Effect of Bi‐content on hardness and micro‐creep behavior of Sn‐3.5Ag rapidly solidified alloy

Abstract

In the present paper, the influence of 1, 3, 5 and 10 % Bi (weight %) as ternary additions on structure, melting and mechanical properties of rapidly solidified Sn-3.5Ag alloy has been investigated. The effect of Bi was discussed based on the experimental results. The experimental results showed that the alloys of Sn-3.5Ag, Sn-3.5Ag-1Bi and Sn-3.5Ag-3Bi are composed of two phases; Ag 3 Sn IMC embedded in Sn matrix phase, which indicated that the solubility of Bi phase in Sn-matrix was extended to 3 % as a result of rapid solidification. Bi precipitation in Sn matrix was only observed in Sn-3.5Ag-5Bi and Sn-3.5Ag-10Bi alloys. Also, addition of Bi decreased continuously the melting point of the eutectic Sn-3.5Ag alloy to 202.6 ºC at 10 % Bi. Vickers hardness of Sn-3.5Ag rapidly solidified alloy increased with increasing Bi content up to 3 % due to supersaturated solid solution strengthening hardening mechanism of Bi phase in Sn matrix, while the alloys contain 5 and 10 % Bi exhibited lower values of Vickers hardness. The lower values can be attributed to the precipitation of Bi as a secondary phase which may form strained regions due to the embrittlement of Bi atom. In addition, the effect of Bi addition on the micro-creep behavior of Sn-3.5Ag alloy as well as the creep rate have been described and has been calculated at room temperature.

Structure and Properties of Sn-9Zn Lead-Free Solder Alloy with Heat Treatment

“…Also, reduction of the lattice strain leads to increase the hardness. Another point is noticed from this figure that the values of HV in all samples are decreased with increasing applied load, which well known as indentation size effect and agree with the results observed elsewhere [13,14].…”

Structure, Electrical Resistivity, Oxidation and Corrosion Behavior of Tin-Lead Eutectic Alloy

“…The electrical resistivity of the alloy sample was first calculated many times and the average value was taken into account. It was found that, the electrical resistivity is equal to 24.6 ± 1 µΩ.cm, which is a high value when compared with a wide range of lead-free solders [8][9][10][11][12][13][14][15]. After that, the circuit was connected to a heater plate and recorded the value of the voltage versus temperature in the range of the room temperature to 91 ºC then calculating the electrical resistance with temperatures as illustrated in Fig.(3.5).…”

Effects on Undercooling and Interfacial Reactions with Cu Substrates of Adding Bi and In to Sn-3Ag Solder

“…The effect of adding Bi on the thermal and mechanical properties of Sn-Ag-Bi solders has been explored extensively. [7][8][9][10][11][12] If In and Bi are both added to Sn-Ag solders, they compensate for each other, helping to maintain good mechanical properties. 13,14 Based on the literature, this investigation compares the interfacial reactions, the IMC growth kinetics, and the thermal properties of these Sn-Ag-In and Sn-AgBi solders, which react with Cu substrates, with reference to both kinetics and thermodynamics.…”