Abstract:
Niello bars contain Lead which prohibits by laws and danger to environment. This research was to study the effects of temperatures which a black amalgam of lead-free niello bar alloys was filled in carved grooves of 95wt%Ag-5wt%Cu and 99.99wt%Ag substrates at 400°C, 500°C, 600°C and 700°C. Three compositions of lead-free niello bar alloys were selected in this research. The characterizations of microstructure, interface layers, and porosities of lead-free niello bar alloys after applying were reported. The results showed that all three compositions contain six compounds of CuAgS, Ag, Cu2S, Sn2S3, SnS and Cu4SnS4. After applying lead-free niello bar alloys on the substrates, it showed that composition #2 on the 95wt%Ag-5wt%Cu substrates was matched to the best condition of temperature at 600°C giving lowest porosities. © (2013) Trans Tech Publications, Switzerland.