Continuous Plasma Ball Milling for Uniform Powder Treatment
Solution Overview
Problem
Current low-temperature plasma technologies face limitations in large-scale powder preparation due to restricted discharge distances and high voltage requirements, which hinder the application of plasma-assisted ball-milling for metal and oxide ceramic powders, leading to incomplete and non-uniform treatment.
Innovation Solution
A continuous low-temperature plasma powder treatment and ball-milling device utilizing a powder circulating and conveying pipeline system, a low-temperature plasma discharge pipeline, and a controllable atmosphere system, enabling a double-dielectric barrier discharge structure for stable, high-energy plasma generation over long distances, combined with mechanical ball milling for uniform treatment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the ball-milling tank volume is increased to enable large-scale powder preparation, then the processing capacity is improved, but the discharge distance between electrode rod and pipe wall increases, making plasma discharge difficult and requiring excessively high voltage (>40 KV) which sharply reduces electrode life
Solution Approach 1:
The patent divides the single discharge space into multiple discharge spaces by installing multiple electrode rods within the ball-milling tank. Each electrode rod creates a separate discharge zone with controlled discharge distance to the pipe wall, preventing the need for excessively high voltage even when the overall tank volume is large. This segmentation allows large-scale powder preparation while maintaining reasonable discharge distances and electrode life.
2Manufacturing precision
If multiple electrode rods are installed to create multiple discharge spaces, then the plasma treatment uniformity is improved, but the device complexity increases
Solution Approach 1:
The patent makes the ball-milling tank itself serve multiple functions: it acts as both the milling chamber and the grounded electrode for plasma discharge. The pipe wall that forms the tank boundary serves as the common grounded electrode for all multiple electrode rods. This multi-functionality reduces device complexity by eliminating the need for separate grounded electrode structures while achieving uniform plasma treatment through multiple discharge zones.
3Length of stationary object
If conventional dielectric barrier discharge is used, then the discharge distance is limited to small values, but this restricts the ball-milling tank volume to below 10 liters, limiting large-scale application
Solution Approach 1:
The patent transitions from a single-point discharge approach to a distributed multi-point discharge approach by installing multiple electrode rods at different positions within the tank. This dimensional change in discharge spatial distribution allows the system to achieve effective plasma treatment in large-volume tanks without being constrained by the limited discharge distance of conventional single-point dielectric barrier discharge configurations.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach achieves uniform and efficient surface treatment of all powder particles, enhancing material properties through synergistic plasma and mechanical processing, overcoming previous limitations in discharge distance and energy control, and enabling large-scale preparation of metal and oxide ceramic powders.
Implementation Method 1
Dielectric barrier discharge is a common way of the low-temperature plasma, and is to fill a certain working gas between two discharge electrodes and add an insulating medium. When a sufficiently high alternating-current voltage is applied between the two electrodes, the gas between the electrodes will be broken down to discharge.
Implementation Method 2
The plasma is a fourth state of a material except a solid state, a gas state and a liquid state, and is composed of atoms, molecules, ions and free radicals with an equal number of positive and negative charges. The excitation of the plasma is mainly a quasi-neutral gas which is composed of a large number of positive and negative charged particles, electrons and neutral particles and free radicals generated by ionization of molecules when sufficient energy acts on the gas molecules
Implementation Method 3
combined with mechanical ball milling for uniform treatment
Data Source
AI summary
Disclosed are a continuous low-temperature plasma powder treatment and ball-milling production device, and a method thereof. The device includes a powder circulating and conveying pipeline system (1), a ball mill (2), a low-temperature plasma discharge pipeline (3), a vacuum discharge system (4) and a controllable atmosphere system (5), where the powder circulating and conveying pipeline system (1) is sequentially connected to the ball mill (2) and the low-temperature plasma discharge pipeline (3) through pipelines; and the controllable atmosphere system (5) is connected to the powder circulating and conveying pipeline system (1). The powder circulating and conveying pipeline system (1) is used for circulating and conveying to-be-treated powder at a controllable air pressure and flow speed. On one hand, a double-dielectric barrier discharge structure is introduced in a powder conveying process to form the low-temperature plasma discharge pipeline (3), thereby realizing a plasma discharge treatment on a transfer material powder; and on the other hand, the ball mill (2) is introduced to perform ball-milling refining or alloying on a powder subjected to plasma discharge treatment, thereby treating the powder through a large-area, uniform and high-energy non-equilibrium plasma in cooperation with mechanical ball milling and being capable of being used for performing a surface circulating modification treatment on a conventional metal, macromolecule or oxide powder.