PSI - Issue 65

A.V. Sulitsin et al. / Procedia Structural Integrity 65 (2024) 282–289 A.V. Sulitsin, , S.V. Brusnitsyn, D.O. Levin, D.A. Usov, V.K. Dubrovin / Structural Integrity Procedia 00 (2024) 000–000

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It was found that when introducing magnesium-cerium ligature, there are no intermetallic clusters, the average size of which does not exceed 80 μm. The microstructure of the control ingot and with the addition of magnesium cerium ligature in an amount of 0.3 wt.% is shown in Fig. 1.

a

b

Fig. 1. The microstructure of alloy 70Cu-13Zn-7Mn-5Al-2Fe-2Si-1Pb (x200): control ingot (a); with addition of magnesium-cerium ligature in the amount of 0.3 wt. % (b).

In addition the Vickers hardness HV was determined for the cross-section of the control and experimental ingots. The results are shown in Fig. 2.

a

b

c

Fig. 2. The effect of modifiers on the hardness of ingots of alloy 70Cu-13Zn-7Mn-5Al-2Fe-2Si-1Pb: with addition of mischmetal (a); with addition of magnesium-cerium ligature (b); with addition of niobium (c).

Analysis of the results showed that when adding magnesium-cerium ligature in an amount of 0.3 wt.%, the hardness of the alloy increases by an average of 3% and is leveled in the cross section of the ingot. Thus, modification is an effective way to refine the structure and improve the mechanical properties of complex-alloyed brass, and the greatest effect is achieved when using magnesium-cerium ligature as a modifier. Since adding magnesium-cerium ligature is difficult due to the high chemical activity and low density of these elements, it is advisable to introduce them in the form of copper- or nickel-based ligatures. For example, a ligature of the composition 84Ni-15.5Mg-0.5Ce is known. It is used in the production of high-strength cast iron and is supplied to plants in pieces of 20...110 mm. The ligature ingots obtained at the manufacturing plant are crushed. This produces a significant amount of fine fraction, during the remelting of which significant metal losses occur with slag. To reduce the amount of irretrievable losses, it is necessary to search for alternative areas of application of the fine fraction of the Ni-Mg-Ce ligature. One of the possible options for using the fine fraction of the ligature is its use as a modifier for complex-alloyed brasses.