What is the electropolished smt stencil process?
Electropolished smt stencil is what process, it has what advantages compared with other smt stencil, today we do for you to do in-depth explanation, I hope to help you in the purchase of smt stencil suitable for their own factories really need.
What is electropolished smt stencil:
Electropolishing is also called electrolytic polishing, electrolytic polishing is electrochemical polishing, the use of tip discharge principle, energized state of the electrolyte as a medium to generate current on the surface of the workpiece to be polished so as to achieve a rapid increase in the brightness of the surface of the workpiece to reduce the surface of the smt stencil and the pore wall of the microscopic roughness.
Stencil electrolytic polishing process is an electrolytic process, electropolishing tank is an electrolytic tank, the stencil is fixed in the anode, immersed in electropolishing solution, through the high current. At this time, the surface of the stencil formed a thick viscous film with high resistivity, this layer of viscous film on the surface of the microscopic protruding part of the thickness is small, while in the microscopic concave at the thickness of the larger, therefore, the current density of the micro-distribution is also uneven, coupled with the tip effect of the current, so that the protruding part of the current density is very high, dissolved very quickly, while the concave part of the current density is very low, the dissolution of the slow, which makes the protruding part of the size decrease So that the size of the convex part decreases very quickly, and the size of the concave part decreases very slowly, so as to achieve the purpose of leveling and smoothing.
What are the advantages of electropolished smt stencil:
Laser cutting stencils are punched to form openings by dissolving stainless steel through the high energy of the laser due to the use of highly concentrated laser energy. This causes the laser stencil to have metal slag at the edge of the opening, and there will be the edge of the hole wall is not smooth and straight, so that the printing solder paste under the tin caused by the difficulties. In order to improve this disadvantage of the laser stencil, it is now achieved by electropolishing. The advantages are as follows:
- SMT stencil electropolishing can improve the cleanliness of the bottom surface of the stencil;.
- Electrolytic polishing can achieve the surface roughness and the original surface roughness, generally can be improved by two levels.
- The polished surface will not produce a metamorphic layer, so that the stencil is more flat, no additional stress, and can remove or reduce the original stress layer.
- Difficult to use mechanical polishing of hard materials, soft materials, as well as thin-walled, complex shape, small parts and products can be processed.
- SMT stencil electropolishing and polishing the hole wall at the same time, can make the surface friction reduction, good release of solder paste and the reduction of cavities;.
- SMT stencil polishing time is short, and can polish many pieces at the same time, high production efficiency.
- After the laser stencil is electropolished, the slag and burr in the hole wall will be removed or improved in the solution, which improves the ability of the stencil to lay tin.