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ArticleName Microstructure and mechanical properties of ML10 (NZ30K) magnesium alloy which is used as a raw material for the castings production
DOI 10.17580/tsm.2017.07.11
ArticleAuthor Koltygin A. V., Bazhenov V. E.

National University of Science and Technology MISiS, Moscow, Russia:

A. V. Koltygin, Assistant Professor of a Chair of Casting Technologies and Art Material Processing
V. E. Bazhenov, Assistant Professor of a Chair of Casting Technologies and Art Material Processing, e-mail:


The ML10 (NZ30K) magnesium alloy is usually melted from MZr1N3 (bal. Mg, 1wt.% Zr, 3wt.% Nd) by adding Mg – 15wt.%Zr (L2 or L4), Mg –20wt.%Nd (МN) master alloys and pure zinc. Solikamsk Experimental Magnesium Plant was the first manufacturer of magnesium alloys that offered the ML10 alloy ingots on the Russian market. Two samples of the ML10 alloy, manufactured by Solikamsk Experimental Magnesium Plant, were investigated. Alloy ingots come in rectangular and cylindrical shapes. The alloy microstructure is typical for the as-cast ML10 alloy. However, in the sample that was cut off from the ingots edge, the level of zinc and neodymium was maximal, whilst the level of zirconium was minimal. On the other hand, the level of zinc and neodymium was minimal in the samples that were cut off from the center of the ingots, whilst zirconium level was maximal. Furthermore, the level of neodymium in the center of the ingot was below the standard limit. Furthermore, a segregation of ingot components must be considered during the alloy preparation. A cylindrical ingot was melted and bars were cast and heat treated. The bars were heat treated according to T4 (solution-treated at 530–540 °C for 8 hours) and T6 temper (solution-treated at 530–540 °C for 8 hours, air cooled, and then aged at 200 °C for 8 hours). The mechanical properties were determined, using cylindrical samples, machined from the bars with 10 mm diameter. ML10-T6 alloy has the tensile strength σв = 232±16 MPa, yield strength σ0,2 = 151±15 MPa, and elongation δ = 6.8±1.8%. Hardness of the ML10-T6 and ML10 T4 alloys is 68 HB and 57 HB, respectively. The ML10-T6 alloy fractures were investigated. The fracture is typical for the ML10 alloy. The fracture does not contain non-metallic inclusions, which means that the alloy is pure. The loss of alloying elements from the melt during the melting process was determined. In case of a 3-hour holding of the ML10 alloy in the steel crucible under a protective flux cover and at the temperature of 760–780 °C, the levels of neodymium and zirconium were reduced by 0.3% and 0.22%, respectively. The level of zinc did not change during the holding. The investigated alloys are recommended as raw materials for producing castings of the ML10 alloy in a production environment.

keywords Magnesium alloys, ML10, NZ30K, raw material, melting, melting loss, mechanical properties, master alloy

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