Issue 14

V.

Di Cocco et alii,

Frattura ed Inte

grità Strutturale

, 14 (2010) 52

-63; DOI: 10.322

1/IGF-ESIS.14.06

In di

fluence p galva

of dipp

ing tim

e on c with S

racking n and T

during i conte

bendin

g of ho

t

nized c

oatings

nts

V. Un v.d L. Un

Di Cocco iversità di Ca icocco@unicas Zortea iversità di Ro STRACT . In tection tech vanizing is rs: some ch idizing prop . … Pb!). this work, t s investigate ted ipersan ded specim cromechani YWORDS . H

ssino, Di.M.S .it

.A.T., via G

. Di Biasio, 4

3 03043, Ca

ssino (FR), I

taly

ma “Sapienza

”, Dip.I.C.M

.A., Via Eu

dossiana 18,

Roma, Italy

the last ye niques, int a classical p emical elem erties, some he influence d consideri delin steel ens were sms were id ot dip galva of hot dip g , it is still one e environmen ades, new nted to use in gs growth is ture [5]. Ma different ch lic layers are tents (Fig. 1) nd by a very t%, with H a radial orie ain a  phas r and by a ve N

ars, the att roducing in rocess aime ents are ad times repla of dipping ng differen specimens observed entified as lo nizing; Inte alvanizing h of most im ts [1]. investigation high plastic a diffusion d ny intermeta emical comp usually ob . The inner l low thicknes CP unit cell nted morpho e with not-o ry low Fe co

ention to en novative wa d to genera ded in the ced by Sn) b time and co t Sn and Ti were invest by means ngitudinal a rmetallic ph ave remaine portant proc s on bath c deformation riving pheno llic phases c ositions, mor served in cla ayer, namely s, often negl and a brittl logy, due to riented morp ntent.

vironmenta y oriented te coatings bath with ut sometim atings chem contents. M igated by m of a LO nd radial cr ases; Dama d unchanged essing techni ompositions s [1-4] or in r menon, whe ould be obta phologies an ssical Zn, Z  phase (gen igible [3].  p e behaviour. growth mech hology [6].

l topics led to optimize on iron-base different aim es these ele ical compo ain damag eans of be M (Light acks. ge analysis. since this c que to prote were perfo einforced co re Zn and Fe ined depend d mechanical n-Pb and Z erally BCC), hase is chara  phase, lo anisms. Dep The outer la

a new app different c d surfaces, s (e.g., Pb ments are d sitions on d ing microm nding tests Optical M

roach solut oating prop used uncha is really im angerous fo amaging mi echanisms . Longitudi icroscope):

ion in class erties. Hot nged since portant for r human he cromechani in hot dip z nal sections main dam

ical dip 200 its alth sms inc of age

A B pro gal yea flu (e.g In wa coa ben mi

K E

I N

TRODUCTIO

P

rinciples Actually corrosiv

oating came ct carbon ste rmed to ge mponents. atoms are c ing on Zn c behaviour. n-Sn coating is characteriz cterized by a cated betwee ending on th yer (η phase

into use ove els against co nerate coatin haracterized ontents [3]: s: they are ed by the hi Fe content n  and the e hot dipping , HCP) is ch

r 200 years rrosion in m gs “mechan by interdiffu these phases characterized ghest Fe con ranging betw outer phase conditions, aracterized b

ago. any ical sion are by tent een , is it is y a

In beh Zn at cha Fou dif (17 7.0 cha pos duc

the last dec aviour” orie -based coatin high tempera racterized by r intermetal ferent Fe con -28 wt %), a and 11.5 w racterized by sible to obt tile behaviou

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