P-V, T dia...

Rankine cycle with respect to P-V, T diagrams: The steam having high pressure is expanded to a low pressure within a reciprocating engine or a turbine. If expansion is idea

Backup purge, Backup Purge Backup purge gas can also be used to prot...

Backup Purge Backup purge gas can also be used to protect the under side of the weld and its adjacent base metal surfaces from oxidation on the time of welding . Uniformity

Metallurgy, Write a literature review on the manufacture and application of...

Write a literature review on the manufacture and application of metallurgical cokes in Nigeria.

Wet saturated steam - thermodynamics, Wet saturated steam -  thermodynamic...

Wet saturated steam -  thermodynamics: we t saturated steam Wet steam is a 2-phase mixture comprising of boiling water particles and dry steam in equilibrium state. Its for

Plate clutch pressure height-clutch slipping, Plate clutch pressure height ...

Plate clutch pressure height : Check plate clutch pressure leg height by placing the plate clutch pressure on the surface plate. Plate clutch pressure should not tilt on the surfa

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd