سال انتشار: ۱۳۸۷

محل انتشار: دومین کنگره بین المللی علوم و فناوری نانو

تعداد صفحات: ۲

نویسنده(ها):

F Soleimangoli – Material Engineering Faculty.Sahand
N Parvini-Ahmadi –
R Azari-Khosroshahi – Material Engineering Faculty.Sahand University,Tabriz.Iran

چکیده:

Electroless Ni-based coatings are special interest due to their properties such as good corrosion and wear resistance, deposited uniformity, electrical and thermal conductivity. These are widely used in chemical, aerospace, automobile and textile industries. The quality of coatings is dependent upon the microstructure and composition of the deposits. Electroless process for nickel coatings produces deposits having microcrystalline, amorphous or fully crystalline nature over a wide range of compositions [ ]. In general, Electroless Nickel deposits are classified into three categories: low ( wt. %), medium ( wt. %) and high ( wt. % and above) phosphorus deposits. Studies have shown that as-coated low-phosphorus deposits are either crystalline or consist of microcrystalline nickel. As-coated medium-phosphorus deposits are reported to be either fully amorphous or mixtures of microcrystalline nickel and amorphous phases. Studies on high-phosphorus as-coated deposits have demonstrated that the deposits could be fully amorphous, mixtures of microcrystalline nickel and amorphous. [ ]The crystallite size of the coatings determines the quality of coatings. The crystallite size may be influencing the Peak broadening in the coatings [ ]. In this paper, the effect of pH, sodium hypophosphite, copper sulphate and sodium sitrate concentration on microstructure of Ni-Cu-P coatings were investigated