Determine the number of cycles - crack propagation, Mechanical Engineering

Determine the number of cycles - crack propagation:

The plate of above Example  contained a crack of 50 mm length in the centre before it was subjected to cyclic stress. Determine the number of cycles the plate would undergo when final fracture occurs.smax = 100 MPa, smin = 30 MPa and law of crack propagation for material of plate is

         da  / dN  = 10-8 (Δ K I )2.25 mm/cycle

Solution

The half crack length at which fracture will occur was calculated as ac = 57.17 mm.

924_Determine the number of cycles.png

553_Determine the number of cycles1.png

∴          Δ K I =  K I max  - K I min

1315_Determine the number of cycles2.png

Using this value of Δ KI in law of fatigue crack propagation, i.e. the plate is likely to fracture under smax = 100 MPa,smin = 30 MPa if plate contains a central crack of 50 mm length, after 1048 cycles.

1764_Determine the number of cycles3.png

da / dN  = 10-8 (124)2.25 (a)2.25 / 2

= 0.51´10- 3 (a)1.125

Posted Date: 1/22/2013 2:06:43 AM | Location : United States







Related Discussions:- Determine the number of cycles - crack propagation, Assignment Help, Ask Question on Determine the number of cycles - crack propagation, Get Answer, Expert's Help, Determine the number of cycles - crack propagation Discussions

Write discussion on Determine the number of cycles - crack propagation
Your posts are moderated
Related Questions
Volume fraction of fibres: The epoxy material is prepared to be stressed to its full strength. What must be volume fraction of fibres? Solution Here σ′ = 1200 MPa,

Q2 A 3kW electric water heater is a cylindrical element having outside diameter 10mm. The heat transfer between the heater and the surrounding water is 980W/m2K. Determine the leng

CAD-CAM Data Exchange: The interface SET transferred information on wire-frames, surfaces, B-representation and FEM models as well as technical drawings and scientific data. I

The specifications for use on a project will be as defined in the Project Execution plan. The Specification requirements will be clarified in the Engineering Estimate or at the Pr

(Buoyancy; force & moment balance) A partially submerged, homogeneous timber is 0.15m by 0.35m in cross-section. What is the specific weight of the timber and the tension in the r

What is the difference between counter flow and parallel flow Heat exchange. Classify Heat exchange on the basis of constructional features and design.

Four diametrically opposed in vessels up to pilot scale. More applied in production vessels. Thickness typically 0.1 - 0.05 tank diameter. Baffle height is dependent on the gas

A Boot Strap Cooling system of 10 TR capacity is used in an aeroplane. The ambient air pressure and temperature are 0.85 and 20 0 C bar respectively. The pressure of air increases

the cable AB which connects two structures carries a tension of 400N. express the force F which acts on point A as a vector in terms of the unit vector.determine the project of F

Tyre: Different bikes respond differently to different tyres, so it is impossible to make a generic recommendation. It mainly consists of outer cover and inside tube. The tyre tub