How does the mixture homogeneity affect the physical, thermal and electrical properties of the end product? When blended in a V-blender machine, how the blending speed affect the homogeneity?
It is like having a cake with holes and tunnels inside it. It can be overly dense, or too spongy. Can always fill the holes with frosting to cover them up, but of course preventing them in the first place is the better plan.
Homogeneous mixture of metal powders result in better flow rate, green strength and uniform density of the compact throughout. Irregularity in powder mixture may result in final product with poorer properties.
Thank you for the reply. Is there any possibility that the mixing speed of the metal powder using the V-blender machine will has effect on the mixture homogeneity?
speed and time play major rules. Not to forget quantity of sample, mixing medium (ball or pallet if available), quantity and size of mixing medium, mixing atmosphere (if possible) etc. Propose to start a design of experiment to identify the main factors and the interactions between the main factors. Best of luck!
Let say the experiment to determine the effect of speed under constant rotation time.
1. The speed of rotation to be use is 15rpm, 25rpm, 35rpm and 45rpm.
However, there is some doubt whether the powder mixing in a table top V-BLENDER is suitable to rotate at speed higher than 30rpm.
I doubt you will observe any significant difference between the 15rpm sample and 25rpm sample, or between 25rpm and 35rpm. There is not much different in speed here. You know what, one of my student did almost the same experiment before. But instead of running with preset speeds, she played around with 10 different speeds or so. Then she observed how the powder changed after each rotation speed. Finally she selected the speeds that gave the "different" observations. By doing so, not only she had a solid reason why to selected a-rpm, b-rpm or c-rpm for her experiments, but she also managed to came out with very interesting results.
Thank you for the information. So, I need to use more variation of speed for the rotation and that is interesting. Thank you very much.
Energy absorbed by the powder particles during the mixing/blending has a significant effect on the morphology, crystallite size, crystalline or amorphous phases and the packing density. This energy in terms of rotational speed, time , intervals and milling media used etc. can be calculated and related later to find its effect on the parameters discussed above.
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