Special processing refers to those processing methods that are not in the traditional processing technology category.
It is different from traditional processing methods that use tools, abrasives, etc. to directly remove excess material using mechanical energy.
Special processing is a new process developed in recent decades.
It is an important supplement and development of traditional processing methods. It is still under continuous research and development.
Direct use of electrical energy, thermal energy, acoustic energy, light energy, chemical energy and electrochemical energy, sometimes combined with mechanical energy to process the workpiece.
In special processing, EDM and electrolytic processing, which are mainly based on electric energy.
It is widely used, and are generally called electric machining.
The EDM process invented in the 1940s created a method of machining hard workpieces with soft tools and without mechanical force.
After the 1950s, electron beam processing, plasma arc processing and laser processing appeared.
These processing methods do not use forming tools, but process them with a very dense energy beam.
For high hardness materials and complex shapes, precise and fine special parts, special processing has great applicability and development potential.
It is used more and more widely in the manufacture of molds, measuring tools, blades, instrumentation, aircraft, spacecraft and microelectronic components.
The development direction of special processing is mainly:
- Improve machining accuracy and surface quality
- Increase productivity and automation
- Develop composite processing using several methods in combination
- Develop nano-scale ultra-precision machining, etc.
- It has nothing to do with the mechanical properties of the processed object.
Some processing methods, such as laser processing, EDM, plasma arc processing, electrochemical processing, etc., are the use of thermal energy, chemical energy, electrochemical energy, etc.
These processing methods are independent of the mechanical properties such as the hardness of the workpiece, so they can process a variety of hard and soft, brittle, heat sensitive, corrosion resistant, high melting point, high strength, special properties of metal and non-metallic materials.
- Non-contact processing.
Not necessarily a tool.
Some use tools, but they are not in contact with the workpiece.
Therefore, the workpiece does not receive a large force, and the hardness of the tool can be lower than the hardness of the workpiece, so that the extremely low rigidity component and the elastic component can be processed.
- Micro processing.
The surface quality of the workpiece is high.
Some special processing, such as ultrasonic, electrochemical, water jet, abrasive flow, etc., the machining allowance is fine, so not only can process small holes or slits, but also obtain high-precision, extremely low-roughness machining surfaces.
- There is no mechanical strain in processing or large area thermal strain.
A lower surface roughness can be obtained, and thermal stress, residual stress, cold work hardening, etc. are relatively small, and dimensional stability is good.
- Two or more different types of energy can be combined with each other to form a new composite processing, and the comprehensive processing effect is obvious, and is convenient for popularization and use.
- Special processing has a positive impact on simplifying the processing technology, changing the design of new products and the structural and processability of parts.