Forging characteristics of automobile forgings
Apr 20, 2023| Forging characteristics of automobile forgings
Automobile forging refers to the automobile parts produced by forging process, which has the characteristics of high strength, high toughness, high hardness, high wear resistance, high precision, high heat resistance, fatigue resistance and so on. Automobile forgings are widely used in automobile engine, transmission, steering gear, suspension system, frame and other parts, its design, materials, manufacturing, technology and detection and other aspects have its unique. This paper will analyze the forging characteristics of automobile forgings in order to better understand the production and application of automobile forgings.
1. Material characteristics of automobile forgings
The materials of automobile forgings are generally quenched and tempered steel, carbon steel, alloy steel, stainless steel and other metal materials. These materials have some common characteristics, such as high strength, good plasticity, good fatigue resistance, weldable, machinable, easy to obtain, etc. When forging automobile parts, it is necessary to consider the thermal effects of materials, such as grain growth, hardness reduction, microstructure uniformity affected, etc.
Two, the design characteristics of automobile forgings
The design of automobile forgings should meet the requirements of safety, reliability, economy, easy manufacturing, easy disassembly and maintenance. In the design of automobile forgings, the force, structural characteristics, working environment and fit clearance must be taken into account. Especially for high pressure, high temperature, high speed and high load parts of the design requirements.
3. Manufacturing process characteristics of automobile forgings
The manufacturing process of automobile forgings adopts hot working technology, among which forging is the main process. Forging process has the following characteristics:
1. Plastic deformation of metal materials to increase its strength, hardness and wear resistance in the process of processing;
2. Simple process, high machining precision, precision forging can be realized;
3. High efficiency and high output;
4. Can manufacture large, high strength, ultra-precision and complex shape parts;
5. Suitable for all kinds of metal materials.
There are many kinds of forging process, such as hammer forging, spiral forging, extrusion forging, bending forging, precision forging, special forging and so on.
1. Hammer forging
Hammer forging is a traditional forging process, which uses hammer, punch and other equipment to forge. Hammer forging has the following technical characteristics:
(1) The forging process is intermittent and the number of hammering can be adjusted;
(2) high forging precision, no need for local tempering;
(3) Low forging cost, suitable for mass production.
Hammerhead forging is generally used in the production of small and medium-sized automobile forgings, such as gear, camshaft, connecting rod, crankshaft, etc.
2. Screw forging
Screw forging is a forging process using screw forging machine. Unlike hammerhead forging, spiral forging is a continuous forging process in which the billet is rotated by a spiral shaft and forged between relatively stationary dies. Screw forging has the following technical characteristics:
(1) The forging force is relatively small, can avoid excessive deformation;
(2) Good process continuity and high production efficiency;
(3) can produce a variety of cross-section shape parts, such as curve type, multi-pass type, special type, etc.
Screw forging is generally used in the production of shaft parts, such as gear shaft, reducer shaft, valve shaft, etc.
3. Extrusion forging
Extrusion forging is a forging process using extrusion forging machine or shear forging machine. This process is a rod-shaped product that uses pressure to compress the billet into a small cross-section. Unlike hammerhead and spiral forging, extrusion forging is done from one side of the billet. The characteristics of extrusion forging are as follows:
(1) With high forging pressure, the performance of the billet is better improved;
(2) High process efficiency and fast production speed;
(3) Can produce long length parts, such as flexible shaft, large sealing cover, etc.
Extrusion forging is often used to produce complex fiber structure parts, such as steering shaft, gear shaft, etc.
4. Bend forging
Bending forging is a forging process that uses a bending machine. This process is forged by bending the billet, which has the following characteristics:
(1) Low forging cost;
(2) High production efficiency, can produce large quantities of products;
(3) The bending radius of the billet is small, so the bending forging can reduce the stress of the billet.
Bending forging is often used to produce parts with complex bending shapes such as threads, eye rods, connecting pipes and elbows.
5. Precision forging
Precision forging is to obtain parts with high precision and low sand grain through forging process. The process is flexible, controllable and has the following characteristics:
(1) the forging cost is slightly higher;
(2) High precision and good detail handling;
(3) Low production efficiency and high difficulty.
Precision forging is used to produce high precision, complex parts, such as drive shaft, advanced gear, etc.
6. Special forging
Special forging refers to some new techniques which are different from traditional forging. For example, continuous casting forging, rotary forging and so on, these processes have the characteristics of high efficiency, high quality and low cost. Special forging is used to produce mass batch parts, such as car bodies, frames, etc.
Four, the detection characteristics of automobile forgings
The detection requirement of automobile forgings is high, so it must be tested comprehensively to ensure its quality and reliability. The inspection of automobile forgings includes: appearance inspection, size inspection, blank inspection, heat treatment inspection, nondestructive testing, material analysis, etc. Among them, nondestructive testing is one of the important inspection methods of automobile forgings, mainly used to detect the cracks, defects and other defects of automobile forgings.
V. Conclusion
Automobile forging has strong adaptability and flexibility.