Calculate the critical crack length, Mechanical Engineering

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.]

Posted Date: 1/22/2013 2:01:07 AM | Location : United States







Related Discussions:- Calculate the critical crack length, Assignment Help, Ask Question on Calculate the critical crack length, Get Answer, Expert's Help, Calculate the critical crack length Discussions

Write discussion on Calculate the critical crack length
Your posts are moderated
Related Questions
Upward Compatibilityof IGES Upward Compatibility : The need for generations of processors to parse files compliant with earlier versions of IGES thwarted the breadth and rate o

Explain Side Cutting Edge Angle It is angle between the side cutting edge and the longitudinal axis of the tool. It avoids formation of build up edge, controls the direction of

Expression for the normal and tangential stresses: By sing Mohr's circle, derive expression for the normal and tangential stresses on a diagonal plane of material subjected t

Determine least value of work: Q . Determine least value of W as shown in the figure given below to keep the system of connected bodies in equilibrium µ for surface of c

Ask question # how to derive a expression for the centifugal tension in belt driver

Inspection of Electrical Equipment STEPS All electrical equipment are checked for proper functioning. The starting and lighting of the motorcycle should be prope

Q. What do you mean by Risers and Downcomers? Risers and downcomers shall be staggered along the shell of the WHB and steam drum for uniform water/steam circulation in the syst

Find out the quality: ABC industries manufacture X-band radar scanners utilized to detect speed traps. The printed circuit boards in the scanners are bough from an outside ven

Define Cam Operated Clamp 1. The cams operated clamp find wide application and are fast and positive in action. 2. These should not be used where vibrations are present or w

EXPALIN PREPARATION OF LYOPHILIC AND LYPHOBIC SOLS