Kinetic interactions between solid iron and molten aluminium

Morphology of Compounds Formed by Isothermal Reactive Diffusion between Solid Fe and Liquid Al

“…8. In this figure, the ordinate indicates z, and the abscissa shows the logarithm of t. On the other hand, the results of T ¼ 973 and 1073 K reported by Bouché et al 69) are indicated as open squares and rhombuses, respectively, and that of T ¼ 1073 K reported by Bouayad et al 71) is shown as open double-circles. For convenience' sake, the present study is called study A, and the studies by Bouché et al and Bouayad et al are designated studies B and C, respectively.…”

“…[62][63][64][65][66][67][68][69][70][71][72] In an experiment by Bouché et al, 69) Fe/Al diffusion couples were prepared by a melt bath technique, and then isothermally annealed at temperatures of 973-1173 K. A similar experiment was conducted by Bouayad et al 71) In the binary Fe-Al system, 1) FeAl 3 , Fe 2 Al 5 , FeAl 2 and FeAl are the stable compounds at these temperatures. According to their experimental results, 69,71) however, only Fe 2 Al 5 and FeAl 3 are formed as visible layers at the Fe/Al interface in the diffusion couple owing to annealing. The thickness is much smaller for the FeAl 3 layer than for the Fe 2 Al 5 layer, and irregular tongue-like morphology is realized for the Fe 2 Al 5 layer.…”

“…Thus, in the isothermal bonding technique, the temperatures of the melt and the solid specimen are equivalent and remain constant during preheating, bonding and annealing. On the other hand, in the melt bath technique, 69,71) the solid specimen is preheated at a certain temperature lower than that of the melt, and then immersed in the melt for annealing. During annealing, compound layers are formed at the interface between the solid specimen and the melt.…”

The Influence of Grain Structure on Intermetallic Compound Layer Growth Rates in Fe-Al Dissimilar Welds

“…These lightly pre-welded samples were then isothermally annealed in the temperature range 673 K to 843 K (400°C to 570°C ) for times increasing up to 8 hours. Metallographic cross sections were prepared from the welded and heat-treated samples by grinding and polishing, using standard techniques, before observation Bouayad et al [13] 74.1 1073 (800) pure Al*-pure Fe Denner and Jones [14] 170-195 1044 (771) pure Al*-Mild steel Eggeler et al [15] 34-155 1059 (786) pure Al*-Low carbon steel Naoi et al [6] 281 873-923 (600-650) pure Al-pure Fe Springer et al [3] 190 873 (600) pure aluminum-low-carbon steel Tang et al [16] 123 953-1043 (680-770) pure Al*-pure Fe by scanning electron microscopy (SEM) using a high-resolution FEI Magellan field emission gun (FEG) microscope. The average layer thickness was determined from the net area of the IMC layer divided by the interface length.…”

Influence of Filler Alloy Composition and Process Parameters on the Intermetallic Layer Thickness in Single-Sided Cold Metal Transfer Welding of Aluminum-Steel Blanks

“…[20,21] Among the Al x Fe y phases listed in the binary Al-Fe phase diagram, [35] two main phases were identified in laboratory experiments to form at the interface between solid iron or steel and liquid aluminum or its alloys: Al 5 Fe 2 as the major g-phase [36][37][38] together with Al 3 Fe (also referred to as Al 13 Fe 4 ) as the minor h-phase. [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55] Both [17][18][19]21,24,27,29] or at least either one [22,23] of these two phases were also found to form during dissimilar CMT welding of aluminum alloys with steel. These experimental studies also show that the interfaces are typically tongue-like between Al 5 Fe 2 and steel, whereas they are finely serrated between Al 3 Fe and aluminum.…”