The blank is the initial state of the part, and the part is formed by the blank according to various technical requirements after a variety of processing and the final formation. The choice of blank not only affects the manufacturing technology and business costs, but also has closely relationship with the parts of the machining technology and processing quality. Therefore, it is necessary to closely cooperate with the technicians in both the blank manufacturing and the mechanical processing to determine the material, structure, shape and size of the blank rationally.
Material selection to meet the requirements
Mechanical products are made up of several parts, to ensure the use of parts requirements is the basis to ensure the use of products. Therefore, the blank selection must first meet the performance requirements of the parts.
- Structural shape and size requirements
Mechanical parts due to the use of different functions, the structure of the shape and size are often different, a variety of blank manufacturing methods for parts shape and size of the adaptability is not the same. Therefore, the choice of blank should carefully analyze the structure of the part shape and size characteristics. Choose the appropriate manufacturing method of the blank.
- Mechanical properties of materials
According to the parts of the working conditions, damage (or failure) form, select the material to meet the mechanical properties
- Material process performance
The production of parts has a direct impact, even decisive.
- Surface quality requirements
In order to reduce production costs, some non-mating surfaces on modern mechanical products tend to be as raw as possible with less, no-chip processing.
The basic process of blank material selection
Starting from the service conditions of the blank material, the preselection of the material is completed by analyzing the failure mode, and the failure mode begins with the mechanical properties, process performance and economy of the material. After the preselection of the finished material, the design of the part and the calculation of the main parameters are to be carried out, mainly considering the durability of the material, the rationality of the structure size and the deformation and fracture resistance of the material, and finally the blank material is selected.
Blank material selection results
According to the above selection requirements, generally used in the processing of shaft parts of the rough material is mostly 45 steel, mainly due to 45 steel for the quality of carbon structural steel, hardness is not high, easy cutting, commonly used to prototype, connecting rod, bolts, gears and shafts, etc., and they need to make heat treatment.