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

Process selection in making a simple part, Process Selection in Making a Si...

Process Selection in Making a Simple Part You should first determine the part's function, the types of load and environment to which it would be subjected, the dimensional to

Thermodynamics, can u please explain me d concept of 2nd law of thermodynam...

can u please explain me d concept of 2nd law of thermodynamics. I am not so sure about it ??

Parallel foreces, what do you understand by two like and unlike parallel fo...

what do you understand by two like and unlike parallel forces?

Determine thermal contact resistance, Derive the mathematical Heat Conducti...

Derive the mathematical Heat Conduction equation through a composite wall. Determine Thermal contact Resistance ?

Thermodaynamic, Ask question #MiThe steam that leaves the super-heater is e...

Ask question #MiThe steam that leaves the super-heater is expanded from 130bar at 535°C to 25.2bar at 310°C in a high pressure turbine. The steam from the exit of the HP turbine is

Hydrostatic pressure, can a swimming pool that is full be cracked or lifted...

can a swimming pool that is full be cracked or lifted by hydrostatic pressure?

Frictional force acting on the ladder, Frictional force acting on the ladde...

Frictional force acting on the ladder: A uniform ladder having length 13m and weighing 250N is placed against smooth vertical wall with its lower end 5m from wall. The coeffi

Determine the point of contraflexure - overhanging beam, Determine the poin...

Determine the point of contraflexure: Draw the shear force & bending moment diagram for 10 m span overhanging beam along overhanging part of 4 m subjected to a system of loads

Laminar flow, Consider fully developed laminar flow with constant propertie...

Consider fully developed laminar flow with constant properties in a circular tube. Let there be heat transfered  to or from  the fluid at a constant rate per unit of tube length.Ad

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