الفهرس 
Introduction
Study the effects of adding cadmium on structure and some physical properties of tin-silver based lead free solder alloy and some physical properties of tin-silver based lead free solder alloyOnly 14 pages are availabe for public view
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Abstract
The objective of this work was to improve soldering and physical properties of eutectic tin- silver lead free solder alloy by adding different alloying elements such as cadmium, bismuth and bismuth-zinc. Also to produce new lead free solder alloy friendly environmental for electronic applications.
To verify this aim we do the following:- 1. 1-Melt spinning technique was used to prepare three groups, first group is Sn96.5-x Ag3.5Cdx (x=0, 2.5, 3.5, 4.5, 6.5, 8.5, 10), second group is Sn91.5-x Ag3.5Bix (x=5, 10, 15, 20) and third group is Sn76 Ag2Zn2Bi20 and Sn60 Ag3Zn2Bi35. 2. 2-Studying and analysing structure, electrical resistivity, elastic modulus, internal friction, melting point and contact angle of these alloys using different experimental techniques. from this studying it’s obvious that:
X-ray diffraction patterns and its analysis show that, Sn96.5-xAg3.5Cdx (x= 0, 2.5, 4.5, 6.5, 8.5 wt. %) and Sn88Ag2Cd10 melt spun alloys have lines corresponding to sharp lines of body-cantered tetragonal Sn phase and hexagonal Ag3Sn\ intermetallic compounds.
Adding Cd content to Sn- Ag melt spun alloy caused a significant change in its contact angle, wettability. The Sn88Ag2Cd10 melt spun alloy has lower contact angle.
Adding Cd content to Sn- Ag melt spun alloy increased its electrical resistivity and decreased its elastic modulus and internal friction.
X-ray diffraction patterns and its analysis of Sn96.5-x Ag3.5Bix (x=5, 10, 15, 20) melt spun alloys have lines corresponding to sharp lines of body-centered tetragonal Sn phase, hexagonal Bi phase and Ag-Sn intermetallic compounds.
Adding bismuth content to Sn- Ag melt spun alloy caused a significant effect in contact angle. The Sn76.5Ag3.5Bi20 melt spun alloy has lower contact angle.
Adding Bi content to Sn- Ag melt spun alloy deceased its melting point. The Sn76.5Ag3.5Bi20 melt spun alloy has lowest melting point, 193.75°C.
Adding Bi content to Sn- Ag melt spun alloy increased its electrical resistivity and decreased its elastic modulus and internal friction.
Adding Bi and Zn content to Sn- Ag melt spun alloy deceased its melting point. The Sn60Ag3Zn2Bi35melt spun alloy has lowest melting point, 139.34, and smaller than the melting point of Sn-Pb solder alloy
Adding Bi and Zn content to Sn- Ag melt spun alloy increased its electrical resistivity and decreased its elastic modulus, melting point and internal friction.
from our work it’s concluded that:-
We can improve physical and soldering properties of SnAg3.5 lead free solder alloy by adding different alloying elements such as bismuth or bismuth\zinc and reducing tin content. Also we can produce new lead free solder alloys, Sn-Ag-Bi, Sn-Ag-Zn-Bi, friendly environmental.
Keywords:Lead free solder alloys, tin- silver eutectic alloy, electrical properties, mechanical properties, soldering properties, thermal properties