Thermoplastics, having strong polar or hydrogen bonding groups, are potenti
al candidates for thin film bonding. In this investigation, a thermoplastic
polymer poly(ether ketone ether ketone ketone) (PEKEKK) is used as an adhe
sive to bond the titanium alloy (Ti-6Al-4V). The titanium alloy is silicon-
sputtered to improve the bond strength to PEKEKK. The bond strengths of but
t-joined specimens prepared using silicon-sputtered, silane-coated, sodium
hydroxide-anodized round bars of titanium alloy as adherends are determined
and compared with that of untreated titanium alloy round bars. Of the vari
ous thicknesses of silicon layers studied, layers that are 200 Angstrom thi
ck proved to have a more durable bond, as demonstrated by soak test results
in Ringer's solution. It is observed that silicon sputtering enhances the
bond strength of titanium alloy/PEKEKK butt joints and provides a more resi
stant interface to intruding water. The combination of anodization followed
by silicon sputtering further improves the durability of the bond. It is c
onfirmed by XPS analysis that fracture does not take place between the sili
con and the titanium substrate. Wetting studies by contact angle method usi
ng water as test liquid, indicate significantly better wetting after silico
n sputtering for Ti-6AL-4V adherends. (C) 1998 Elsevier Science Ltd. All ri
ghts reserved.