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

Determine the apparent range of the target - radar system, Consider radar w...

Consider radar with a PRF of 5 kHz. What is the maximum unambiguous range R ua of this radar, in km?  If a target is located at a range of 50 miles, how many pulses will the r

What is boiler feedwater, Q. What is Boiler feedwater? The boiler feedw...

Q. What is Boiler feedwater? The boiler feedwater will be a mixture of desalinated water, treated make-up water and returned condensate, deaerated and heated, supplied by other

Sketch merchants force diagram, Merchants force diagram. State the assumpti...

Merchants force diagram. State the assumptions made in development of such diagram.

Determine the maximum permissible eccentricity of the load, Determine the m...

Determine the maximum permissible eccentricity of the load: A small hollow cylindrical column carries a compressive force of 400 kN. The external diameter of the column is 200

Illustrate working of double acting steam engine, Illustrate working of dou...

Illustrate working of double acting steam engine. What is its diagram factor and thermal efficiency?

What are the basic different air-fuel mixture, Describe carburetion. What a...

Describe carburetion. What are the basic different air-fuel mixture on which an engine can be operated ? Write a short note on sterling cycle. In an engine working on inlet pres

Gear Transmission Systems, Develop a computer program for the “Gear Transmi...

Develop a computer program for the “Gear Transmission Systems” with consideration that each gear designer will have a different view as to what the most important design factors ar

Calculate diameter of shaft in maximum direct stress, Calculate diameter of...

Calculate diameter of shaft in maximum direct stress: A shaft is designed for transmitting 100 kW power at 150 rotation per minute. Shaft is supported in bearings 3 m apart a

Compute the total drag force on the plate , A uniform air stream with veloc...

A uniform air stream with velocity U = 10m/s flows over a flat plate of length 10 meters in the first meter the boundary layer is laminar but beyond this point boundary layer is fu

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