7.2 Impact Test on 10CrNi3MoV21A Armor Steel/SiC Ceramic/UHPCC …
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0.00
0.03
0.06
0.09
0.12
0.15
0.18
0
200
400
600
800
1000
1200
1140s
-1
1152s
-1
True stress (MPa)
True strain
0.00
0.05
0.10
0.15
0.20
0.25
0
200
400
600
800
1000
1200
True strain
1635s
-1
1660s
-1
1700s
-1
True stress (MPa)
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0
200
400
600
800
1000
1200
1930s
-1
1980s
-1
1964s
-1
True stress (MPa)
True strain
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0
200
400
600
800
1000
1200
2279s
-1
2300s
-1
2285s
-1
True stress (MPa)
True strain
(a)
(b)
(c)
(d)
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45
0
200
400
600
800
1000
1200
2820s
-1
2762s
-1
2776s
-1
2749s
-1
2756s
-1
2720s
-1
True stress (MPa)
True strain
(e)
Fig. 7.20 Dynamic compressive stress–strain curves of armor steel under different incident air
pressures a 0.1 MPa b 0.2 MPa c 0.3 MPa d 0.4 MPa e 0.5 MPa
ln(σ − A) = ln B + n ln ε
(7.5)
The value of constant A can be determined as 665 MPa from the quasi-static tension
tests. Then, based on the data within the plastic stage of the quasi-static tensile test,
and substituting the value of A into Eq. (7.5), the values of B = 950 MPa and n =
0.83 are further obtained by fitting the relationship between ln(σ-A) and lnε. The