Mechanical alloying (MA) is a relatively novel method that has been successfully applied for materials, such as intermetallic compounds and transition metal carbides, which are difficult to synthesize because of their high melting temperatures.
I would say that different mechanical alloying processes are repetible in laboratory and small or medium size equipment. In my experimental work we performed several so called milling kinetics experiments and the trend in phase evolution - measured by ex-situ Xrd and/or moessbauer spectroscopy was nearly always the same, apart from a set of experiments that was carried in winter in a laboratory without heating. My Colleague and friend Francesco Delogu has been proposing over the year a model based on the number of impacts which seems quote general. Much depends on heat effects.. endothermic Solid state reactions have a sigmoidal ( typically modeled with a logistic curve) trend with time. On the other hand, reactions which are exothermic are more difficult to be described..
Generally, repeatability entails in the possibility of exact reproduction of process, controls and results. Due to the complexity of the dependencies of results on process and control parameters, it obviously is very difficult to reproduce any mechanical alloying process with same parameters, controls and results. However, reprucibility becomes less difficult if the work is carried out on a laboratory scale. Thus one can affirmatively say yes processes are reproducible under certain conditions
From my experience, I would agree that there is good repeatability. I have only worked in small quantities, however. Ball milling is extremely sensitive to the setup and you will have to use the same milling parameters. Therefore, the ball to powder ratio, ball size and material, milling time and rotation speed, even the particle sizes of the individual elements have to be the same for good repeatability of the experiments.
Dear Amin, MA is 100% repeatable and an old method for production of some materials and compound, but recently being excavated by researchers to synthesize unique and high temperatures carbides, borides , and ....
MA has industrial applications in cement Pb-Acid batteries production.
Dear Arman, I got a general response.
I need to more detail and evidences.
Armin Rajabi
This process is repeatable technically but there is a problem which is cold welding of materials to the walls of the jars. This will result in slightly different chemical composition of different batches of the alloys you make with your setup. Although there are some materials such as oily acids that will help to prevent cold welding, still the different components of the powders have different mechanical and chemical properties and behavior which might result in a deviation of what was expected. But in general, based on my experience, it would be technically possible but not physically.
Yes. Indeed It is repeatable. You can just take example of ball milling.
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