What kind of material is needed for precision machining?

Precision machining is not what materials can be processed, some materials hardness is too large, more than the hardness of the processing machine parts, it may break the machine parts, so these materials are not suitable for precision machining, unless it is made of materials, or laser cutting.

Materials for precision machining are divided into two categories, metallic materials and non-metallic materials.

For metal materials, the hardness is stainless steel, followed by cast iron, followed by copper, and then aluminum.

The processing of ceramics, plastics, etc. belongs to the processing of non-metallic materials.

1, the material hardness requirements, for some occasions, the higher the hardness of the material is the better, but limited to the hardness requirements of the processing machine parts, the processed material can not be too hard, if it is harder than the machine parts can not be processed.

2. Secondly, the material is soft and hard, at least one grade lower than the hardness of the machine parts, and it also depends on what the role of the processed device is to do, and reasonable material selection of the machine parts.

In short, there are still some material requirements for precision machining, and not what material is suitable for processing, such as too soft or too hard materials, the former is not processed, and the latter can not be processed.

Therefore, the basic one is to pay attention to the density of the material before processing, if the density is too large, the equivalent of hardness is also large, and if the hardness exceeds the hardness of the machine parts (lathe tool), it can not be processed, not only will damage the parts, but also cause danger, such as the turning tool flying out to hurt people. Therefore, in general, for mechanical processing, the material material should be lower than the hardness of the machine knife, so that it can be processed.

Ordinary parts processing will involve surface roughness, surface waviness, surface processing texture and other geometric characteristics, parts processing is no more than this, that is, the requirements of all aspects are higher. Among these many geometric characteristics, surface roughness is the basic factor that constitutes the geometric characteristics of the machined surface, so it needs to be paid attention to.

In the process of parts processing, its surface roughness will be affected by three factors, mainly geometric factors, physical factors and numerical control processing technology. From the perspective of geometric factors, it mainly refers to the shape and geometric Angle of the tool, especially the radius of the tool tip, the main declination Angle, the auxiliary declination Angle and the feed amount in the cutting parameter have a greater impact on the surface roughness. At the same time, it is also necessary to consider the extrusion and friction of the cutting edge of the tool and the back, if the metal material is plastic deformation, it will seriously worsen the surface roughness. Especially when the plastic material formed ribbon chips, it is easy to form high hardness chip nodules on the front tool surface.

If the relationship between parts processing and performance roughness is analyzed from the perspective of process factors, there are mainly factors related to cutting tools, factors related to workpiece material and factors related to CNC machining conditions. If these factors can be controlled reasonably, the surface roughness after processing can also meet the requirements.

In fact, whether it is ordinary parts processing or parts processing, it is necessary to regulate the processing quality from the above three aspects, which is the basic condition for obtaining good processing quality.

Benchmark is used to determine the position of other points, lines, surfaces on the basis of the point, line, surface, according to the different functions of the benchmark, can be divided into two categories of design benchmark and process benchmark. Parts processing should also comply with these two aspects of the benchmark, so that the processed parts can meet the standard.

The design basis of parts processing refers to the basis used to determine the position of other points, lines and surfaces on the part drawing, such as the axle sleeve parts, the design basis of each outer circle and inner hole is the axis line of the part, the design basis of the end face A is the design basis of the end face B and C, the a axis of the inner hole is the basis of the radial runout of the outer circle. The process benchmark of parts processing is the benchmark used in the processing and assembly process of parts, which is divided into assembly benchmark, measurement benchmark and positioning benchmark according to different uses. The part assembly reference can be used to determine the position of the part in the part or product at the time of assembly.

Parts in the processing of parts are mainly used to test the size and position of the processed surface of the benchmark, such as the axis of the inner hole is to test the radial runout of the measurement of the benchmark; Surface A is the measurement basis for checking the length and scale. The positioning benchmark is the benchmark used in the positioning of the workpiece, as the positioning basis of the surface or line, point, in the process can only choose the unprocessed blank surface, in the various processes can be used in the machining surface as the positioning benchmark.