Microstructural Evolution and Mechanical Properties in Directionally Solidified Sn–10.2 Sb Peritectic Alloy at a Constant Temperature Gradient

Abstract

The Sn-10.2 Sb (mass fraction) peritectic alloy was prepared using a vacuum melting furnace and a hot filling furnace. The samples were directionally solidified upwards at steady state conditions with a constant temperature gradient (G=4.5±0.2 K. mm -1 ) under different growth velocities (V=13.3-266.7 µm. s -1 ) in a Bridgman-type directional solidification apparatus. The effects of the growth velocity (V) on the dendritic spacings were investigated. Primary dendrite arm spacing (PDAS) of α phase in directionally solidified Sn-10.2 Sb peritectic alloy was measured on the longitudinal and transverse sections of 4 mm diameter cylindrical samples. Secondary dendrite arm spacing (SDAS) was measured on the longitudinal section. The experimental results show that the measured PDAS (λ 1L , λ 1T ) and SDAS (λ 2 ) decrease with increasing growth velocity. The dependence of PDAS, SDAS, microhardness (HV) and compressive strength (σ c ) on the growth velocity were determined by using a linear regression analysis. The experimental results were compared with the previous experimental results and the results of the experimental models.

Influences of Growth Velocity and Fe Content on Microstructure, Microhardness and Tensile Properties of Directionally Solidified Al-1.9Mn-xFe Ternary Alloys

“…Using the vacuum melting and hot filling furnaces 12,13 , Al-1.9Mn-xFe alloys (x=0.5, 1.5 and 5 wt.%) alloys have been prepared under vacuum atmosphere by using 99.99 % purity metals taking into account the phase diagram as shown Fig. 1 14 .…”

“…2). The block diagram of the experimental design and details of the Bridgman-type directional solidification furnace are given in previous studies 12,13 . In the experimental technique, the sample was heated about 100 K above the melting temperature and solidification of the samples was carried out at a constant temperature gradient, G (6.7 K/mm) under various growth velocities (8.3-978 μm/s) in a Bridgman-type directional solidification furnace.…”

Effects of strain-induced melt activation treatment on the microstructure and properties of Zn sacrificial anodes

“…7 highlight the importance of the increase of Al content in the grain boundaries. Aluminum commonly promotes dissolution uniformity and reduces undissolved Zn anodes' mechanical detachment risk [3]. In addition, aluminum is added along with silicon to the sacrificial anode to control the detrimental effects of iron [31].…”

“…Technical challenges, such as melt combustion, severe oxidation, and high vapor pressure of Zn, hinder the accurate control of the aforementioned critical factors. In the preparation of sacrificial anodes, the final composition of the anode should match the desired specifications [3]. Some findings have shown that special structures, such as coaxial structures, exhibit better corrosion behavior than dendritic and columnar structures [4−5].…”

Cu and Ag additions affecting the solidification microstructure and tensile properties of Sn-Bi lead-free solder alloys

“…This has been done to avoid using lead (Pb) in the alloy due of its inherent toxicity [1,2]. Work into finding lead-free joints includes Sn-based alloys such as Sn-Bi [3], Sn-9Zn [4], Sn-10Sb [5], Sn-3.5Ag [6], Sn-0.7Cu [7] and Sn-3Ag-0.5Cu [8]. Some of these environmental-friendly solders are characterized by high melting temperatures (Sn-0.7Cu (227 o C), Sn-3.5Ag (221 o C) and Sn-3Ag-0.5Cu (217 o C)) which can damage the other electronic components attached to the printed circuit board (PCB) during reflow soldering operations.…”