Macroscopic fracture mechanics sealer shear fracture process analysis

Source:   Date:2014-10-28 15:46:34   Views:

Sealing and cutting performance of the shearing process of the fracture is generated on a macroscopic crack, extended, until the final fracture splitting, the fracture of the material due to the presence of cracks results in further expansion, and crack under the action of the force is in a static equilibrium or extension, all have a direct relationship with the crack tip stress field attachment. So in fracture mechanics scholars proposed a "fracture stress intensity factor" concept, in order to balance the occurrence of a given crack development. Stress intensity factor was first used by Irwin through a new parametric study of the stress field near the crack tip proposed and established a fracture criterion, at present, the criterion on the project has been widely used.
Type crack stress intensity factor: As already mentioned u type refers to a material that is pure crack sealing and cutting machine shearing stress and the formation of the slide-open cracks, sealing and cutting machine shearing action of the clamping force when the shear blade attachment material is pure shear stress state. Now when we come to discuss the subject of pure sealer shear stress of the material stress intensity factor.
Component, in which several (9) is a function of the polar angle e, called the angular distribution function. K. Characterization of the region near the crack tip stress field strength level, referred to as the stress intensity factor or K factor. The value of K is contained in the nature and parameters, the crack, the crack geometry elastomers and other factors relating to the slide-open crack crack is:
Where a- crack length;
P- sealer shear force;
d- package diameter.