(1) Aluminum material: Aluminum material is one of the nonferrous metals in the metal category. Due to its wide application, aluminum profiles are widely used in furniture: screen skeletons, various suspension beams, table legs, decorative strips, handles, walking The trunking, cover, chair tube, etc. can be designed and used in a variety of ways! Introduced separately as follows:
There are two types of aluminum profiles and die-cast aluminum alloys. Among them, aluminum ingots with a purity of more than 92% are mainly used as the main raw materials, and metal elements such as carbon, magnesium, silicon, and sulfur are added to increase strength, hardness, wear resistance and other performance elements to form a variety of alloys.
1.1 Aluminum profiles: Aluminum profiles are commonly used such as screens, aluminum windows, etc. It uses an extrusion molding process, that is, aluminum ingots and other raw materials are melted in a furnace, extruded through an extruder to die outflow molding, it can also extrude Profiles of different cross-sections. The main properties, namely strength, hardness and wear resistance, are in accordance with the national standard GB6063.
Advantages: Light weight of only 2.8, no rust, fast design changes, low mold investment, and longitudinal extension of up to 10 meters. The appearance of aluminum profiles is divided into bright and matte. The treatment process adopts anodizing treatment, and the surface treatment oxide film reaches a thickness of 0.12m / m. The thickness of the aluminum profile is selected according to the optimization of the product design. It is not that the thicker the market, the better. It should be designed based on the cross-sectional structure requirements. It can vary from 0.5 to 5 mm. The layman thinks that the thicker the tougher, it is actually a wrong view.
Disadvantages: warpage, deformation, black lines, bumps and white lines. The designer with high level and the reasonable mold design and production process can avoid the above defects. The inspection of defects should be carried out according to the inspection method prescribed by the state, that is, the sight distance is 40 ~ 50CM to identify the defects. Aluminum materials that have not been oxidized are prone to "rusting" and result in reduced performance. They are inferior to iron products in longitudinal strength. The wear resistance of the surface oxide layer is easier to scratch than the electroplated layer. The cost is higher.
1.2 Die-casting aluminum alloy
Compared with the processing method of die-casting alloy and profile, the equipment used is different. Its raw materials are aluminum ingots (about 92% purity) and alloy materials, which are melted by the furnace and enter the mold of the die-casting machine. The shape of the die-cast aluminum product can be designed like a toy, with different shapes and convenient connection in all directions. In addition, it has high hardness and strength.
The die-casting aluminum forming process is divided into:
1. Die-casting
2. Rough polishing to remove mold remnants
3. Fine polishing
(2) Hardware: The concept of "hardware" is a popular saying. The standard classification should be divided into two categories: ferrous metal and non-ferrous metal. It is used in furniture in tube, rod, plate, line, and angle.
2.1 Ferrous metal parts
Mainly refers to iron products.
Advantages: deformation resistance, high strength, good wear resistance, high hardness, low price and long life. It is a carbon iron alloy, which is divided into high carbon steel, low carbon steel, and medium carbon steel; it is divided into round tube, square tube, angle iron, and steel plate. Round tubes are mainly used for chair products; square tubes are used for beams and brackets; steel plates are mainly used for baffles, screen panels, pendants, support arms, metal cabinets, doors, etc. for tables and tables.
Disadvantages:
1. Easy to rust
2. Heavy volume
3. Fear of moisture
(The methods to solve the above defects are electroplating, spraying, black hair treatment, etc.)
There are many processing methods for hardware: bending, punching, drilling, welding, cutting, and pressing. In short, it is processed according to design requirements or product requirements.
2.2 Non-ferrous metal parts
Refers to all metal parts except iron products such as: aluminum, copper, zinc, stainless steel, etc. It has a characteristic that it is not easy to rust, and its strength is worse than ferrous metal. It is used more in furniture: aluminum plate, aluminum rod, stainless steel tube, stainless steel plate, copper plate, zinc plate.
