الفهرس 
Introduction
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Abstract
In this work, we present a new pb-free quaternary solder bearing alloy based on the Sn-Sb- Cu-Zn system, with substantially improved mechanical properties over those of the bearing Sn- Sb alloy. To get this aim we do that:- Rapid solidification is achieved by melting spinning, melt spinning technique was used to Produce ribbons from tin- antimony- copper based alloy with adding 2 wt% of different alloying elements (lead or silver or cadmium or selenium or zinc) then study and analyze structure, electrical resistivity, elastic modulus, Vickers hardness number, internal friction and creep behavior of these alloys using different experimental techniques (x-ray diffraction to study structure, double bridge method to measure electrical resistivity, dynamic resonance technique to measure elastic modulus, internal friction and Vickers microhardness tester, FM-7, to measure Vickers hardness number) . from this studying it’s obvious that:- 1-The Sn90-2x–Sb10Cu2X2(X=Pb, Ag, Cd, Se and Zn) alloys consists of body-centered tetragonal tin phase (ß-Sn) and SnSb & Ag3Sn intermetallic compounds as precipitates within ß- Sn matrix. 2-Values of electrical resistivity, elastic modulus, internal friction and Vickers hardness number of Sn90-2x–Sb10Cu2X2(X=Pb, Ag, Cd, Se or Zn) alloys are varied as seen in table (1) related to alloy composition. 3-The stress exponent values of Sn90-2x–Sb10Cu2X2(X=Pb, Ag, Cd, Se or Zn) are in the range of 3.39 to 5.12 depending on the composition of used alloy and that is agrees with the other pervious results. 4-The Sn90-2x–Sb10Cu2Znx(X=0.5, 1, 1.5, 2 and 2.5 wt %) alloys consists of ß-Sn, SnSb & Cu3Sn intermetallic compounds and dissolved Zn atoms imbedded in ß-Sn matrix. 5-Values of electrical resistivity, elastic modulus, internal friction and Vickers hardness number of Sn90-2x–Sb10Cu2Znx(X=0.5, 1, 1.5, 2 and 2.5 wt %) alloys are varied as seen in table (2) related to alloy composition. from our work it’s concluded that: 1-All measured physical properties, (such as electrical resistivity, elastic modulus, and internal friction and Vickers hardness number) are affected by changing on ß-Sn matrix microstructural such as SnSb & Ag3Sn & Cu3Sn intermetallic compounds, dissolved (Pb, Cd, Ag, Se and Zn) atoms imbedded in it and phases crystal size. 2-The Sn86Sb10Cu2Zn2 quaternary alloy has better properties such as high values of stress exponent (wear resistance), Vickers hardness number and adequate values of elastic modulus and internal friction with low value of temperature coefficient of resistivity for industrial applications and eco-friendly. 3- The promising mechanical properties of the quaternary Sn86–Sb10Cu2Zn2 alloy are presently being investigated in greater detail with regard to fatigue, creep behavior and results will be reported in future publications. . Alloy ρ(μΩ.cm) T.C.R (K-1) E (GPa) Q-1 VHN Stress exponent (n) Sn86Sb10Cu2Pb2 38.23±4.92 0.05 30.40±8.49 0.049 17.82±0.57 3.349 Sn86Sb10Cu2Zn2 44.8±2.30 0.006 24.46±4.47 0.082 34.32±0.17 5.046 Sn86Sb10Cu2Ag2 49.6±1.07 0.002 28.80±3.50 0.097 9.88±0.80 4.967 Sn86Sb10Cu2Se2 55.17±6.39 0.004 27.39±3.67 0.060 23.36±1.48 4.973 Sn86Sb10Cu2Cd2 59.64±3.09 0.001 18.04±3.96 0.054 16.00±0.84 4.799 Table (1):- Physical properties of Sn90-2x–Sb10Cu2X2 (X=Pb, Ag, Cd, Se or Zn) alloys. Alloy ρ(μΩ.cm) T.C.R (K-1) E (GPa) Q-1 VHN Sn87.5Sb10Cu2Zn0.5 54.80±2.3 0.100 16.70±1.46 0.050±0.02 16.64 Sn87Sb10Cu2Zn1 57.40±3.09 2.00 26.26±1.48 0.036±0.01 25.45 Sn86.5Sb10Cu2Zn1.5 60.02±4.92 0.005 28.12±9.40 1.00±0.02 33.20 Sn86Sb10Cu2Zn2 80.00±1.07 0.006 24.46±4.47 0.082±0.02 34.40 Sn85.5Sb10Cu2Zn2.5 77.80±1.07 0.01 32.70±3.35 0.079±0.02 37.32 Table (2):- Physical properties of Sn90-2x–Sb10Cu2Znx (X=0.5, 1, 1.5, 2 and 2.5 wt %) alloys.