Nowadays, with the development of coatings and coating methods in China, there are many coating defects and it is difficult to find out the reasons. So far, there are many defects that are not known for what reason. More subtle is that some defects may occur, but It will disappear automatically after a while. The following expenditures may lead to factors affecting the appearance of coating defects, but the occurrence of defects is often caused by the interaction of multiple factors.
(1) the factors of the coating itself
As described above, the coating material is composed of a plurality of components such as a film-forming substance, a solvent, an auxiliary agent, and a coloring material, and a plurality of raw materials, and the properties thereof are composed of various components to achieve a complementary length. Usually, the formulated coating is in a quasi-stable state, so it is easily affected by various external conditions, such as improper storage environment, long storage time, viscosity increase or solidification, which is due to the tendency of the coating to self-compact. The inevitable result of the unstable state. Another example is the unreasonable design of the coating formulation, improper selection of raw materials, problems in the manufacturing process, inspection, shipment, packaging, transportation and so on. In particular, the coating is carried out according to the process specified by the manufacturer's product specification, and defects still occur. At this time, the cause of the coating can be found.
(2) Influence of substrate properties
As mentioned above, wood and wood materials are uniquely coated substrates, which are water-containing (moisture-moving), porous, non-uniform in material and material, and have many factors that cause defects. Unrepaired solid wood substrates themselves have many defects (worm eyes, cracks, roughness, fat, oil, etc.) that will directly cause coating defects. The high moisture content of wood and the continued movement of moisture into and out of the wood not only cause various defects before and after painting, but also cause the cracking and damage of the paint film after the use of wood products. Therefore, wood coating must first fully understand the wood, and then do the quality management of the wood coating to reduce the possibility of many defects. Therefore, when a coating defect occurs, the factor of the substrate cannot be ignored.
(3) Coating process factors
When the factors of coating and substrate can be controlled and eliminated, the defects are mostly caused by unreasonable design of the coating process and imprecise implementation. The coating process here includes the specific coating process, the methods and tools used in each process, especially the procedures of repeated processes such as dry grinding, and whether the process conditions and process parameters of various processes are normal and accurate. For example, the choice of coloring and filling materials, whether the bottom paint is matched, the proportion of paint adjustment, the type and dilution rate of the diluent, whether the tool and equipment are equal, the nozzle and air pressure of the spray gun, whether the function of the oil water separator is normal, etc. , especially the curing conditions of the coating (temperature, humidity, ventilation, dust removal, drying time and stage, etc.).
(4) Coating environmental factors
Wood coating, especially the coating of high-grade wood products, is a fine process, which requires a good environment. For example, the lack of lighting in the workshop will inevitably affect the accuracy of the line of sight. It may be discolored, the thickness of the spray is uneven, and it can be found in time and in time. Defects avoided (such as chromatic aberration, sag, uneven thickness, etc.) were not discovered in time. The temperature and humidity sprayed on the dry site are not controlled, the workshop is not well ventilated, or the wind speed is not suitable, solvent evaporation and solvent evaporation and paint mist are difficult to remove. In particular, the sanitary conditions of the spraying and drying sites are poor, the air dust is not cleaned enough, and the ceilings, walls, floors and clothing are still dusty. It also includes sawdust from wood machining, grinding debris from the substrate, and non-self-contaminated sources around the paint shop environment, especially air pollution with high lipids, passing through the air and falling on the coating.
(5) Coating technology factors
The painting project is implemented by the operator. The painting process relies on the design and management of technicians. The quality of engineering and technical personnel is poor. There is no basic theoretical cultivation of coatings, wood and painting processes. It is difficult to have no practical experience or work. Controlling the normal operation of the painting project, it is difficult to avoid defects. All of the above-mentioned influencing factors are solved by reliable human factors, so coating technology is also a key influencing factor.
AlNiCo material is comprised of aluminum,nickel,cobalt and iron with varying additions of other elements. There are two different manufacturing processes for AlNiCo:Cast and sintered. Cast AlNiCo can be made into many sizes and shapes,whereas Sintered AlNiCo is usually restricted to smaller sizes. However,both processes lead themselves to complex geometries and configurations. Standard Sintered AlNiCo has tighter dimensional tolerances due to its processing. It also has slighty lower magnetic properties,but better mechanical strength than Cast AlNiCo products. They are most suitable for small sizes that are less than 1 oz. It also results in parts that are structurally stronger than the cast Alnico Magnets. With the sintering process, one can achieve relatively close tolerances without any grinding.
Production: costing and powder metallurgy
Constitution: Al-Ni-Fe-Co
Performance: well performance in temperature stability
Processing: various sizes and shapes.
Application: Applied in instruments and other like fields..
The name of AlNiCo Magnets comes from its main compositions-Al, Ni, Co. They are made through casting and sintered. They are inexpensive and have wide temperature stability. Thus, compared to other permanent magnet materials, they have such obvious advantages as bellow:
1. solid and breakable
AiNiCo magnets
In the 1930s, early permanent AlNiCo magnets came into being and predominated over the Permanent Magnetic material due to its excellent properties. AlNiCo Magnet is a kind of alloy formed by Al, Ni, Co and other trace elements. Its function and magnetic performance vary because of different compositions of metals. There are two kinds of production, costing and sintered. Through costing, magnets can be manufactured into various sizes and shapes. But sintered is suitable for making small size of magnets. The dimensional tolerance of blanks by sintered is better and more workable than that by costing, but the magnetic properties are slightly lower than costing products. Among the magnetic materials, AlNiCo magnets have the lowest reversible temperature coefficient, and its working temperature is up to 600 ℃. AlNiCo magnets are commonly applied in all kinds of instrumentations and other fields.
Advantages:
1. High Frequency Induction Melting Technology. Our raw materials are in accordance with the standards of International Environmental Protection Organization (IEPO) and ROHS
2. A high standard of gold finishing techniques. The minimum tolerance can be ±0.01mm.
3. Thermal control of the directional columnar crystal ingot Technology.
4. Automatic Heating Equipment to make sure consistency of magnet properties.
5. Laboratory of Physics and Chemistry for studying the relation between AlNiCo properties and its constitution and developing new kind of magnets by using new achievements in scientific research.
Process flow sheet
sintered AlNiCo
Raw materials → ingredients → magnetic powdering → pressing →sintered → heating → magnets test → → products test → packing
Costing AlNiCo
Raw materials → ingredients → melting → costing → heating → magnets test → → products test → packing
AlNiCo Magnets
AlNiCo Magnet, AlNiCo Magnets, Alnico Bar Magnets, Alnico Ring Magnets, Alnico v Magnets
China-Base Ningbo Foreign Trade Co.,Ltd. Ningbo Songko(CBNB) Magnetic Material Co., Ltd. , http://www.cbnb-magnets.com