Stainless steel parts: Stainless steel parts are divided into two categories: stainless steel and stainless steel: often called "430" as stainless iron, "304" as pure stainless steel, one of the methods to distinguish them: use magnet test, "430" can be magnet Suck, but "304" can't. The proportion of stainless steel parts is slightly higher than that of iron products, but the price is 4 times higher than that of iron products. Therefore, only high-end products are used
Copper products: Copper products are divided into pure copper and copper alloys. Pure copper, also known as red copper, has poor strength and hardness, but good toughness. The copper alloy used in furniture is mostly brass, which is a zinc-containing main alloy copper. The price of pure copper is slightly higher than that of "304" stainless copper, which is 30-40%, while that of brass is 20% lower than that of pure copper. The hardness and strength of copper alloy is slightly higher than that of stainless copper, but it is easy to break and brittle. The main copper parts used in furniture are handles and embedded screws. In order to prevent "rust", pure copper is generally used after electroplating, but brass is not needed, and large areas are used for furniture products
Zinc products: Pure zinc products are used less, mainly in combination with zinc alloys or steel. Such as galvanized sheet, electrolytic plate, etc. Less used in furniture because of the poor strength of zinc products. Zinc alloy fittings such as eccentric buckle, connection points (pieces) of structural parts, etc. The specific gravity of zinc alloy is slightly lower than that of iron by about 6.8, and the price is between steel and aluminum alloy. Most zinc alloys produce furniture parts in the form of die castings
Titanium and zirconium alloys: These are more expensive metals. They are mostly used in furniture in the form of electroplating. They are used in high-end handles, hinges and high-end exposed connectors or hotel furniture. The cost of electroplating is about 40% higher than the cost of chrome plating, but the appearance is high-grade similar to gold and silver products, wear resistance is very good, will not rust
2.3 Casting metal
Many furniture hardware products use castings, such as handles, door hinges, etc. In 2007, there are many casting production methods popular in the market, such as: precision casting process, die casting process, casting process. Casting materials include brass, stainless steel, zinc-tin alloy, and aluminum alloy. Casting product features: exquisite, special shape, etc. The disadvantage is that the cost of a single piece is high, the cost of different castings is different, roughly high to low, precision casting die casting, mold cost is high to low: die casting precision casting. The shortcomings of casting products are: the production cycle is slightly increased, and the products have to undergo 2 to 3 processes to make qualified accessories, and the accessories must be subjected to surface decoration treatments such as electroplating, polishing, wire drawing, sand blasting, and oil spraying according to different requirements.
(3) Rubber and plastic
3.1 Plastic parts
The application of plastic products in furniture is very common, and there are many types of materials: ABS, PP, PVC, PU, POM, PA, PMMA, PE, PS, PC, different materials have different adaptation ranges.
ABS: Commonly known engineering plastics, which can be used for connecting parts, seat backs, and seat plates. It is the main raw material of plastics that can be electroplated (water plated).
PP: Common name polypropylene, used for five-star feet, armrests, foot pads and connectors with low strength requirements. Disadvantages: poor wear resistance and low surface hardness.
PVC: The common name is polyvinyl chloride, which is mainly used for edge banding and insertion conditions. It is suitable for extrusion molding. At the same time, PVC material is a non-combustible material in plastic parts. The temperature stability of processing molding is poor, especially the stability of color is not good.
PU: Common name polyurethane. Mainly used for armrest (foam) accessories.
POM: The popular name Saigang. Mainly used for wear-resistant parts such as foot pads, casters, door hinges, hinges, etc. The performance is wear-resistant and pressure-resistant, but the dimensional stability is poor.
PA: Common name nylon. Mainly used as foot pads, five-star claws, casters and other places with high wear resistance and long life requirements. Features: wear-resistant, pressure-resistant, high-strength indoor long service life, individual models such as PA66 high temperature resistance up to 2200, the disadvantage is that it is easy to change the performance under the sun, easy to break, and poor weather resistance.
PMMA :: Plexiglass (commonly known as Acrylic). There are five kinds of transparent materials in plastic, and PMMA is one of the most transparent. The workpiece smells of acetic acid when cutting. It is easy to deform and process. It can be shaped and bent by soaking in boiling water. Disadvantages: the surface is easy to scratch, the hardness is low, and it is easy to crack when bending, and the price is more than 20% higher than ABS.
PC: Commonly known as polycarbonate. This variety is also a transparent material with high surface hardness, scratch resistance, strong impact resistance, high strength, and good weather resistance (that is, it is not afraid of sunlight). The sun screen of the screen partition in the furniture is hollow extruded from this material. Features: The price is high, about 40% higher than PMMA.
