Mekhanobr-Tekhnika Research & Engineering Corporation, Saint Petersburg, Russia:

M. V. Cherkasova, Lead Researcher, Candidate of Technical Sciences, e-mail: cherkasova_mv@mtspb.com
A. M. Gerasimov, Lead Researcher, Candidate of Technical Sciences
V. A. Arsentiev, Principal Researcher, e-mail: ava@mtspb.com
К. Е. Zhdanova, Engineer

Metal shavings generated by the machine building industry offer a promising material for making metal powders for metallurgy and additive manufacturing applications. A review suggests that mechanical disintegration could potentially be used for producing such materials. It takes a lot of energy to grind viscoelastic solids, i.e. metal shavings. This serves as a driver for looking for ways to intensify the disintegration process. A study that looked at the effect of environment on the mechanical grinding of solid materials showed that they can potentially be used for both protection and intensification. According to the outcomes of a previous study that looked at the grinding of metal shavings using inert gases and polymethylmethacrylate (PMMA), nitrogen and hydrogen serve as the most effective intensifiers. It would be of interest to find activators for the process in view that would have the same effect but would be cheaper and more convenient than PMMA. Thus, ammonia could serve as the easiest source of nitrogen and hydrogen. A study was conducted that examined the effect of ammonia on the grinding degree. A model of vibrating grinding mill IVS-4 designed by Mekhanobr-Tekhnika was used for experiments. The findings show that ammonia gas could potentially be used as a medium for fine grinding of metal powders, while no inert gases would be needed. The rate of vibration grinding of powders is higher in ammonia than in nitrogen: by 20% for steel and by 30% for aluminium. It is pointed out that, for the studied specimens, gas produces a noticeable effect on the powder morphology and rheology. However, this needs further study.
Support for this research was provided under a grant of the Russian Science Foundation; Project No. 20-79-10125.

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