Issue 14

D.

Firrao et alii, Fr

attura ed Integri

tà Strutturale, 1

4 (2010) 81-92

; DOI: 10.3221/I

GF-ESIS.14.09

h b 1 ere b 1 is the B other relation (1/  3)( h b = a o  2/ ere b is the B thermore, R ation (4) and s on monocr ally, a perfec tting data of ight line pas ulated from ues of  c,twin , four above m .31, whereas more recent ulations by I ] into the equ el containing the screws o orted in Tab making simi owing Tab. 3 = a o /  6

wit wh An

urgers vecto is derived b 1/3 + k·  c,twi 2 urgers vecto emy and Pin the other o ystals and po t linear corr every FCC m ses through unknown  sf derived for entioned m a o was taken calculations nakatsu [20] ation propo about 3.5% f the Triple . 2. lar calculatio can be furth n

r of the Shoc y Remy and P

kley semi-dis ineau [17], u G =  sf /G·b dislocation. pared two c n the ordinat th the second e traced put ich the perta nd its angul inless steel h isted in Tab. . ed by takin rating more s and Thom mJ/m 2 . Not ISI 303) th Suzuki and 8].

location and sing a formu

a o is the latti la proposed

ce constant. by Venables

[5]:

/G)  c,twin

/

(4)

wit wh Fur equ test Fin plo stra calc Val the = 0 If calc [21 ste of rep By foll

r of a perfect eau [17] com ne plotting o licrystals. Wi elation can b etal for wh the origin a data [3, 18]. austenitic sta ethods, are l as 0.359 nm are perform , and incorpo sed by Rhode Cu [18]: 31.3 Indicator (A ns basing on er derived [1

g  c,twin /G t xperimental ossible value gram  sf in o  c,twin values t is 0.452. T three increa tained as 73,6 nt both dat ales et al. res ore precise Cu, which w to only 21 r Remy and

o  sf /G·b: o data, obtaine s of  c,twin ca rdinate and are available hen, unknow value 60 MPa assu a by Choi e ults on the e value of  sf c as in a small mJ/m 2 , whic Pineau [17], a) y and Pineau erimental dat 103 sing  sf

ne with  c,tw d by several n be comput the twin-  crs in the literat n  c,twin valu s in the 10-2 ming E=193 Jin [19], w ffect of Cu i an be obtain quantity in t h confirms or Firrao et

urves relatin e axis  c,twin e plot other p ting on a dia ining  sf and ar coefficien ypothesizing 2; G was ob g into accou recent Gonz pson [22], a m considering e value falls Barrett [6], o emy and Pine Eq. 4 81 70 55 for twinning ( energy  sf der

in derived by researchers w ed. s in abscissa ure. The deri es can be ea 0 mJ/m 2 and ,000 MPa an ho started f n stainless st ed for a stain he stainless s the assumpti al. [3] works

the ith

and ved sily by d  rom eels less teel ons the

Alloy

Hypothesiz  sf (mJ/m 2 )

ed

 c,twin

(MP Rem exp

Suzuk Barrett

y and , Eq. 3

R

au,

Experi co

mental linear rrelation

a

Stainless Steel (AISI 304)

20 15 10 Table 2 : C

6 5 3 ritical resolve as a function o

8 1 4

44 33 22

81 66

 c,twin ) for aust ived by differe  c,t nd Remy Pin

d shear stress f staking fault

enitic stainless nt methods [3

steels and ].

(MPa)

win

thesized  sf J/m 2 ) 80 70 60 45 40 35 20 25 30 hear stress for from γ sf using

Hypo

M

etal or alloy

Suzuky a Barrett

and

Li

near correlati 177 155 133 100 88 77 44 55 66 ys calculated

on

(m

eau

272 238 204 135 120 105 67 84 101

17 16 15

5 3 0

Copper

9 9 8

8 2 6

Au-Ag alloy

C

u containing tenitic stainle steel Table 3 : Cri

10 11 13

4 8 1 metals or allo .

aus

ss

twinning (  c,t formulas by v

tical resolved s

win ) for various arious authors

88