Issue 54

A. Moslemi Petrudi et alii, Frattura ed Integrità Strutturale, 54 (2020) 226-248; DOI: 10.3221/IGF-ESIS.54.17

The rate of change of the work done by the beams on the joint surface of the ceramic backing layer as shown in Fig. (9) is:

2 b c dT f R w dt  

(17)

Figure 9: Ceramic cone and force applied to the backing layer [10].

where W is the surface velocity of the ceramic backing joint. Therefore, the kinetic energy conversion rate for the active region of the backing layer is: ) 18 ( 2 k b b dE dw R h w dt dt   

Given the energy balance:

p k dE dE dT dt dt dt  

) 19 (

dw

2 3

) 20 (

 



2

2 R h

b c f R h Y h   b b

   



b

b b

dt

 From the above equation, we can calculate W. At very high impact velocities, the conical ceramics may be completely eroded, and therefore the projectile may come in contact with the back material. In this case, the actual behavior represents the speed difference between the projectile and the metallic material. Based on the Tate equations, the projectile motion equation can be modeled as follows:

1 2





2



b   p

v w 

Y

dv dt

) 21 (

b

 

L

The equation of motion of the back material is given by the following Eqn. (17):

2

D

1 4

2 3

 

 

eq



b b h Y h 

   



Y

) 22 (

b

b

dw dt

4



M

b

b M is the effective mass of the area and is equal to:

where

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