2.18 ( Charpy impact Test )

ASTM ( Simple beam ) 2-20

2-20

40

30 2- 2.5

2.18 2.18.1 Impact test ( ,2546 : 81-83)

2-21 (Pendulum) ( Specimen) ( Dial indicator ) 2.18.2 ( Impact Speed ) = FG ( ) . h1 = 2

v.m 2 ( )22 sccm.kg v =

mh).(FG2 1

FG ( ) = g.m

2sec

m.kg N

v = m

h.g.m2 1

v = 1h.g.2 ( )secm (2.3) 2.8.3 ( Impact work ) W =

21 potpotEE

= 21 h.FGh.FG h1 = h2 = FG ( h1 h2 ) h1 = h2 h2 < h1 h2 W = )hh(g.m 21 ( N.m) J () (2.4) 2.18.4 ( Impact Strength ak ) A 0 = b. ( h t ) ( cm2 ) ak =

= 0AW ( )2cm/m.N

( )2cm/J ak = )t -h b(

)h-h (g .m 21 ( )2cm/J (2.5) 1 kpm = 9 . 80665 J 9.81 J 1 J = 0.101927 kpm 0.102 kp m = ( kg ) g = ( m/sec 2) h1 = ( m ) FG ( ) = ( N ) b = ( mm ) h = ( mm ) t = ( mm )

2.19 (Calibration and Verification) 3 2.19.1 ( Weights alone ) 2.19.2 ( Weights and levens ) 2.19.3 ( Proving ring ) 2-22

2-22

0.001 ..

Upper bass

Spring steel reed

Micrometer dial

Lower bass

1) 2) 3) 4) 5) 2.19

, ( 2546)

300 10 x 10 x 55