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

Evaluate the shaft diameter on strength basis, The layout of a transmission...

The layout of a transmission shaft carrying two pulley C and B and supported on bearings A and D is shown in figure. Power is supplied to the shaft by means of vertical belt on pul

Draw the gas welding system, Draw the Gas welding System and label its part...

Draw the Gas welding System and label its parts. Illustrate the several types of flames used in gas welding along with temperature range.

Theory of machines, What'' is balancing and vibration in machines Need of ...

What'' is balancing and vibration in machines Need of balancing? Causes of vibration and their harmful effects and remedies?

What do you mean by compression moulding, Q. What do you mean by Compressio...

Q. What do you mean by Compression moulding? In compression molding, a material normally in power or perform shape , is loaded directly into the hot die cavity, pressure from

Safety functions - industrial safety, Safety Functions - Industrial Safety ...

Safety Functions - Industrial Safety In the statement about safety organization various functions have been mentioned. Yet, a clear description is lacking. Without much elabor

Calculate size of blank required for drawing, Calculate Size of Blank Requi...

Calculate Size of Blank Required for Drawing A flanged cup shown in Figure is to be produced by deep drawing. Calculate the size of the blank required for drawing.

Reversible and irreversible processes - thermodynamics, Reversible and irre...

Reversible and irreversible processes: Thermodynamic system which is capable of restoring the original state of it by reversing the factors responsible for occurrence of proc

Magnitude of the resultant couple, Magnitude of the resultant couple: ...

Magnitude of the resultant couple: For non-parallel forces also the location of the line of action of resultant may be determined by utilizing R × d = ∑ M o . The magnitu

Schedule evaluation, Schedule Evaluation Each continuations of a partia...

Schedule Evaluation Each continuations of a partial schedule that are produced in step 1 are ranked as per to their respective cost function. This cost function might be dissim

Binomial distribution, Binomial distribution: Let X follow a binomial ...

Binomial distribution: Let X follow a binomial distribution with parameters n = 4 and p = 0.5. Tabulate P ( ¦X - μ¦ ≥ k ) and σ 2 /k 2 for k = 1,2,3,4,5 and verify that Cheby

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