Precision grinding and precision machining of aerospace aluminum materials

As an aluminum alloy for precision grinding of aerospace aluminum materials, it is comparable to the strength of steel plates, but the density of aluminum alloy is only 1/3 of that of stainless steel. This lightweight, sturdy and tough aerospace grade metal is more than 3C industry at home and abroad. It is first used in the middle of the mobile phone to better protect the solidity and toughness of the fuselage. The workpiece is made by precision cutting and grinding with a CNC machine tool. The surface has been sandblasted. It is worth mentioning that the middle frame of both is made of aluminum-magnesium alloy. So how do you polish the precision aerospace aluminum material aluminum alloy?

Precision grinding and Precision Machining of aerospace aluminum materials. Current precision and ultra-precision machining precisions range from micron to sub-micron to nanometers, and are widely used in automotive, home appliances, IT electronic information high-tech fields, and military and civilian industries. At the same time, the development of precision and ultra-precision machining technology has also promoted the development of machinery, molds, hydraulics, electronics, semiconductors, optics, sensors and measurement technology and metal processing industries.

The concept and scope of precision and ultra-precision machining

Generally, machining is divided into three stages: general machining, precision machining, and ultra-precision machining. At present, precision machining refers to processing technology with a processing accuracy of 1 to 0.1 μm and a surface roughness of Ra 0.1 to 0.01 μm. However, this limit is constantly changing with the advancement of processing technology. Today's precision machining may be tomorrow. General processing. The problems to be solved by precision machining are: machining accuracy, including geometrical tolerance, dimensional accuracy and surface condition; second, processing efficiency, some machining can achieve better machining accuracy, but it is difficult to achieve high machining efficiency. Precision machining includes micromachining, ultra-fine processing, finishing processing and other processing technologies. Traditional precision machining methods include abrasive belt grinding, precision cutting, honing, precision grinding and polishing.

1. Precision cutting, also known as diamond tool cutting (SPDT), is processed by high-precision machine tools and single crystal diamond tools. It is mainly used for precision machining of soft metals such as copper and aluminum, which are not suitable for grinding, such as magnetic for computers. Drums, magnetic disks and metal mirrors for high-power lasers are 1 to 2 grades higher than the average machining accuracy.

2. Honing, honing head composed of oil sand bar, reciprocating along the surface of the workpiece under a certain pressure, the surface roughness after processing can reach Ra0.4~0.1 μm, preferably to Ra0.025μm, mainly used for processing cast iron. And steel, should not be used to process non-ferrous metals with low hardness and good toughness.

3. Abrasive belt precision grinding is the processing of workpieces with abrasive fabrics mixed with abrasives. It belongs to the category of coated abrasive grinding, with high productivity, good surface quality and wide application range.

4. Polishing is a kind of micro-machining of the surface of the workpiece by mechanical, chemical and electrochemical methods. It is mainly used to reduce the surface roughness of the workpiece. Common methods are: manual or mechanical polishing, ultrasonic polishing, chemical polishing, electrochemical polishing. And electrochemical mechanical composite processing. After manual or mechanical polishing, the surface roughness of the workpiece is Ra≤0.05 μm, which can be used for the polishing of planes, cylinders, curved surfaces and mold cavities. Ultrasonic polishing processing accuracy is 0.01~0.02 μm, surface roughness Ra0.1 μm. The surface roughness of chemical polishing is generally Ra ≤ 0.2 μm. Electrochemical polishing can be increased to Ra 0.1~0.08 μm.

5. Precision grinding and polishing through the abrasive and machining fluid between the workpiece and the tool, the workpiece and the lap are mechanically rubbed together to achieve the required size and precision of the workpiece. Precision grinding and polishing can achieve the precision and surface roughness that can not be achieved by other processing methods for metal and non-metal workpieces. The roughness of the surface to be polished Ra≤0.025 μm is small, the surface quality is high, and the precision grinding equipment Simple, mainly used for the processing of flat, cylindrical surface, gear tooth surface and sealing parts with sealing requirements. It can also be used for the finishing of gauges, gauge blocks, injectors, valve bodies and valve cores.

Ultra-precision machining is the processing of extremely high shape accuracy and surface finish on ultra-precision machine tools by using the strictly constrained relative motion generated between the part and the tool. The current ultra-precision machining refers to a processing technique in which the dimensional accuracy of the machined part is higher than 0.1 μm, the surface roughness Ra is less than 0.025 μm, and the resolution and repeatability of the machine tool positioning accuracy is higher than 0.01 μm. Micron processing technology and is developing towards nanoscale processing technology.

Precision grinding and precision machining of super aerospace aluminum materials. Precision machining includes micromachining, ultra-fine machining, finishing, finishing and other processing technologies. Micro-machining technology refers to the processing technology for manufacturing small-sized parts; ultra-fine processing technology refers to the processing technology for manufacturing ultra-small-sized parts. They are proposed for the manufacturing requirements of integrated circuits. Due to the small size, the precision is cut off. The absolute value of the dimension is expressed instead of the ratio of the processed dimension to the dimensional error. Finishing generally refers to a processing method that reduces the surface roughness and improves the mechanical properties of the surface layer. It does not focus on improving the processing accuracy. Typical processing methods include honing, grinding, super finishing and chipless processing. In fact, these processing methods not only improve the surface quality, but also improve the processing accuracy. Finishing processing is a new term proposed in recent years. It corresponds to finishing, which means reducing the surface roughness and improving the mechanical properties of the surface layer, as well as improving the processing accuracy (including size, shape, Positioning accuracy).